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Veluri S, Sowinski P, Svyntkivska M, Bartczak Z, Makowski T, Piorkowska E. Structure and Mechanical Properties of iPP-Based Nanocomposites Crystallized under High Pressure. Nanomaterials (Basel) 2024; 14:629. [PMID: 38607163 PMCID: PMC11013707 DOI: 10.3390/nano14070629] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2024] [Revised: 03/26/2024] [Accepted: 03/26/2024] [Indexed: 04/13/2024]
Abstract
The unique nonparallel chain arrangement in the orthorhombic γ-form lamellae of isotactic polypropylene (iPP) results in the enhancement of the mechanical properties of γ-iPP. Our study aimed at the investigation of the mechanical properties of γ-iPP nanocomposites with 1-5 wt.% multiwall carbon nanotubes (MWCNT) and 5 wt.% organo-modified montmorillonite prepared by melt-mixing and high-pressure crystallization. Neat iPP and the nanocomposites were crystallized under high pressures of 200 MPa and 300 MPa, and for comparison under 1.4 MPa, in a custom-built high-pressure cell. The structure of the materials was studied using WAXS, SAXS, DSC, and SEM, whereas their mechanical properties were tested in plane-strain compression. Under a small pressure of 1.4 MPa, polymer matrix in all materials crystallized predominantly in the α-form, the most common monoclinic form of iPP, whereas under high pressure it crystallized in the γ-form. This caused a significant increase in the elastic modulus, yield stress, and stress at break. Moreover, due to the presence of MWCNT, these parameters of the nanocomposites exceeded those of the neat polymer. As a result, a 60-70% increase in the elastic modulus, yield stress, and stress at break was achieved by filling of iPP with MWCNT and high-pressure crystallization.
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Affiliation(s)
| | | | | | | | | | - Ewa Piorkowska
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza 112, 90 363 Lodz, Poland; (S.V.); (P.S.); (M.S.); (Z.B.); (T.M.)
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2
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Svyntkivska M, Makowski T, Pawlowska R, Kregiel D, de Boer EL, Piorkowska E. Cytotoxicity studies and antibacterial modification of poly(ethylene 2,5-furandicarboxylate) nonwoven. Colloids Surf B Biointerfaces 2024; 233:113609. [PMID: 37925865 DOI: 10.1016/j.colsurfb.2023.113609] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Revised: 10/12/2023] [Accepted: 10/18/2023] [Indexed: 11/07/2023]
Abstract
Novel poly(ethylene 2,5-furandicarboxylate) PEF nonwovens were produced by solution electrospinning and further modification. To improve the wettability of the hydrophobic nonwovens with water, they were treated with sodium hydroxide. Cytotoxicity tests carried out with human keratinocytes confirmed that the nonwovens did not have a toxic effect on healthy cells. The hydrophilicity of the sodium hydroxide treated nonwoven favored the adherence of the cells and their growth. In turn, the two-step modification of the nonwovens by reactions with (3-mercaptopropyl)methyldimethoxysilane and silver nitrate permitted to deposit silver particles on the fiber surfaces. The bacteria growth inhibition zones around the tested specimens were observed evidencing their antibacterial activity against Escherichia coli and Staphylococcus aureus.
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Affiliation(s)
- Mariia Svyntkivska
- Centre of Molecular and Macromolecular Studies Polish Academy of Sciences, Sienkiewicza 112, 90-363 Lodz, Poland.
| | - Tomasz Makowski
- Centre of Molecular and Macromolecular Studies Polish Academy of Sciences, Sienkiewicza 112, 90-363 Lodz, Poland.
| | - Roza Pawlowska
- Centre of Molecular and Macromolecular Studies Polish Academy of Sciences, Sienkiewicza 112, 90-363 Lodz, Poland
| | - Dorota Kregiel
- Department of Environmental Biotechnology, Faculty of Biotechnology and Food Sciences, Lodz University of Technology, Wolczanska 171/173, 90-924 Lodz, Poland
| | - Ele L de Boer
- Avantium Renewable Polymers BV, Zekeringstraat 29, 1014 BV Amsterdam, the Netherlands
| | - Ewa Piorkowska
- Centre of Molecular and Macromolecular Studies Polish Academy of Sciences, Sienkiewicza 112, 90-363 Lodz, Poland
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Svyntkivska M, Makowski T, Kregiel D, Piorkowska E. Electrical Conductivity and Antibacterial Activity of Woven Fabrics through Quercetin-Assisted Thermal Reduction of a Graphene Oxide Coating. Materials (Basel) 2023; 16:7184. [PMID: 38005113 PMCID: PMC10672773 DOI: 10.3390/ma16227184] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Revised: 11/03/2023] [Accepted: 11/06/2023] [Indexed: 11/26/2023]
Abstract
Cotton and poly(ethylene terephthalate) (PET) woven fabrics were coated with graphene oxide (GO) using a padding method and the GO deposited on the fiber surfaces was thermally reduced to impart electrical conductivity to the fabrics. To assist the thermal reduction of GO, quercetin (Q)-a natural flavonoid-was used. To this end, before the reduction, the GO-padded fabrics were immersed in Q solutions in ethanol with different Q concentrations. Q enhanced the thermal reduction of GO. Depending on the Q concentration in the solutions, electrical surface resistivities of the cotton fabric of 750 kΩ/sq to 3.3 MΩ/sq and of the PET fabric of 240 kΩ/sq to 730 kΩ/sq were achieved. The cotton and PET fabrics also became hydrophobic, with water contact angles of 163° and 147°, respectively. In addition to the electrical conductivity, the presence of Q resulted in antibacterial activity of the fabrics against Escherichia coli and Staphylococcus aureus.
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Affiliation(s)
- Mariia Svyntkivska
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza 112, 90-363 Lodz, Poland;
| | - Tomasz Makowski
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza 112, 90-363 Lodz, Poland;
| | - Dorota Kregiel
- Department of Environmental Biotechnology, Faculty of Biotechnology and Food Sciences, Lodz University of Technology, Wolczanska 171/173, 90-924 Lodz, Poland;
| | - Ewa Piorkowska
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza 112, 90-363 Lodz, Poland;
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4
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Svyntkivska M, Makowski T, Shkyliuk I, Piorkowska E. Electrically conductive crystalline polylactide nonwovens obtained by electrospinning and modification with multiwall carbon nanotubes. Int J Biol Macromol 2023; 242:124730. [PMID: 37148928 DOI: 10.1016/j.ijbiomac.2023.124730] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Revised: 04/28/2023] [Accepted: 04/30/2023] [Indexed: 05/08/2023]
Abstract
Polylactide nonwovens were electrospun from solutions and then crystallized, one in the α-form, and another, S-PLA made of poly(l-lactide) and poly(d-lactide) 1:1 blend, in scPLA crystals with high melting temperature, close to 220 °C. To make the nonwovens electrically conductive, they were coated with multiwall carbon nanotubes (MWCNT) by padding with an aqueous dispersion of MWCNT or dip-coating in this dispersion. The electrical conductivity evidenced the formation of the electrically conductive MWCNT network on the fiber surfaces. Depending on the coating method, the surface resistivity (Rs) of S-PLA nonwoven of 1.0 kΩ/sq. and 0.09 kΩ/sq. was reached. To study the effect of surface roughness, before the modification the nonwovens were etched with sodium hydroxide, which additionally made them hydrophilic. The effect of etching depended on the coating method and led to an increase or decrease of Rs, in the case of padding or dip-coating, respectively. All MWCNT-modified nonwovens, unetched and etched, were hydrophobic with water contact angles of 138-144°. Scanning electron microscopy corroborated the presence of MWCNT on the fiber surfaces. The impedance spectroscopy confirmed the dominant role of the network of MWCNT direct contacts on the electrical properties of MWCNT-modified nonwovens in a broad frequency range.
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Affiliation(s)
- Mariia Svyntkivska
- Centre of Molecular and Macromolecular Studies Polish Academy of Sciences, Sienkiewicza 112, 90-363 Lodz, Poland
| | - Tomasz Makowski
- Centre of Molecular and Macromolecular Studies Polish Academy of Sciences, Sienkiewicza 112, 90-363 Lodz, Poland.
| | - Inna Shkyliuk
- Centre of Molecular and Macromolecular Studies Polish Academy of Sciences, Sienkiewicza 112, 90-363 Lodz, Poland; The Bio-Med-Chem Doctoral School of the University of Lodz and Lodz Institutes of the Polish Academy of Sciences, Banacha 12/16, Lodz 90-237, Poland
| | - Ewa Piorkowska
- Centre of Molecular and Macromolecular Studies Polish Academy of Sciences, Sienkiewicza 112, 90-363 Lodz, Poland
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Bujnicki B, Sowinski P, Makowski T, Krasowska D, Pokora-Sobczak P, Shkyliuk I, Drabowicz J, Piorkowska E. Microbiologically Pure Cotton Fabrics Treated with Tetrabutylammonium OXONE as Mild Disinfection Agent. Materials (Basel) 2022; 15:7749. [PMID: 36363341 PMCID: PMC9654703 DOI: 10.3390/ma15217749] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Revised: 10/17/2022] [Accepted: 10/26/2022] [Indexed: 06/16/2023]
Abstract
The microbiological purity of textiles plays a pivotal role in the use of textiles, especially in hospitals and other medical facilities. Microbiological purity of cotton fabric was achieved by a new disinfection method using tetrabutyloammonium OXONE (TBA-OXONE) before washing. As a result of the disinfection, the cotton fabric became microbiologically pure, despite the markedly decreased washing time with respect to the widely used standard procedure. Shortening of the washing time allowed for significant energy savings. In addition, the effect of the number of disinfection and washing cycles on the tensile properties and tearing force of the fabric was examined. After 120 disinfection and washing cycles the mechanical properties of cotton fabric were only slightly worsened.
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Affiliation(s)
- Bogdan Bujnicki
- Centre of Molecular and Macromolecular Studies Polish Academy of Sciences, Sienkiewicza 112, 90-363 Lodz, Poland
| | - Przemyslaw Sowinski
- Centre of Molecular and Macromolecular Studies Polish Academy of Sciences, Sienkiewicza 112, 90-363 Lodz, Poland
| | - Tomasz Makowski
- Centre of Molecular and Macromolecular Studies Polish Academy of Sciences, Sienkiewicza 112, 90-363 Lodz, Poland
| | - Dorota Krasowska
- Centre of Molecular and Macromolecular Studies Polish Academy of Sciences, Sienkiewicza 112, 90-363 Lodz, Poland
| | - Patrycja Pokora-Sobczak
- Centre of Molecular and Macromolecular Studies Polish Academy of Sciences, Sienkiewicza 112, 90-363 Lodz, Poland
| | - Inna Shkyliuk
- Centre of Molecular and Macromolecular Studies Polish Academy of Sciences, Sienkiewicza 112, 90-363 Lodz, Poland
- The Bio-Med-Chem Doctoral School of the University of Lodz and Lodz Institutes of the Polish Academy of Sciences, University of Lodz, Banacha 12/16, 90-237 Lodz, Poland
| | - Józef Drabowicz
- Centre of Molecular and Macromolecular Studies Polish Academy of Sciences, Sienkiewicza 112, 90-363 Lodz, Poland
- Institute of Chemistry, Jan Dlugosz University in Czestochowa, Armii Krajowej 13/15, 42-200 Czestochowa, Poland
| | - Ewa Piorkowska
- Centre of Molecular and Macromolecular Studies Polish Academy of Sciences, Sienkiewicza 112, 90-363 Lodz, Poland
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6
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Hosseinnezhad R, Vozniak I, Romano D, Rastogi S, Regnier G, Piorkowska E, Galeski A. Formation of UHMWPE Nanofibers during Solid-State Deformation. Nanomaterials (Basel) 2022; 12:nano12213825. [PMID: 36364602 PMCID: PMC9654675 DOI: 10.3390/nano12213825] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Revised: 10/18/2022] [Accepted: 10/24/2022] [Indexed: 05/12/2023]
Abstract
A network of nanofibers is formed in situ through solid-state deformation of disentangled ultra-high molecular weight polyethylene (dis-UHMWPE) during compounding with a polyolefin elastomer below the melting temperature of dis-UHMWPE crystals. Dis-UHMWPE was prepared in the form of powder particles larger than 50 μm by polymerization at low temperatures, which favored the crystallization and prevention of macromolecules from entangling. Shearing the blend for different durations and at different temperatures affects the extent to which the grains of dis-UHMWPE powder deform into nanofibers. Disentangled powder particles could deform into a network of nanofibers with diameters between 110 and 340 nm. The nanocomposite can be further sheared for a longer time to decrease the diameter of dis-UHMWPE nanofibers below 40 nm, being still composed of ≈70 wt.% of crystalline and ≈30 wt.% of amorphous components. Subsequently, these thinner fibers begin to melt and fragment because they are thinner and also because the amorphous defects locally decrease the nanofibers' melting temperature, which results in their fragmentation and partial loss of nanofibers. These phenomena limit the thickness of dis-UHMWPE nanofibers, and this explains why prolonged or more intense shearing does not lead to thinner nanofibers of dis-UHMWPE when compounded in a polymeric matrix.
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Affiliation(s)
- Ramin Hosseinnezhad
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, 90363 Lodz, Poland
| | - Iurii Vozniak
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, 90363 Lodz, Poland
| | - Dario Romano
- Faculty of Physical Sciences and Engineering, Division of Chemical Sciences, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Sanjay Rastogi
- Faculty of Physical Sciences and Engineering, Division of Chemical Sciences, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Gilles Regnier
- Procédés en Ingénierie Mécanique et Matériaux Laboratory, PIMM, Arts et Métiers, CNRS, CNAM, HESAM Université, 75013 Paris, France
| | - Ewa Piorkowska
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, 90363 Lodz, Poland
- Correspondence: (E.P.); (A.G.); Tel.: +48-42-6803-250 (A.G.)
| | - Andrzej Galeski
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, 90363 Lodz, Poland
- Correspondence: (E.P.); (A.G.); Tel.: +48-42-6803-250 (A.G.)
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7
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Makowski T, Svyntkivska M, Piorkowska E, Mizerska U, Fortuniak W, Kowalczyk D, Brzezinski S, Kregiel D. Antibacterial Electroconductive Composite Coating of Cotton Fabric. Materials (Basel) 2022; 15:ma15031072. [PMID: 35161018 PMCID: PMC8837966 DOI: 10.3390/ma15031072] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Revised: 01/17/2022] [Accepted: 01/20/2022] [Indexed: 01/08/2023]
Abstract
Graphene oxide (GO) was deposited on a cotton fabric and then thermally reduced to reduced graphene oxide (rGO) with the assistance of L-ascorbic acid. The GO reduction imparted electrical conductivity to the fabric and allowed for electrochemical deposition of Ag° particles using cyclic voltammetry. Only the Ag°/rGO composite coating imparted antibacterial properties to the fabric against Escherichia coli and Staphylococcus aureus. Ag°/rGO-modified fibers were free of bacterial film, and bacterial growth inhibition zones around the material specimens were found. Moreover, Ag°/rGO-modified fabric became superhydrophobic with WCA of 161°.
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Affiliation(s)
- Tomasz Makowski
- Centre of Molecular and Macromolecular Studies Polish Academy of Sciences, Sienkiewicza 112, 90-363 Lodz, Poland; (M.S.); (U.M.); (W.F.)
- Correspondence: (T.M.); (E.P.); Tel.: +48-42-6803-228 (T.M.)
| | - Mariia Svyntkivska
- Centre of Molecular and Macromolecular Studies Polish Academy of Sciences, Sienkiewicza 112, 90-363 Lodz, Poland; (M.S.); (U.M.); (W.F.)
| | - Ewa Piorkowska
- Centre of Molecular and Macromolecular Studies Polish Academy of Sciences, Sienkiewicza 112, 90-363 Lodz, Poland; (M.S.); (U.M.); (W.F.)
- Correspondence: (T.M.); (E.P.); Tel.: +48-42-6803-228 (T.M.)
| | - Urszula Mizerska
- Centre of Molecular and Macromolecular Studies Polish Academy of Sciences, Sienkiewicza 112, 90-363 Lodz, Poland; (M.S.); (U.M.); (W.F.)
| | - Witold Fortuniak
- Centre of Molecular and Macromolecular Studies Polish Academy of Sciences, Sienkiewicza 112, 90-363 Lodz, Poland; (M.S.); (U.M.); (W.F.)
| | - Dorota Kowalczyk
- Lukasiewicz Research Network, Textile Research Institute, Brzezinska 5/15, 92-103 Lodz, Poland; (D.K.); (S.B.)
| | - Stefan Brzezinski
- Lukasiewicz Research Network, Textile Research Institute, Brzezinska 5/15, 92-103 Lodz, Poland; (D.K.); (S.B.)
| | - Dorota Kregiel
- Department of Environmental Biotechnology, Faculty of Biotechnology and Food Sciences, Lodz University of Technology, Wolczanska 171/173, 90-924 Lodz, Poland;
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8
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Freymond C, Guinault A, Gervais M, Pluta M, Makowski T, Piorkowska E, Sollogoub C. Crystallization behavior and morphological features of ethylene-vinyl alcohol 44 copolymer. EXPRESS POLYM LETT 2022. [DOI: 10.3144/expresspolymlett.2022.26] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Bojda J, Piorkowska E, Lapienis G, Michalski A. Shear-Induced Crystallization of Star and Linear Poly(L-lactide)s. Molecules 2021; 26:6601. [PMID: 34771011 PMCID: PMC8588257 DOI: 10.3390/molecules26216601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Revised: 10/19/2021] [Accepted: 10/22/2021] [Indexed: 11/16/2022] Open
Abstract
The influence of macromolecular architecture on shear-induced crystallization of poly(L-lactide) (PLLA) was studied. To this aim, three star PLLAs, 6-arm with Mw of 120 and 245 kg/mol, 4-arm with Mw of 123 kg/mol, and three linear PLLAs with Mw of 121, 240 and 339 kg/mol, were synthesized and examined. The PLLAs were sheared at 170 and 150 °C, at 5/s, 10/s and 20/s for 20 s, 10 s and 5 s, respectively, and then cooled at 10 or 30 °C/min. Shear-induced crystallization during cooling was followed by a light depolarization method, whereas the crystallized specimens were examined by DSC, 2D-WAXS, 2D-SAXS and SEM. The effect of shear depended on the shearing conditions, cooling rate and polymer molar mass but it was also affected by the macromolecular architecture. The shear-induced crystallization of linear PLLA with Mw of 240 kg/mol was more intense than that of the 6-arm polymer with similar Mw, most possibly due to its higher Mz. However, the influence of shear on the crystallization of the star polymers with Mw close to 120 kg/mol was stronger than on that of their linear analog. This was reflected in higher crystallization temperature, as well as crystallinity achieved during cooling.
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Affiliation(s)
- Joanna Bojda
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza 112, 90-363 Lodz, Poland; (E.P.); (G.L.); (A.M.)
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10
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Mizerska U, Fortuniak W, Makowski T, Svyntkivska M, Piorkowska E, Kowalczyk D, Brzezinski S, Kregiel D. Antibacterial electroconductive
rGO
modified cotton fabric. POLYM ADVAN TECHNOL 2021. [DOI: 10.1002/pat.5430] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Urszula Mizerska
- Centre of Molecular and Macromolecular Studies Polish Academy of Sciences Sienkiewicza Lodz Poland
| | - Witold Fortuniak
- Centre of Molecular and Macromolecular Studies Polish Academy of Sciences Sienkiewicza Lodz Poland
| | - Tomasz Makowski
- Centre of Molecular and Macromolecular Studies Polish Academy of Sciences Sienkiewicza Lodz Poland
| | - Mariia Svyntkivska
- Centre of Molecular and Macromolecular Studies Polish Academy of Sciences Sienkiewicza Lodz Poland
| | - Ewa Piorkowska
- Centre of Molecular and Macromolecular Studies Polish Academy of Sciences Sienkiewicza Lodz Poland
| | - Dorota Kowalczyk
- Lukasiewicz Research Network Textile Research Institute Lodz Poland
| | | | - Dorota Kregiel
- Department of Environmental Biotechnology Lodz University of Technology Lodz Poland
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Kowalewska A, Herc AS, Bojda J, Nowacka M, Svyntkivska M, Piorkowska E, Kaczorowski W, Szymański W. Phase Structure and Properties of Ternary Polylactide/Poly(methyl methacrylate)/Polysilsesquioxane Blends. Polymers (Basel) 2021; 13:1033. [PMID: 33810345 PMCID: PMC8036706 DOI: 10.3390/polym13071033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Revised: 03/15/2021] [Accepted: 03/19/2021] [Indexed: 11/17/2022] Open
Abstract
Ternary blends of polylactide (PLA, 90 wt.%) and poly(methyl methacrylate) (PMMA, 10 wt.%) with functionalized polysilsesquioxanes (LPSQ-R) were obtained by solution blending. R groups in LPSQ containing hydroxyethyl (LPSQ-OH), methylglycolic (LPSQ-COOMe) and pentafluorophenyl (LPSQ-F5) moieties of different chemical properties were designed to modify PLA blends with PMMA. The effect of the type of LPSQ-R and their content, 1-3 wt.%, on the structure of the blends was studied with scanning electron microscopy (SEM) combined with energy dispersive spectroscopy (SEM-EDS), dynamic mechanical thermal analysis (DMTA) and Raman spectroscopy. Differential scanning calorimetry (DSC) and tensile tests also showed various effects of LPSQ-R on the thermal and mechanical properties of the blends. Depth-sensing indentation was used to resolve spatially the micro- and nano-scale mechanical properties (hardness and elastic behaviour) of the blends. The results showed clearly that LPSQ-R modulate the structure and properties of the blends.
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Affiliation(s)
- Anna Kowalewska
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza 112, 90-363 Lodz, Poland
| | - Agata S Herc
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza 112, 90-363 Lodz, Poland
| | - Joanna Bojda
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza 112, 90-363 Lodz, Poland
| | - Maria Nowacka
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza 112, 90-363 Lodz, Poland
| | - Mariia Svyntkivska
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza 112, 90-363 Lodz, Poland
| | - Ewa Piorkowska
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza 112, 90-363 Lodz, Poland
| | - Witold Kaczorowski
- Institute of Materials Science and Engineering, Lodz University of Technology, Stefanowskiego 1/15, 90-924 Lodz, Poland
| | - Witold Szymański
- Institute of Materials Science and Engineering, Lodz University of Technology, Stefanowskiego 1/15, 90-924 Lodz, Poland
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12
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Svyntkivska M, Makowski T, Piorkowska E, Brzezinski M, Herc A, Kowalewska A. Modification of Polylactide Nonwovens with Carbon Nanotubes and Ladder Poly(silsesquioxane). Molecules 2021; 26:1353. [PMID: 33802604 PMCID: PMC7961909 DOI: 10.3390/molecules26051353] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 02/21/2021] [Accepted: 02/21/2021] [Indexed: 11/17/2022] Open
Abstract
Electrospun nonwovens of poly(L-lactide) (PLLA) modified with multiwall carbon nanotubes (MWCNT) and linear ladder-like poly(silsesquioxane) with methoxycarbonyl side groups (LPSQ-COOMe) were obtained. MWCNT and LPSQ-COOMe were added to the polymer solution before the electrospinning. In addition, nonwovens of PLLA grafted to modified MWCNT were electrospun. All modified nonwovens exhibited higher tensile strength than the neat PLA nonwoven. The addition of 10 wt.% of LPSQ-COOMe and 0.1 wt.% of MWCNT to PLLA increased the tensile strength of the nonwovens 2.4 times, improving also the elongation at the maximum stress.
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Affiliation(s)
| | - Tomasz Makowski
- Centre of Molecular and Macromolecular Studies Polish Academy of Sciences, Sienkiewicza 112, 90-363 Lodz, Poland; (M.S.); (E.P.); (M.B.); (A.H.); (A.K.)
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13
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Sowinski P, Piorkowska E, Boyer SAE, Haudin JM. High-Pressure Crystallization of iPP Nucleated with 1,3:2,4-bis(3,4-dimethylbenzylidene)sorbitol. Polymers (Basel) 2021; 13:polym13010145. [PMID: 33401398 PMCID: PMC7795768 DOI: 10.3390/polym13010145] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Revised: 12/23/2020] [Accepted: 12/23/2020] [Indexed: 11/16/2022] Open
Abstract
1,3:2,4-bis(3,4-dimethylbenzylidene)sorbitol (DMDBS) is highly effective in nucleation of the α- form of isotactic polypropylene (iPP). However, its role in high-pressure crystallization of iPP, facilitating the formation of the γ- polymorph, has not been explored. The present paper focuses on the influence of DMDBS on nucleation of high-pressure crystallization of iPP. iPP with 0.2–1.0 wt.% of the DMDBS was crystallized under elevated pressure, up to 300 MPa, in various thermal conditions, and then analyzed by PLM, WAXD, SEM, and DSC. During cooling, crystallization temperatures (Tc) were determined. It was found that under high-pressure DMDBS nucleated crystallization of iPP in the orthorhombic γ- form. As a consequence, Tc and the γ- form content increased for the nucleated iPP, while the size of polycrystalline aggregates decreased, although the effects depended on DMDBS content. The significant increase of Tc and the decrease of grain size under high pressure of 200–300 MPa required higher content of DMDBS than the nucleation of the α-form under lower pressure, possibly due to the effect of pressure on crystallization of DMDBS itself, which is a prerequisite for its nucleating activity.
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Affiliation(s)
- Przemyslaw Sowinski
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza 112, 90 363 Lodz, Poland;
- Correspondence: ; Tel.: +48-426803316
| | - Ewa Piorkowska
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza 112, 90 363 Lodz, Poland;
| | - Severine A. E. Boyer
- Centre for Material Forming, MINES ParisTech, PSL-Research University, UMR CNRS 7635, 1 Rue Claude Daunesse, 06904 Sophia Antipolis, France; (S.A.E.B.); (J.-M.H.)
| | - Jean-Marc Haudin
- Centre for Material Forming, MINES ParisTech, PSL-Research University, UMR CNRS 7635, 1 Rue Claude Daunesse, 06904 Sophia Antipolis, France; (S.A.E.B.); (J.-M.H.)
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14
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Bucknall C, Altstädt V, Auhl D, Buckley P, Dijkstra D, Galeski A, Gögelein C, Handge UA, He J, Liu CY, Michler G, Piorkowska E, Slouf M, Vittorias I, Wu JJ. Structure, processing and performance of ultra-high molecular weight polyethylene (IUPAC Technical Report). Part 3: deformation, wear and fracture. PURE APPL CHEM 2020. [DOI: 10.1515/pac-2019-0406] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
Three grades of polyethylene, with weight-average relative molar masses,
M
‾
W
${\bar{M}}_{\text{W}}$
, of approximately 0.6 × 106, 5 × 106, and 9 × 106, were supplied as compression mouldings by a leading manufacturer of ultra-high molecular weight polyethylene (UHMWPE). They were code-named PE06, PE5, and PE9, respectively. Specimens cut from these mouldings were subjected to a wide range of mechanical tests at 23 °C. In tensile tests, deformation was initially elastic and dominated by crystallinity, which was highest in PE06. Beyond the yield point, entanglement density became the dominant factor, and at 40 % strain, the rising stress–strain curves for PE5 and PE9 crossed the falling PE06 curve. Fracture occurred at strains above 150 %. Differences in stress–strain behaviour between PE5 and PE9 were relatively small. A similar pattern of behaviour was observed in wear tests; wear resistance showed a marked increase when
M
‾
W
${\bar{M}}_{\text{W}}$
was raised from 0.6 × 106 to 5 × 106, but there was no further increase when it was raised to 9 × 106. It is concluded that the unexpected similarity in behaviour between PE5 and PE9 was due to incomplete consolidation during moulding, which led to deficiencies in entanglement at grain boundaries; they were clearly visible on the surfaces of both tensile and wear specimens. Fatigue crack growth in 10 mm thick specimens was so severely affected by inadequate consolidation that it forms the basis for a separate report – Part 4 in this series.
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Affiliation(s)
- Clive Bucknall
- School of Aerospace, Transport & Manufacturing B 61 , Cranfield University , Bedford, MK43 0AL , UK
| | - Volker Altstädt
- Department of Polymer Engineering , Universität Bayreuth , Bayreuth , Germany
| | - Dietmar Auhl
- Fakultät III – Werkstoffwissenschaft Technische , Universität Berlin , Berlin, D-10623 , Germany
| | - Paul Buckley
- Department of Engineering Science , University of Oxford , Oxford, OX1 3PJ , UK
| | | | - Andrzej Galeski
- Centre for Molecular and Macromolecular Sciences , Polish Academy of Sciences , Lodz , Poland
| | | | - Ulrich A. Handge
- Institute of Polymer Research , Helmholtz-Zentrum Geesthacht , Max-Planck-Strasse 1 , 21502, Geesthacht , Germany
| | - Jiasong He
- Chinese Academy of Sciences, Laboratory of Polymer Science and Materials , Beijing , China, 100190
| | - Chen-Yang Liu
- Chinese Academy of Sciences, Laboratory of Polymer Science and Materials , Beijing , China, 100190
| | - Goerg Michler
- Martin-Luther-Universität , Halle-Wittenberg , Germany
| | - Ewa Piorkowska
- Centre for Molecular and Macromolecular Sciences , Polish Academy of Sciences , Lodz , Poland
| | - Miroslav Slouf
- Institute of Macromolecular Chemistry CAS , Prague , Czech Republic
| | - Iakovos Vittorias
- Omya International AG , Baslerstrasse 42 , CH-4665, Oftringen , Switzerland
| | - Jun Jie Wu
- Department of Engineering , Durham University , Stockton Road , Durham, DH1 3LE , UK
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15
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Bucknall C, Altstädt V, Auhl D, Buckley P, Dijkstra D, Galeski A, Gögelein C, Handge UA, He J, Liu CY, Michler G, Piorkowska E, Slouf M, Vittorias I, Wu JJ. Structure, processing and performance of ultra-high molecular weight polyethylene (IUPAC Technical Report). Part 2: crystallinity and supra molecular structure. PURE APPL CHEM 2020. [DOI: 10.1515/pac-2019-0403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
Test methods including OM, SEM, TEM, DSC, SAXS, WAXS, and IR were used to characterise supra-molecular structure in three batches of polyethylene (PE), which had weight-average relative molar masses
M
¯
w
${\overline{M}}_{\text{w}}$
of approximately 0.6 × 106, 5 × 106, and 9 × 106. They were applied to compression mouldings made by the polymer manufacturer. Electron microscopy showed that powders formed in the polymerization reactor consisted of irregularly shaped grains between 50 and 250 μm in diameter. Higher magnification revealed that each grain was an aggregate, composed of particles between 0.4 and 0.8 μm in diameter, which were connected by long, thin fibrils. In compression mouldings, lamellar thicknesses ranged from 7 to 23 nm. Crystallinity varied between 70 and 75 % in reactor powder, but was lower in compression mouldings. Melting peak temperatures ranged from 138 to 145 °C, depending on processing history. DMTA showed that the glass transition temperature θ
g was −120 °C for all three grades of polyethylene. IR spectroscopy found negligibly small levels of oxidation and thermal degradation in mouldings. Optical microscopy revealed the presence of visible fusion defects at grain boundaries. It is concluded that relatively weak defects can be characterized using optical microscopy, but there is a need for improved methods that can detect less obvious fusion defects.
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Affiliation(s)
- Clive Bucknall
- School of Aerospace, Transport & Manufacturing B 61 , Cranfield University , Bedford, MK43 0AL , UK
| | - Volker Altstädt
- Department of Polymer Engineering , Universität Bayreuth , Bayreuth , Germany
| | - Dietmar Auhl
- Fakultät III – Werkstoffwissenschaft Technische Universität Berlin , D-10623, Berlin , Germany
| | - Paul Buckley
- Department of Engineering Science , University of Oxford , OX1 3PJ, Oxford , UK
| | | | - Andrzej Galeski
- Centre for Molecular and Macromolecular Sciences , Polish Academy of Sciences , Lodz , Poland
| | | | - Ulrich A. Handge
- Institute of Polymer Research , Helmholtz-Zentrum Geesthacht , Max-Planck-Strasse 1 , 21502, Geesthacht , Germany
| | - Jiasong He
- Chinese Academy of Sciences , Laboratory of Polymer Science and Materials , Beijing, 100190 , China
| | - Chen-Yang Liu
- Chinese Academy of Sciences , Laboratory of Polymer Science and Materials , Beijing, 100190 , China
| | - Goerg Michler
- Martin-Luther-Universität Halle-Wittenberg , Germany
| | - Ewa Piorkowska
- Centre for Molecular and Macromolecular Sciences , Polish Academy of Sciences , Lodz , Poland
| | - Miroslav Slouf
- Institute of Macromolecular Chemistry CAS , Prague , Czech Republic
| | - Iakovos Vittorias
- Omya International AG , Baslerstrasse 42 , CH-4665, Oftringen , Switzerland
| | - Jun Jie Wu
- Department of Engineering , Durham University , Stockton Road , Durham, DH1 3LE , UK
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Bucknall C, Altstädt V, Auhl D, Buckley P, Dijkstra D, Galeski A, Gögelein C, Handge UA, He J, Liu CY, Michler G, Piorkowska E, Slouf M, Vittorias I, Wu JJ. Structure, processing and performance of ultra-high molecular weight polyethylene (IUPAC Technical Report). Part 4: sporadic fatigue crack propagation. PURE APPL CHEM 2020. [DOI: 10.1515/pac-2019-0408] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
Fatigue tests were carried out on compression mouldings supplied by a leading polymer manufacturer. They were made from three batches of ultra-high molecular weight polyethylene (UHMWPE) with weight-average relative molar masses,
M
¯
W
${\overline{M}}_{\mathrm{W}}$
, of about 0.6 × 106, 5 × 106 and 9 × 106. In 10 mm thick compact tension specimens, crack propagation was so erratic that it was impossible to follow standard procedure, where crack-tip stress intensity amplitude, ΔK, is raised incrementally, and the resulting crack propagation rate, da/dN, increases, following the Paris equation, where a is crack length and N is number of cycles. Instead, most of the tests were conducted at fixed high values of ΔK. Typically, da/dN then started at a high level, but decreased irregularly during the test. Micrographs of fracture surfaces showed that crack propagation was sporadic in these specimens. In one test, at ΔK = 2.3 MPa m0.5, there were crack-arrest marks at intervals Δa of about 2 μm, while the number of cycles between individual growth steps increased from 1 to more than 1000 and the fracture surface showed increasing evidence of plastic deformation. It is concluded that sporadic crack propagation was caused by energy-dissipating crazing, which was initiated close to the crack tip under plane strain conditions in mouldings that were not fully consolidated. By contrast, fatigue crack propagation in 4 mm thick specimens followed the Paris equation approximately. The results from all four reports on this project are reviewed, and the possibility of using fatigue testing as a quality assurance procedure for melt-processed UHMWPE is discussed.
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Affiliation(s)
- Clive Bucknall
- B 61 School of Aerospace, Transport & Manufacturing , Cranfield University , Bedford, MK43 0AL , UK
| | - Volker Altstädt
- Department of Polymer Engineering , Universität Bayreuth , Bayreuth , Germany
| | - Dietmar Auhl
- Fakultät III – Werkstoffwissenschaft Technische , Universität Berlin , D-10623, Berlin , Germany
| | - Paul Buckley
- Department of Engineering Science , University of Oxford , Oxford, OX1 3PJ , UK
| | | | - Andrzej Galeski
- Centre for Molecular and Macromolecular Sciences , Polish Academy of Sciences , Lodz , Poland
| | | | - Ulrich A. Handge
- Institute of Polymer Research , Helmholtz-Zentrum Geesthacht , Max-Planck-Strasse 1 , Geesthacht, 21502 , Germany
| | - Jiasong He
- Chinese Academy of Sciences , Laboratory of Polymer Science and Materials , Beijing , China
| | - Chen-Yang Liu
- Chinese Academy of Sciences , Laboratory of Polymer Science and Materials , Beijing , China
| | - Goerg Michler
- Martin-Luther-Universität Halle-Wittenberg , Halle-Wittenberg , Germany
| | - Ewa Piorkowska
- Centre for Molecular and Macromolecular Sciences , Polish Academy of Sciences , Lodz , Poland
| | - Miroslav Slouf
- Institute of Macromolecular Chemistry CAS , Prague , Czech Republic
| | - Iakovos Vittorias
- Omya International AG , Baslerstrasse 42 , CH-4665, Oftringen , Switzerland
| | - Jun Jie Wu
- Department of Engineering , Durham University , Stockton Road , Durham, DH1 3LE , UK
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17
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Bucknall C, Altstädt V, Auhl D, Buckley P, Dijkstra D, Galeski A, Gögelein C, Handge UA, He J, Liu CY, Michler G, Piorkowska E, Slouf M, Vittorias I, Wu JJ. Structure, processing and performance of ultra-high molecular weight polyethylene (IUPAC Technical Report). Part 1: characterizing molecular weight. PURE APPL CHEM 2020. [DOI: 10.1515/pac-2019-0405] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
The aim of this project was to study the efficacy of current methods of quality control and quality assurance for ultra-high molecular weight polyethylene (UHMWPE) products, and find improvements where possible. Intrinsic viscosity (IV) tests were performed on three grades of polyethylene with weight average relative molar masses
M
̅
$̅{M}$
w of about 6 × 105, 5.0 × 106 and 9.0 × 106. Results from three laboratories showed substantial scatter, probably because different methods were used to make and test solutions. Tensile tests were carried out to 600 % extension at 150 °C under both constant applied load and constant Hencky strain rate, on compression mouldings made by a leading manufacturer of ultra-high molecular weight polyethylene. They gave low values of
M
̅
$̅{M}$
w, suggesting incomplete entanglement at ‘grain boundaries’ between powder particles. Results from conventional melt-rheology tests are presented, and their relevance to quality control and assurance is discussed. Attempts to calculate molecular weights from these data met with limited success because of extended relaxation times. Suggestions are made for improving international standards for IV testing of UHMWPE, by investigating the various factors that can cause significant errors, and by introducing methods for checking the homogeneity (and hence validity) of the solutions tested. Part 2 addresses characterization of crystallinity and structure. Part 3 covers mechanical properties, and Part 4 focuses on the sporadic crack propagation behaviour exhibited by all three grades of UHMWPE in fatigue tests on 10 mm thick compact tension specimens.
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Affiliation(s)
- Clive Bucknall
- B 61 School of Aerospace, Transport & Manufacturing , Cranfield University , Bedford , MK43 0AL , UK
| | - Volker Altstädt
- Department of Polymer Engineering , Universität Bayreuth , Bayreuth , Germany
| | - Dietmar Auhl
- Fakultät III - Werkstoffwissenschaft Technische Universität Berlin , Berlin , D-10623 , Germany
| | - Paul Buckley
- Department of Engineering Science , University of Oxford , Oxford , OX1 3PJ , UK
| | | | - Andrzej Galeski
- Centre for Molecular and Macromolecular Sciences , Polish Academy of Sciences , Lodz , Poland
| | | | - Ulrich A. Handge
- Institute of Polymer Research , Helmholtz-Zentrum Geesthacht , Max-Planck-Strasse 1 , Geesthacht , 21502 , Germany
| | - Jiasong He
- Chinese Academy of Sciences , Laboratory of Polymer Science and Materials , Beijing , 100190 , China
| | - Chen-Yang Liu
- Chinese Academy of Sciences , Laboratory of Polymer Science and Materials , Beijing , 100190 , China
| | - Goerg Michler
- Martin-Luther-Universität Halle-Wittenberg , Halle , Germany
| | - Ewa Piorkowska
- Centre for Molecular and Macromolecular Sciences , Polish Academy of Sciences , Lodz , Poland
| | - Miroslav Slouf
- Institute of Macromolecular Chemistry CAS , Prague , Czech Republic
| | - Iakovos Vittorias
- Omya International AG , Baslerstrasse 42 , Oftringen , CH-4665 , Switzerland
| | - Jun Jie Wu
- Department of Engineering , Durham University , Stockton Road , Durham , DH1 3LE , UK
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18
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Kost B, Svyntkivska M, Brzeziński M, Makowski T, Piorkowska E, Rajkowska K, Kunicka-Styczyńska A, Biela T. PLA/β-CD-based fibres loaded with quercetin as potential antibacterial dressing materials. Colloids Surf B Biointerfaces 2020; 190:110949. [DOI: 10.1016/j.colsurfb.2020.110949] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Revised: 03/02/2020] [Accepted: 03/04/2020] [Indexed: 01/30/2023]
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19
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Pluta M, Bojda J, Makowski T, Piorkowska E, Murariu M, Bonnaud L, Dubois P. Significant modification of the surface morphology of polylactide (PLA) and PLA-halloysite nanocomposites in the presence of N,N’-ethylenebis(stearamide) upon thermal treatment. EXPRESS POLYM LETT 2020. [DOI: 10.3144/expresspolymlett.2020.94] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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20
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Sowinski P, Piorkowska E, Boyer SA, Haudin JM. Corrigendum to “On the structure and nucleation mechanism in nucleated isotactic polypropylene crystallized under high pressure” [Polymer 151 (2018) 179-186]. POLYMER 2018. [DOI: 10.1016/j.polymer.2018.08.053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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21
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Pietrzak L, Piorkowska E, Galeski A, Bojda J, Sowinski P. Modification of Syndiotactic Polypropylene with Nano-Calcium Carbonate and Halloysite. INT POLYM PROC 2018. [DOI: 10.3139/217.3521] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Abstract
Composites of syndiotactic polypropylene (sPP) with 5 to 17 vol.° of halloysite and 2.5 to 7.5 vol.° of stearic acid modified nano-calcium carbonate, having an average grain size of 80 nm, were prepared and examined. The effect of fillers on thermal properties of sPP was different; halloysite increased markedly peak crystallization temperature. The composites with the highest filler contents, 7.5 vol.° of calcium carbonate and 17 vol.° of halloysite, exhibited a solid-like behavior at 170 °C, with the storage modulus exceeding the loss modulus in the entire frequency range, that is 512 to 0.1 rad s−1. The composites with halloysite exhibited decreased Izod impact strength compared to neat sPP. On the contrary, 2.7 fold improvement of the impact strength was found for the composites with nano-calcium carbonate. Moreover, nano-calcium carbonate did not worsen the drawability of the materials during uniaxial drawing. It was found that debonding at calcium carbonate/sPP interface occurred both during the impact test and tensile drawing facilitating the plastic deformation of the polymer.
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Affiliation(s)
- L. Pietrzak
- Centre of Molecular and Macromolecular Studies , Polish Academy of Sciences, Lodz , Poland
| | - E. Piorkowska
- Centre of Molecular and Macromolecular Studies , Polish Academy of Sciences, Lodz , Poland
| | - A. Galeski
- Centre of Molecular and Macromolecular Studies , Polish Academy of Sciences, Lodz , Poland
| | - J. Bojda
- Centre of Molecular and Macromolecular Studies , Polish Academy of Sciences, Lodz , Poland
| | - P. Sowinski
- Centre of Molecular and Macromolecular Studies , Polish Academy of Sciences, Lodz , Poland
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Sowinski P, Piorkowska E, Boyer SA, Haudin JM. Nucleation of crystallization of isotactic polypropylene in the gamma form under high pressure in nonisothermal conditions. Eur Polym J 2016. [DOI: 10.1016/j.eurpolymj.2016.10.055] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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24
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Affiliation(s)
- Lukasz Pietrzak
- Centre of Molecular and Macromolecular Studies; Polish Academy of Sciences; Sienkiewicza 112 Lodz 90 363 Poland
| | - Przemyslaw Sowinski
- Centre of Molecular and Macromolecular Studies; Polish Academy of Sciences; Sienkiewicza 112 Lodz 90 363 Poland
| | - Joanna Bojda
- Centre of Molecular and Macromolecular Studies; Polish Academy of Sciences; Sienkiewicza 112 Lodz 90 363 Poland
| | - Ewa Piorkowska
- Centre of Molecular and Macromolecular Studies; Polish Academy of Sciences; Sienkiewicza 112 Lodz 90 363 Poland
| | - Andrzej Galeski
- Centre of Molecular and Macromolecular Studies; Polish Academy of Sciences; Sienkiewicza 112 Lodz 90 363 Poland
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Slouf M, Vacková T, Zhigunov A, Sikora A, Piorkowska E. Nucleation of Polypropylene Crystallization with Gold Nanoparticles. Part 2: Relation between Particle Morphology and Nucleation Activity. J MACROMOL SCI B 2016. [DOI: 10.1080/00222348.2016.1153402] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Wojtczak M, Dutkiewicz S, Pietrzak L, Galeski A, Piorkowska E. Nucleation and crystallization of random aliphatic-butylene terephtalate copolyester. Eur Polym J 2015. [DOI: 10.1016/j.eurpolymj.2015.08.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Zubrowska A, Masirek R, Piorkowska E, Pietrzak L. Structure, thermal and mechanical properties of polypropylene composites with nano- and micro-diamonds. POLIMERY-W 2015. [DOI: 10.14314/polimery.2015.331] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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29
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Kowalczyk M, Piorkowska E, Dutkiewicz S, Sowinski P. Toughening of polylactide by blending with a novel random aliphatic–aromatic copolyester. Eur Polym J 2014. [DOI: 10.1016/j.eurpolymj.2014.07.002] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Zubrowska A, Piorkowska E, Kowalewska A, Cichorek M. Novel blends of polylactide with ethylene glycol derivatives of POSS. Colloid Polym Sci 2014; 293:23-33. [PMID: 25598571 PMCID: PMC4287653 DOI: 10.1007/s00396-014-3344-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2014] [Revised: 06/12/2014] [Accepted: 07/15/2014] [Indexed: 10/24/2022]
Abstract
Polylactide (PLA), a main biodegradable and biobased candidate for the replacement of petrochemical polymers, is stiff and brittle at room conditions. It is therefore of high interest to formulate new PLA-based materials suitable for applications demanding flexibility and toughness. In this work, novel blends of PLA with polyhedral oligomeric silsesquioxanes (POSS) grafted with longer (P1) and shorter (P2) arms of ethylene glycol derivatives were prepared and studied. It was hypothesized that, owing to their architecture with the central POSS cage grafted with arms, miscibility and stability of the blends could be improved. Indeed, PLA/P1 blends were homogeneous despite P1 relatively high Mw of 9,500 g mol-1. The blend with 20 wt% of P1, having Tg at 16 °C, was transparent and flexible, elastomer-like material with excellent drawability. The blend remained homogeneous and retained its good drawability as well as flexibility during 6 months of aging at room temperature: a 2 % secant modulus of elasticity well below 100 MPa, a low yield stress below 2 MPa, and and a large strain at break of 8 (800 %). Contary to that, PLA/P2 blends were only partially miscible. Nevertheless, owing to the liquid state of the dispersed phase, the blend with 15 wt% of P2 was transparent and ductile, with Tg at 49 °C, a relatively high yield strength of 29 MPa, and a large strain at break of 2.3 (230 %). The toughening mechanism involved the initiation of crazes and facilitation of their propagation by the liquid inclusions via the local plasticization effect.
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Affiliation(s)
- Anna Zubrowska
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza 112, 90-363 Lodz, Poland
| | - Ewa Piorkowska
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza 112, 90-363 Lodz, Poland
| | - Anna Kowalewska
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza 112, 90-363 Lodz, Poland
| | - Michal Cichorek
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza 112, 90-363 Lodz, Poland
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Szkudlarek E, Piorkowska E, Boyer S, Haudin J, Gadzinowska K. Nonisothermal shear-induced crystallization of polypropylene-based composite materials with montmorillonite. Eur Polym J 2013. [DOI: 10.1016/j.eurpolymj.2013.04.029] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Zapala K, Piorkowska E, Hiltner A, Baer E. High-pressure crystallization of isotactic polypropylene droplets. Colloid Polym Sci 2012; 290:1599-1607. [PMID: 23087537 PMCID: PMC3472077 DOI: 10.1007/s00396-012-2686-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2012] [Revised: 05/11/2012] [Accepted: 05/11/2012] [Indexed: 11/23/2022]
Abstract
Dispersions of isotactic polypropylene (PP) particles in polystyrene (PS) were produced by interfacially driven breakup of nanolayers in multilayered systems that were fabricated by means of layer-multiplying coextrusion. The droplet size was controlled by the individual PP layer thickness ranging from 12 to 200 nm. In addition, PP was melt blended with PS to produce PP droplets larger than those formed by breakup of nanolayers. The dispersions of PP particles in the PS matrix were melted and annealed under high pressure of 200 MPa. Only the largest PP droplets, with average sizes of 170 μm, crystallized predominantly in the γ form. In the 42-μm droplets obtained by breakup of 200 nm layers, a minor content of the γ form was found whereas the smaller droplets obtained by breakup of the thinner nanolayers contained the α form and/or the mesophase. The results showed that the γ phase formed only in the droplets sufficiently large to contain the most active heterogeneities nucleating PP crystallization under atmospheric pressure. It is concluded that the presence of nucleating heterogeneities is necessary for crystallization of PP in the γ form under high pressure.
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Affiliation(s)
- Kinga Zapala
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza 112, 90 363 Lodz, Poland
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Kowalczyk M, Pluta M, Piorkowska E, Krasnikova N. Plasticization of polylactide with block copolymers of ethylene glycol and propylene glycol. J Appl Polym Sci 2012. [DOI: 10.1002/app.36563] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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Slouf M, Sikora A, Pavlova E, Vlkova H, Baldrian J, Base T, Piorkowska E. Nucleated crystallization of isotactic polypropylene in multilayered sandwich nanocomposites with gold particles. J Appl Polym Sci 2012. [DOI: 10.1002/app.36589] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Kowalczyk M, Piorkowska E. Mechanisms of plastic deformation in biodegradable polylactide/poly(1,4-cis-isoprene) blends. J Appl Polym Sci 2011. [DOI: 10.1002/app.35489] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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Masirek R, Piorkowska E. Nucleation of crystallization in isotactic polypropylene and polyoxymethylene with poly(tetrafluoroethylene) particles. Eur Polym J 2010. [DOI: 10.1016/j.eurpolymj.2010.04.021] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Pavlova E, Slouf M, Sandova H, Baldrian J, Sikora A, Lednicky F, Masirek R, Piorkowska E. Nucleation of Polypropylene with Gold Nanoparticles. Part 1: Introduction of Sandwich Method for Evaluation of Very Weak Nucleation Activity. J MACROMOL SCI B 2010. [DOI: 10.1080/00222340903546812] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- Ewa Pavlova
- a Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic , Heyrovsky Sq. 2 162 06, Prague 6, Czech Republic
| | - Miroslav Slouf
- a Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic , Heyrovsky Sq. 2 162 06, Prague 6, Czech Republic
| | - Hana Sandova
- a Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic , Heyrovsky Sq. 2 162 06, Prague 6, Czech Republic
| | - Josef Baldrian
- a Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic , Heyrovsky Sq. 2 162 06, Prague 6, Czech Republic
| | - Antonin Sikora
- a Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic , Heyrovsky Sq. 2 162 06, Prague 6, Czech Republic
| | - Frantisek Lednicky
- a Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic , Heyrovsky Sq. 2 162 06, Prague 6, Czech Republic
| | - Robert Masirek
- a Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic , Heyrovsky Sq. 2 162 06, Prague 6, Czech Republic
| | - Ewa Piorkowska
- b Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences , Sienkiewicza 112, 90 630, Lodz, Poland
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Masirek R, Szkudlarek E, Piorkowska E, Slouf M, Kratochvil J, Baldrian J. Nucleation of isotactic polypropylene crystallization by gold nanoparticles. ACTA ACUST UNITED AC 2010. [DOI: 10.1002/polb.21908] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Lezak E, Kulinski Z, Masirek R, Piorkowska E, Pracella M, Gadzinowska K. Mechanical and thermal properties of green polylactide composites with natural fillers. Macromol Biosci 2009; 8:1190-200. [PMID: 18698579 DOI: 10.1002/mabi.200800040] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Green composites of PLA with micropowders derived from agricultural by-products such as oat husks, cocoa shells, and apple solids that remain after pressing have been prepared by melt mixing. The thermal and mechanical properties of the composites, including the effect of matrix crystallization and plasticization with poly(propylene glycol), have been studied. All fillers nucleated PLA crystallization and decreased the cold-crystallization temperature. They also affected the mechanical properties of the compositions, increasing the modulus of elasticity but decreasing the elongation at break and tensile impact strength although with few exceptions. Plasticization of the PLA matrix improved the ductility of the composites.
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Affiliation(s)
- Emil Lezak
- Centre of Molecular and Macromolecular Studies, PAS, Lodz, Poland
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Affiliation(s)
- Robert Masirek
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, 90 363 Lodz, Poland, and Department of Macromolecular Science and Center for Applied Polymer Research, Case Western Reserve University, Cleveland, Ohio, 44106-7202
| | - Ewa Piorkowska
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, 90 363 Lodz, Poland, and Department of Macromolecular Science and Center for Applied Polymer Research, Case Western Reserve University, Cleveland, Ohio, 44106-7202
| | - Andrzej Galeski
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, 90 363 Lodz, Poland, and Department of Macromolecular Science and Center for Applied Polymer Research, Case Western Reserve University, Cleveland, Ohio, 44106-7202
| | - Anne Hiltner
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, 90 363 Lodz, Poland, and Department of Macromolecular Science and Center for Applied Polymer Research, Case Western Reserve University, Cleveland, Ohio, 44106-7202
| | - Eric Baer
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, 90 363 Lodz, Poland, and Department of Macromolecular Science and Center for Applied Polymer Research, Case Western Reserve University, Cleveland, Ohio, 44106-7202
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Affiliation(s)
- Ewa Piorkowska
- a Center of Molecular and Macromolecular Studies , Polish Academy of Sciences , Sienkiewicza, Poland
| | - Andrzej Galeski
- a Center of Molecular and Macromolecular Studies , Polish Academy of Sciences , Sienkiewicza, Poland
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Masirek R, Kulinski Z, Chionna D, Piorkowska E, Pracella M. Composites of poly(L-lactide) with hemp fibers: Morphology and thermal and mechanical properties. J Appl Polym Sci 2007. [DOI: 10.1002/app.26090] [Citation(s) in RCA: 168] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Masirek R, Piorkowska E, Galeski A, Mucha M. Influence of thermal history on the nonisothermal crystallization of poly(L-lactide). J Appl Polym Sci 2007. [DOI: 10.1002/app.26047] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Lotz B, Ruan J, Thierry A, Alfonso GC, Hiltner A, Baer E, Piorkowska E, Galeski A. A Structure of Copolymers of Propene and Hexene Isomorphous to Isotactic Poly(1-butene) Form I. Macromolecules 2006. [DOI: 10.1021/ma052314i] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- B. Lotz
- Institut Charles Sadron (CNRS-ULP), 6 rue Boussingault, 67083 Strasbourg, France, Department of Chemistry and Industrial Chemistry, University of Genova, Via Dodecaneso, 31, 16146 Genova, Italy, Department of Macromolecular Science and Center for Applied Polymer Research, Case Western University, Cleveland, Ohio 44106-7202, and Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienciewicza 112, 90363 Łodz, Poland
| | - J. Ruan
- Institut Charles Sadron (CNRS-ULP), 6 rue Boussingault, 67083 Strasbourg, France, Department of Chemistry and Industrial Chemistry, University of Genova, Via Dodecaneso, 31, 16146 Genova, Italy, Department of Macromolecular Science and Center for Applied Polymer Research, Case Western University, Cleveland, Ohio 44106-7202, and Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienciewicza 112, 90363 Łodz, Poland
| | - A. Thierry
- Institut Charles Sadron (CNRS-ULP), 6 rue Boussingault, 67083 Strasbourg, France, Department of Chemistry and Industrial Chemistry, University of Genova, Via Dodecaneso, 31, 16146 Genova, Italy, Department of Macromolecular Science and Center for Applied Polymer Research, Case Western University, Cleveland, Ohio 44106-7202, and Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienciewicza 112, 90363 Łodz, Poland
| | - G. C. Alfonso
- Institut Charles Sadron (CNRS-ULP), 6 rue Boussingault, 67083 Strasbourg, France, Department of Chemistry and Industrial Chemistry, University of Genova, Via Dodecaneso, 31, 16146 Genova, Italy, Department of Macromolecular Science and Center for Applied Polymer Research, Case Western University, Cleveland, Ohio 44106-7202, and Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienciewicza 112, 90363 Łodz, Poland
| | - A. Hiltner
- Institut Charles Sadron (CNRS-ULP), 6 rue Boussingault, 67083 Strasbourg, France, Department of Chemistry and Industrial Chemistry, University of Genova, Via Dodecaneso, 31, 16146 Genova, Italy, Department of Macromolecular Science and Center for Applied Polymer Research, Case Western University, Cleveland, Ohio 44106-7202, and Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienciewicza 112, 90363 Łodz, Poland
| | - E. Baer
- Institut Charles Sadron (CNRS-ULP), 6 rue Boussingault, 67083 Strasbourg, France, Department of Chemistry and Industrial Chemistry, University of Genova, Via Dodecaneso, 31, 16146 Genova, Italy, Department of Macromolecular Science and Center for Applied Polymer Research, Case Western University, Cleveland, Ohio 44106-7202, and Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienciewicza 112, 90363 Łodz, Poland
| | - E. Piorkowska
- Institut Charles Sadron (CNRS-ULP), 6 rue Boussingault, 67083 Strasbourg, France, Department of Chemistry and Industrial Chemistry, University of Genova, Via Dodecaneso, 31, 16146 Genova, Italy, Department of Macromolecular Science and Center for Applied Polymer Research, Case Western University, Cleveland, Ohio 44106-7202, and Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienciewicza 112, 90363 Łodz, Poland
| | - A. Galeski
- Institut Charles Sadron (CNRS-ULP), 6 rue Boussingault, 67083 Strasbourg, France, Department of Chemistry and Industrial Chemistry, University of Genova, Via Dodecaneso, 31, 16146 Genova, Italy, Department of Macromolecular Science and Center for Applied Polymer Research, Case Western University, Cleveland, Ohio 44106-7202, and Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienciewicza 112, 90363 Łodz, Poland
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Abstract
A new plasticizer for poly(L-lactide) (PLA)-poly(propylene glycol) (PPG) is proposed. The advantage of using PPG is that it does not crystallize, has low glass transition temperature, and is miscible with PLA. PLA was plasticized with PPGs with nominal Mw of 425 and 1000 g/mol. Poly(ethylene glycol) (PEG), long known as a plasticizer for PLA, with nominal Mw of 600 g/mol, was also used to plasticize PLA for comparison. The thermal and tensile properties of PLA and PLA with 5-12.5 wt % of the plasticizers were studied. In blends of PLA with PPGs the glass transition temperature was lower than that of neat PLA. Both PPGs enhanced the crystallizability of PLA albeit less than PEG. All of the plasticizers increased also the ability of PLA to plastic deformation which was reflected in a decrease of yield stress and in an increase of elongation at break. The effect was enhanced by the higher PPG content and also by lower molecular weight of PPG. A phase separation occurred only in the blend containing 12.5 wt % of PPG with higher molecular weight. The evidences of crazing were found in deformed samples of PLA with low plasticizer content, whereas the samples with higher content of plasticizers crystallized due to deformation.
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Affiliation(s)
- Z Kulinski
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, 90 363 Lodz, Poland
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Jin Y, Hiltner A, Baer E, Masirek R, Piorkowska E, Galeski A. Formation and transformation of smectic polypropylene nanodroplets. ACTA ACUST UNITED AC 2006. [DOI: 10.1002/polb.20839] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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