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Guadagno L, Naddeo C, Sorrentino A, Raimondo M. Thermo-Mechanical Performance of Epoxy Hybrid System Based on Carbon Nanotubes and Graphene Nanoparticles. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:2427. [PMID: 37686935 PMCID: PMC10489851 DOI: 10.3390/nano13172427] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2023] [Revised: 08/22/2023] [Accepted: 08/24/2023] [Indexed: 09/10/2023]
Abstract
This study focuses on epoxy hybrid systems prepared by incorporating multi-wall carbon nanotubes (MWCNTs) and graphene nanosheets (GNs) at two fixed filler amounts: below (0.1 wt%) and above (0.5 wt%), with varying MWCNT:GN mix ratios. The hybrid epoxy systems exhibited remarkable electrical performance, attributed to the π-π bond interactions between the multi-wall carbon nanotubes and the graphene layers dispersed in the epoxy resin matrix. The material's properties were characterized through dynamic mechanical and thermal analyses over a wide range of temperatures. In addition to excellent electrical properties, the formulated hybrid systems demonstrated high mechanical performance and thermal stability. Notably, the glass transition temperature of the samples reached 255 °C, and high storage modulus values at elevated temperatures were observed. The hybrid systems also displayed thermal stability up to 360 °C in air. By comparing the mechanical and electrical performance, the formulation can be optimized in terms of the electrical percolation threshold (EPT), electrical conductivity, thermostability, and mechanical parameters. This research provides valuable insights for designing advanced epoxy-based materials with multifunctional properties.
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Affiliation(s)
- Liberata Guadagno
- Department of Industrial Engineering, University of Salerno, Via Giovanni Paolo II, 132, 84084 Fisciano, Italy; (L.G.); (C.N.)
| | - Carlo Naddeo
- Department of Industrial Engineering, University of Salerno, Via Giovanni Paolo II, 132, 84084 Fisciano, Italy; (L.G.); (C.N.)
| | - Andrea Sorrentino
- Institute for Polymers, Composites, and Biomaterials (IPCB-CNR), Via Previati n. 1/E, 23900 Lecco, Italy;
| | - Marialuigia Raimondo
- Department of Industrial Engineering, University of Salerno, Via Giovanni Paolo II, 132, 84084 Fisciano, Italy; (L.G.); (C.N.)
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2
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Spinelli G, Guarini R, Kotsilkova R, Ivanov E, Romano V. Experimental, Theoretical and Numerical Studies on Thermal Properties of Lightweight 3D Printed Graphene-Based Discs with Designed Ad Hoc Air Cavities. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:1863. [PMID: 37368293 DOI: 10.3390/nano13121863] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Revised: 06/12/2023] [Accepted: 06/13/2023] [Indexed: 06/28/2023]
Abstract
The current state of the art on material science emphasizes recent research efforts aimed at designing novel materials characterized by low-density and advanced properties. The present article reports the experimental, theoretical and simulation results on the thermal behavior of 3D printed discs. Filaments of pure poly (lactic acid) PLA and filled with 6 wt% of graphene nanoplatelets (GNPs) are used as feedstocks. Experiments indicate that the introduction of graphene enhances the thermal properties of the resulting materials since the conductivity passes from the value of 0.167 [W/mK] for unfilled PLA to 0.335 [W/mK] for reinforced PLA, which corresponds to a significantly improvement of 101%. Exploiting the potential of 3D printing, different air cavities have been intentionally designed to develop new lightweight and more cost-effective materials without compromising their thermal performances. Furthermore, some cavities are equal in volume but different in the geometry; it is necessary to investigate how this last characteristic and its possible orientations affect the overall thermal behavior compared to that of an air-free specimen. The influence of air volume is also investigated. Experimental results are supported by theoretical analysis and simulation studies based on the finite element method. The results aim to be a valuable reference resource in the field of design and optimization of lightweight advanced materials.
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Affiliation(s)
- Giovanni Spinelli
- Faculty of Transport Sciences and Technologies, University of Study "Giustino Fortunato", Via Raffaele Delcogliano 12, 82100 Benevento, Italy
- Institute of Mechanics, Bulgarian Academy of Sciences, Acadamy. G. Bonchev Str., Block 4, 1113 Sofia, Bulgaria
| | - Rosella Guarini
- Institute of Mechanics, Bulgarian Academy of Sciences, Acadamy. G. Bonchev Str., Block 4, 1113 Sofia, Bulgaria
| | - Rumiana Kotsilkova
- Institute of Mechanics, Bulgarian Academy of Sciences, Acadamy. G. Bonchev Str., Block 4, 1113 Sofia, Bulgaria
| | - Evgeni Ivanov
- Institute of Mechanics, Bulgarian Academy of Sciences, Acadamy. G. Bonchev Str., Block 4, 1113 Sofia, Bulgaria
- Research and Development of Nanomaterials and Nanotechnologies (NanoTech Lab Ltd.), Acad. G. Bonchev Str., Block 4, 1113 Sofia, Bulgaria
| | - Vittorio Romano
- Department of Industrial Engineering, University of Salerno, Via Giovanni Paolo II, 84084 Fisciano, Italy
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Farcas C, Galao O, Vertuccio L, Guadagno L, Romero-Sánchez MD, Rodríguez-Pastor I, Garcés P. Ice-Prevention and De-Icing Capacity of Epoxy Resin Filled with Hybrid Carbon-Nanostructured Forms: Self-Heating by Joule Effect. NANOMATERIALS 2021; 11:nano11092427. [PMID: 34578741 PMCID: PMC8465919 DOI: 10.3390/nano11092427] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Revised: 09/10/2021] [Accepted: 09/13/2021] [Indexed: 11/16/2022]
Abstract
In this study, CNTs and graphite have been incorporated to provide electrical conductivity and self-heating capacity by Joule effect to an epoxy matrix. Additionally, both types of fillers, with different morphology, surface area and aspect ratio, were simultaneously incorporated (hybrid CNTs and graphite addition) into the same epoxy matrix to evaluate the effect of the self-heating capacity of carbon materials-based resins on de-icing and ice-prevention capacity. The self-heating capacity by Joule effect and the thermal conductivity of the differently filled epoxy resin were evaluated for heating applications at room temperature and at low temperatures for de-icing and ice-prevention applications. The results show that the higher aspect ratio of the CNTs determined the higher electrical conductivity of the epoxy resin compared to that of the epoxy resin filled with graphite, but the 2D morphology of graphite produced the higher thermal conductivity of the filled epoxy resin. The presence of graphite enhanced the thermal stability of the filled epoxy resin, helping avoid its deformation produced by the softening of the epoxy resin (the higher the thermal conductivity, the higher the heat dissipation), but did not contribute to the self-heating by Joule effect. On the other hand, the feasibility of electrically conductive epoxy resins for de-icing and ice-prevention applications by Joule effect was demonstrated.
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Affiliation(s)
- Catalina Farcas
- Civil Engineering Department, University of Alicante, Ctra. San Vicente s/n, 03690 San Vicente del Raspeig, Spain; (C.F.); (O.G.); (P.G.)
| | - Oscar Galao
- Civil Engineering Department, University of Alicante, Ctra. San Vicente s/n, 03690 San Vicente del Raspeig, Spain; (C.F.); (O.G.); (P.G.)
| | - Luigi Vertuccio
- Department of Industrial Engineering, University of Salerno, Via Giovanni Paolo II, 84084 Fisciano, Italy; (L.V.); (L.G.)
| | - Liberata Guadagno
- Department of Industrial Engineering, University of Salerno, Via Giovanni Paolo II, 84084 Fisciano, Italy; (L.V.); (L.G.)
| | - M. Dolores Romero-Sánchez
- Applynano Solutions, S.L. Parque Científico de Alicante, 03690 San Vicente del Raspeig, Spain;
- Correspondence:
| | | | - Pedro Garcés
- Civil Engineering Department, University of Alicante, Ctra. San Vicente s/n, 03690 San Vicente del Raspeig, Spain; (C.F.); (O.G.); (P.G.)
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4
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Spinelli G, Guarini R, Kotsilkova R, Ivanov E, Romano V. Experimental, Theoretical and Simulation Studies on the Thermal Behavior of PLA-Based Nanocomposites Reinforced with Different Carbonaceous Fillers. NANOMATERIALS 2021; 11:nano11061511. [PMID: 34200476 PMCID: PMC8226525 DOI: 10.3390/nano11061511] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Revised: 06/01/2021] [Accepted: 06/03/2021] [Indexed: 01/25/2023]
Abstract
Many research efforts have been directed towards enhancing the thermal properties of polymers, since they are classically regarded as thermal insulators. To this end, the present study focuses on the thermal investigation of poly(lactic acid) (PLA) filled with two types of carbon nanotubes (trade names: TNIMH4 and N7000), two type of graphene nanoplatelets (trade names: TNIGNP and TNGNP), or their appropriate combination. A significant increase in the thermal conductivity by 254% with respect to that of unfilled polymer was achieved in the best case by using 9 wt% TNIGNP, resulting from its favorable arrangement and the lower thermal boundary resistance between the two phases, matrix and filler. To theoretically assist the design of such advanced nanocomposites, Design of Experiments (DoE) and Response Surface Method (RSM) were employed, respectively, to obtain information on the conditioning effect of each filler loading on the thermal conductivity and to find an analytical relationship between them. The numerical results were compared with the experimental data in order to confirm the reliability of the prediction. Finally, a simulation study was carried out with Comsol Multiphysics® for a comparative study between two heat sinks based on pure PLA, and to determine the best thermally performing nanocomposite with a view towards potential use in heat transfer applications.
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Affiliation(s)
- Giovanni Spinelli
- Open Laboratory on Experimental Micro and Nano Mechanics (OLEM), Institute of Mechanics, Bulgarian Academy of Sciences, Acad. G. Bonchev Str. Block 4, 1113 Sofia, Bulgaria; (R.G.); (R.K.); (E.I.)
- Correspondence: ; Tel.: +359-2-979-6476
| | - Rosella Guarini
- Open Laboratory on Experimental Micro and Nano Mechanics (OLEM), Institute of Mechanics, Bulgarian Academy of Sciences, Acad. G. Bonchev Str. Block 4, 1113 Sofia, Bulgaria; (R.G.); (R.K.); (E.I.)
| | - Rumiana Kotsilkova
- Open Laboratory on Experimental Micro and Nano Mechanics (OLEM), Institute of Mechanics, Bulgarian Academy of Sciences, Acad. G. Bonchev Str. Block 4, 1113 Sofia, Bulgaria; (R.G.); (R.K.); (E.I.)
| | - Evgeni Ivanov
- Open Laboratory on Experimental Micro and Nano Mechanics (OLEM), Institute of Mechanics, Bulgarian Academy of Sciences, Acad. G. Bonchev Str. Block 4, 1113 Sofia, Bulgaria; (R.G.); (R.K.); (E.I.)
- Research and Development of Nanomaterials and Nanotechnologies (NanoTech Lab Ltd.), Acad. G. Bonchev Str. Block 4, 1113 Sofia, Bulgaria
| | - Vittorio Romano
- Department of Industrial Engineering, University of Salerno, Via Giovanni Paolo II, 132, 84084 Fisciano, Italy;
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Aryanfar A, Medlej S, Tarhini A, Tehrani B AR. Elliptic percolation model for predicting the electrical conductivity of graphene-polymer composites. SOFT MATTER 2021; 17:2081-2089. [PMID: 33439207 DOI: 10.1039/d0sm01950j] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Graphene-based polymers exhibit a conductive microstructure formed by aggregates in a matrix which drastically enhances their transmitting properties. We develop a new numerical framework for predicting the electrical conductivity based on continuum percolation theory in a two dimensional stochastically-generated medium. We analyze the role of the flake shape and its aspect ratio and consequently predict the onset of percolation based on the particle density and the domain scale. Simultaneously, we have performed experiments and have achieved very high electrical conductivity for such composites compared to other film fabrication techniques, which have verified the results of computing the homogenized electrical conductivity. As well, the proximity to and a comparison with other analytical models and other experimental techniques are presented. The numerical model can predict the composite transmitting conductivity in a larger range of particle geometry. Such quantification is exceedingly useful for effective utilization and optimization of graphene filler densities and their spatial distribution during manufacturing.
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Affiliation(s)
- Asghar Aryanfar
- American University of Beirut, Riad El-Solh 1107, Lebanon.
- Bahçesehir University, 4 Çırağan Cad, Besiktas, Istanbul 34353, Turkey
| | - Sajed Medlej
- American University of Beirut, Riad El-Solh 1107, Lebanon.
| | - Ali Tarhini
- American University of Beirut, Riad El-Solh 1107, Lebanon.
| | - Ali R Tehrani B
- American University of Beirut, Riad El-Solh 1107, Lebanon.
- Aalto University, Chemical Engineering, Espoo 02150, Finland
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Guadagno L, Foglia F, Pantani R, Romero-Sanchez MD, Calderón B, Vertuccio L. Low-Voltage Icing Protection Film for Automotive and Aeronautical Industries. NANOMATERIALS 2020; 10:nano10071343. [PMID: 32660161 PMCID: PMC7408020 DOI: 10.3390/nano10071343] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 06/22/2020] [Accepted: 07/07/2020] [Indexed: 11/16/2022]
Abstract
High-performance heater films are here proposed. They manifest great applicative potentiality in the de-icing technology of aircraft and motor vehicles. The films are suitable to be integrated into composite structures for the de/anti-icing function, which can be activated if the need arises. The heating is based on the joule effect of the current flowing through the electrically conductive films. Voltage and current parameters have been set based on the generators’ capacities on-board an aircraft and a car, as well as on the energy consumption during the operating conditions and the autonomy in the time. Green processes have been employed through all preparative steps of the films, which are composed of expanded graphite (60% wt/wt) and polyvinyl alcohol (PVA) (40% wt/wt). The results reveal a very significant influence of the aspect ratio of the filler on the heating and de-icing performance and suggest how to enhance the de-icing efficiency saving energy and adapting the current on-board aircraft/car generators for de-icing operations.
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Affiliation(s)
- Liberata Guadagno
- Department of Industrial Engineering, University of Salerno, Via Giovanni Paolo II, 132, 84084 Fisciano (SA), Italy; (F.F.); (R.P.)
- Correspondence: (L.G.); (L.V.)
| | - Fabiana Foglia
- Department of Industrial Engineering, University of Salerno, Via Giovanni Paolo II, 132, 84084 Fisciano (SA), Italy; (F.F.); (R.P.)
| | - Roberto Pantani
- Department of Industrial Engineering, University of Salerno, Via Giovanni Paolo II, 132, 84084 Fisciano (SA), Italy; (F.F.); (R.P.)
| | - Maria Dolores Romero-Sanchez
- Applynano Solutions S.L., Parque Científico de Alicante, Naves de Apoyo, 3, Zona Ampliación del Campus, 03005 Alicante, Spain; (M.D.R.-S.); (B.C.)
| | - Blanca Calderón
- Applynano Solutions S.L., Parque Científico de Alicante, Naves de Apoyo, 3, Zona Ampliación del Campus, 03005 Alicante, Spain; (M.D.R.-S.); (B.C.)
| | - Luigi Vertuccio
- Department of Industrial Engineering, University of Salerno, Via Giovanni Paolo II, 132, 84084 Fisciano (SA), Italy; (F.F.); (R.P.)
- Correspondence: (L.G.); (L.V.)
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7
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Nobile MR, Raimondo M, Naddeo C, Guadagno L. Rheological and Morphological Properties of Non-Covalently Functionalized Graphene-Based Structural Epoxy Resins with Intrinsic Electrical Conductivity and Thermal Stability. NANOMATERIALS 2020; 10:nano10071310. [PMID: 32635410 PMCID: PMC7408570 DOI: 10.3390/nano10071310] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Revised: 06/18/2020] [Accepted: 06/28/2020] [Indexed: 11/16/2022]
Abstract
In this paper, a non-covalent π–π interaction between graphene nanoparticles (G) and a pyrene-based molecule (py) has been successfully accomplished to give the functionalized nanofillers (G-py). The proposed modification has proven to be a winning solution aimed at safeguarding the graphene’s notable electronic properties, while promoting a more effective nanofiller dispersion attributable to a decrease in viscosity with consequent improvement of the rheological properties of the formulated nanocomposites filled with G-py. The electrical current maps of the G-py based epoxy composites, loaded with filler weight percentages both above and below the electric percolation threshold (EPT), were obtained by tunneling atomic force microscopy (TUNA) technique. The possibility to detect low currents also for the sample at lower concentration (0.1 wt%) confirms the good electrical performance of the nanocomposites and, consequently, the successful performed functionalization. The non-covalent modification significantly improves the thermal stability of the unfunctionalized G of about 70 °C, thus causing an increase in the composite oxidative thermostability since the evolution of CO2 shifts to higher values. Moreover, non-covalent functionalization proved to be impactful in imparting an overall enhancement of the nanocomposite mechanical properties due to good bonding between graphene and epoxy matrix, also showing a greater roughness which is decisive in influencing the interface adhesion efficiency.
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8
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Antibacterial Character of Cationic Polymers Attached to Carbon-Based Nanomaterials. NANOMATERIALS 2020; 10:nano10061218. [PMID: 32580474 PMCID: PMC7353121 DOI: 10.3390/nano10061218] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Revised: 06/19/2020] [Accepted: 06/19/2020] [Indexed: 01/17/2023]
Abstract
The preparation of hybrid polymeric systems based on carbon derivatives with a cationic polymer is described. The polymer used is a copolymer of a quaternizable methacrylic monomer with another dopamine-based monomer capable of anchoring to carbon compounds. Graphene oxide and graphene as well as hybrid polymeric systems were widely characterized by infrared, Raman and photoemission X-ray spectroscopies, electron scanning microscopy, zeta potential and thermal degradation. These allowed confirming the attachment of copolymer onto carbonaceous materials. Besides, the antimicrobial activity of hybrid polymeric systems was tested against Gram positive Staphylococcus aureus and Staphylococcus epidermidis and Gram negative Escherichia coli and Pseudomonas aeruginosa bacteria. The results showed the antibacterial character of these hybrid systems.
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9
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Spinelli G, Lamberti P, Tucci V, Guadagno L, Vertuccio L. Damage Monitoring of Structural Resins Loaded with Carbon Fillers: Experimental and Theoretical Study. NANOMATERIALS 2020; 10:nano10030434. [PMID: 32121350 PMCID: PMC7153371 DOI: 10.3390/nano10030434] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 02/21/2020] [Accepted: 02/28/2020] [Indexed: 11/16/2022]
Abstract
In the present study, nanocomposite materials for structural applications with self-sensing properties are proposed. In particular, suitable processing of epoxy resins filled with carbon nanotubes and expanded graphite characterized by very different aspect ratio leads to nanocomposite systems with high glass transition temperatures and remarkable values of the gauge factor. In particular, this notable property ranges between four, for composites filled with one-dimensional nanofiller, and 39 for composites with two-dimensional (2D) graphite derivatives. The greater sensitivity of the 2D system against permanent deformations is interpreted on the basis of an empirical mathematical model and morphological descriptions. The larger inter-contact area among the graphite layers determines a larger contact resistance change than that occurring among carbon nanotubes. The proposed systems turn out to be very advantageous in strain-sensor applications where damage detection is a key requirement to guarantee the reliability of the structures and the safety of the end-users.
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Affiliation(s)
- Giovanni Spinelli
- Department of Information and Electrical Engineering and Applied Mathematics, University of Salerno, Via Giovanni Paolo II, 84084 Fisciano (SA), Italy; (G.S.); (P.L.); (V.T.)
| | - Patrizia Lamberti
- Department of Information and Electrical Engineering and Applied Mathematics, University of Salerno, Via Giovanni Paolo II, 84084 Fisciano (SA), Italy; (G.S.); (P.L.); (V.T.)
| | - Vincenzo Tucci
- Department of Information and Electrical Engineering and Applied Mathematics, University of Salerno, Via Giovanni Paolo II, 84084 Fisciano (SA), Italy; (G.S.); (P.L.); (V.T.)
| | - Liberata Guadagno
- Department of Industrial Engineering, University of Salerno, Via Giovanni Paolo II, 84084 Fisciano (SA), Italy;
| | - Luigi Vertuccio
- Department of Industrial Engineering, University of Salerno, Via Giovanni Paolo II, 84084 Fisciano (SA), Italy;
- Correspondence:
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10
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Graphene Oxide and Oxidized Carbon Black as Catalyst for Crosslinking of Phenolic Resins. Polymers (Basel) 2019; 11:polym11081330. [PMID: 31405139 PMCID: PMC6722651 DOI: 10.3390/polym11081330] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Revised: 08/07/2019] [Accepted: 08/07/2019] [Indexed: 02/08/2023] Open
Abstract
Influence of different graphite-based nanofillers on crosslinking reaction of resorcinol, as induced by hexa(methoxymethyl)melamine, is studied. Curing reactions leading from low molecular mass compounds to crosslinked insoluble networks are studied by indirect methods based on Differential Scanning Calorimetry. Reported results show a catalytic activity of graphene oxide (eGO) on this reaction, comparable to that one already described in the literature for curing of benzoxazine. For instance, for an eGO content of 2 wt %, the exothermic crosslinking DSC peak (upon heating at 10 °C/min) shifted 6 °C. More relevantly, oxidized carbon black (oCB) is much more effective as catalyst of the considered curing reaction. In fact, for an oCB content of 2 wt %, the crosslinking DSC peak can be shifted more than 30 °C and a nearly complete crosslinking is already achieved by thermal treatment at 120 °C. The possible origin of the higher catalytic activity of oCB with respect to eGO is discussed.
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Spinelli G, Lamberti P, Tucci V, Kotsilkova R, Ivanov E, Menseidov D, Naddeo C, Romano V, Guadagno L, Adami R, Meisak D, Bychanok D, Kuzhir P. Nanocarbon/Poly(Lactic) Acid for 3D Printing: Effect of Fillers Content on Electromagnetic and Thermal Properties. MATERIALS 2019; 12:ma12152369. [PMID: 31349597 PMCID: PMC6695663 DOI: 10.3390/ma12152369] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Revised: 07/12/2019] [Accepted: 07/22/2019] [Indexed: 12/02/2022]
Abstract
Electromagnetic and thermal properties of a non-conventional polymer nanocomposite based on thermoplastic Polylactic acid (PLA, Ingeo™) filled, in different weight percentage, with multi-walled carbon nanotubes (MWCNTs), graphene nanoplatelets (GNPs), as well as a mixture of both fillers (MWCNTs/GNPs), are analyzed. The combination of notable electrical, thermal, and electromagnetic (EM) properties of the carbon fillers, in concentrations above the percolation threshold, together with the good processability of the PLA matrix gives rise to innovative filaments for 3D printing. In particular, the shielding efficiency (SE) in the frequency range 26–37 GHz of samples increases from 0.20 dB of unfilled PLA up to 13.4 dB for composites containing MWCNTs and GNPs, corresponding to 4% and 95% of SE, respectively. The thermal conductivity of the PLA loaded with 12 wt % of GNPs is 263% higher than that of the unfilled polymer, whereas an improvement of about 99% and 190% is detected for the PLA matrix loaded with MWCNTs and both fillers, respectively. The EM and thermal characterization is combined with a morphological investigation allowing us to correlate the dispersion states of the fillers within the polymer matrix with the observed EM and thermal properties. The EM and thermal characteristics exhibited by the nanocomposites make them suitable for packaging applications of electronic devices with electromagnetic interference (EMI) shielding and thermal dissipation features.
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Affiliation(s)
- Giovanni Spinelli
- Department of Information and Electrical Engineering and Applied Mathematics, University of Salerno, Via Giovanni Paolo II, 84084 Fisciano (SA), Italy.
| | - Patrizia Lamberti
- Department of Information and Electrical Engineering and Applied Mathematics, University of Salerno, Via Giovanni Paolo II, 84084 Fisciano (SA), Italy
| | - Vincenzo Tucci
- Department of Information and Electrical Engineering and Applied Mathematics, University of Salerno, Via Giovanni Paolo II, 84084 Fisciano (SA), Italy
| | - Rumiana Kotsilkova
- Institute of Mechanics, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., Block 4, 1113 Sofia, Bulgaria
| | - Evgeni Ivanov
- Institute of Mechanics, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., Block 4, 1113 Sofia, Bulgaria
- Research and Development of Nanomaterials and Nanotechnologies (NanoTech Lab Ltd.), Acad. G. Bonchev Str. Block 1, 1113 Sofia, Bulgaria
| | - Dzhihan Menseidov
- Institute of Mechanics, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., Block 4, 1113 Sofia, Bulgaria
| | - Carlo Naddeo
- Department of Industrial Engineering, University of Salerno, Via Giovanni Paolo II, 84084 Fisciano (SA), Italy
| | - Vittorio Romano
- Department of Industrial Engineering, University of Salerno, Via Giovanni Paolo II, 84084 Fisciano (SA), Italy
| | - Liberata Guadagno
- Department of Industrial Engineering, University of Salerno, Via Giovanni Paolo II, 84084 Fisciano (SA), Italy
| | - Renata Adami
- Department of Industrial Engineering, University of Salerno, Via Giovanni Paolo II, 84084 Fisciano (SA), Italy
| | - Darya Meisak
- Institute for Nuclear Problems of Belarusian State University, Bobruiskaya 11, 220030 Minsk, Belarus
| | - Dzmitry Bychanok
- Institute for Nuclear Problems of Belarusian State University, Bobruiskaya 11, 220030 Minsk, Belarus
- Radioelectronics Department, Faculty of Radiophysics, Tomsk State University, 36 Lenin Prospekt, Tomsk 634050, Russia
| | - Polina Kuzhir
- Institute for Nuclear Problems of Belarusian State University, Bobruiskaya 11, 220030 Minsk, Belarus
- Radioelectronics Department, Faculty of Radiophysics, Tomsk State University, 36 Lenin Prospekt, Tomsk 634050, Russia
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12
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Carbon-Based Aeronautical Epoxy Nanocomposites: Effectiveness of Atomic Force Microscopy (AFM) in Investigating the Dispersion of Different Carbonaceous Nanoparticles. Polymers (Basel) 2019; 11:polym11050832. [PMID: 31072028 PMCID: PMC6572032 DOI: 10.3390/polym11050832] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2019] [Revised: 04/29/2019] [Accepted: 05/02/2019] [Indexed: 11/16/2022] Open
Abstract
The capability of Atomic Force Microscopy (AFM) to characterize composite material interfaces can help in the design of new carbon-based nanocomposites by providing useful information on the structure-property relationship. In this paper, the potentiality of AFM is explored to investigate the dispersion and the morphological features of aeronautical epoxy resins loaded with several carbon nanostructured fillers. Fourier Transform Infrared Spectroscopy (FTIR) and thermal investigations of the formulated samples have also been performed. The FTIR results show that, among the examined nanoparticles, exfoliated graphite (EG) with a predominantly two-dimensional (2D) shape favors the hardening process of the epoxy matrix, increasing its reaction rate. As evidenced by the FTIR signal related to the epoxy stretching frequency (907 cm-1), the accelerating effect of the EG sample increases as the filler concentration increases. This effect, already observable for curing treatment of 60 min conducted at the low temperature of 125 °C, suggests a very fast opening of epoxy groups at the beginning of the cross-linking process. For all the analyzed samples, the percentage of the curing degree (DC) goes beyond 90%, reaching up to 100% for the EG-based nanocomposites. Besides, the addition of the exfoliated graphite enhances the thermostability of the samples up to about 370 °C, even in the case of very low EG percentages (0.05% by weight).
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Guadagno L, Naddeo C, Raimondo M, Speranza V, Pantani R, Acquesta A, Carangelo A, Monetta T. UV Irradiated Graphene-Based Nanocomposites: Change in the Mechanical Properties by Local HarmoniX Atomic Force Microscopy Detection. MATERIALS (BASEL, SWITZERLAND) 2019; 12:E962. [PMID: 30909458 PMCID: PMC6470810 DOI: 10.3390/ma12060962] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Revised: 03/12/2019] [Accepted: 03/19/2019] [Indexed: 11/17/2022]
Abstract
Epoxy based coatings are susceptible to ultra violet (UV) damage and their durability can be significantly reduced in outdoor environments. This paper highlights a relevant property of graphene-based nanoparticles: Graphene Nanoplatelets (GNPs) incorporated in an epoxy-based free-standing film determine a strong decrease of the mechanical damages caused by UV irradiation. The effects of UV light on the morphology and mechanical properties of the solidified nanocharged epoxy films are investigated by Atomic Force Microscopy (AFM), in the acquisition mode "HarmoniX." Nanometric-resolved maps of the mechanical properties of the multi-phase material evidence that the incorporation of low percentages, between 0.1% and 1.0% by weight, of graphene nanoplatelets (GNPs) in the polymeric film causes a relevant enhancement in the mechanical stability of the irradiated films. The beneficial effect progressively increases with increasing GNP percentage. The paper also highlights the potentiality of AFM microscopy, in the acquisition mode "HarmoniX" for studying multiphase polymeric systems.
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Affiliation(s)
- Liberata Guadagno
- Department of Industrial Engineering, University of Salerno, Via Giovanni Paolo II, 132, Salerno, 84084 Fisciano, Italy.
| | - Carlo Naddeo
- Department of Industrial Engineering, University of Salerno, Via Giovanni Paolo II, 132, Salerno, 84084 Fisciano, Italy.
| | - Marialuigia Raimondo
- Department of Industrial Engineering, University of Salerno, Via Giovanni Paolo II, 132, Salerno, 84084 Fisciano, Italy.
| | - Vito Speranza
- Department of Industrial Engineering, University of Salerno, Via Giovanni Paolo II, 132, Salerno, 84084 Fisciano, Italy.
| | - Roberto Pantani
- Department of Industrial Engineering, University of Salerno, Via Giovanni Paolo II, 132, Salerno, 84084 Fisciano, Italy.
| | - Annalisa Acquesta
- Department of Chemical Engineering, Materials and Industrial Production, University of Napoli Federico II, Piazzale Tecchio 80, 80125 Napoli, Italy.
| | - Anna Carangelo
- Department of Chemical Engineering, Materials and Industrial Production, University of Napoli Federico II, Piazzale Tecchio 80, 80125 Napoli, Italy.
| | - Tullio Monetta
- Department of Chemical Engineering, Materials and Industrial Production, University of Napoli Federico II, Piazzale Tecchio 80, 80125 Napoli, Italy.
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14
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Vittore A, Acocella MR, Guerra G. Edge-Oxidation of Graphites by Hydrogen Peroxide. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:2244-2250. [PMID: 30624074 DOI: 10.1021/acs.langmuir.8b03489] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
A simple and eco-friendly procedure of edge oxidation of high-surface area graphites, based on hydrogen peroxide treatments at 60 °C, is presented. Already, short-term treatments lead to O/C weight ratios higher than 0.1, leaving unaltered interlayer spacing and correlation length. This clearly indicates that all oxidized groups are located on exposed sites (mainly on lateral edges) of the graphitic layers. Short-term H2O2 treatments, as expected, increase hydrophilicity and reduce thermal stability with respect to the starting graphite. Long-term treatments, on the contrary, reduce hydrophilicity and increase thermal stability with respect to the starting graphite, mainly due to surface area reduction associated with the oxidation procedure. Exfoliation of a substantial fraction of the obtained edge-oxidized graphite can be achieved by simple procedures of dispersion and sonication in water.
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Affiliation(s)
- Aniello Vittore
- Department of Chemistry and Biology and INSTM Research Unit , Università di Salerno , Fisciano 84084 , Salerno , Italy
| | - Maria Rosaria Acocella
- Department of Chemistry and Biology and INSTM Research Unit , Università di Salerno , Fisciano 84084 , Salerno , Italy
| | - Gaetano Guerra
- Department of Chemistry and Biology and INSTM Research Unit , Università di Salerno , Fisciano 84084 , Salerno , Italy
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15
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Vittore A, Acocella MR, Guerra G. Graphite functionalization by ball milling with sulfur. SN APPLIED SCIENCES 2019. [DOI: 10.1007/s42452-019-0179-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
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16
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Acocella MR, Guerra G. Graphene-Based Carbocatalysts for Thermoset Polymers and for Diastereoselective and Enantioselective Organic Synthesis. ChemCatChem 2018. [DOI: 10.1002/cctc.201702015] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Maria Rosaria Acocella
- Department of Chemistry and Biology “Adolfo Zambelli”; University of Salerno; Via Giovanni Paolo II, 132 Fisciano Salerno SA Italy
| | - Gaetano Guerra
- Department of Chemistry and Biology “Adolfo Zambelli”; University of Salerno; Via Giovanni Paolo II, 132 Fisciano Salerno SA Italy
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17
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Miraftab R, Karimi B, Bahlakeh G, Ramezanzadeh B. Complementary experimental and quantum mechanics approaches for exploring the mechanical characteristics of epoxy composites loaded with graphene oxide-polyaniline nanofibers. J IND ENG CHEM 2017. [DOI: 10.1016/j.jiec.2017.05.006] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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18
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Omah AD, Okorie BA, Omah EC, Ezema IC, Aigbodion VS, Orji UU. Experimental correlation between varying cassava cortex and dielectric properties in epoxy/cassava cortex dielectric particulates composites. PARTICULATE SCIENCE AND TECHNOLOGY 2017. [DOI: 10.1080/02726351.2017.1307888] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- A. D. Omah
- Department of Metallurgical and Materials Engineering, University of Nigeria Nsukka
| | - B. A. Okorie
- Department of Metallurgical and Materials Engineering, University of Nigeria Nsukka
| | - E. C. Omah
- Department of Food Science and Technology, University of Nigeria Nsukka
| | - I. C. Ezema
- Department of Metallurgical and Materials Engineering, University of Nigeria Nsukka
| | - V. S. Aigbodion
- Department of Metallurgical and Materials Engineering, University of Nigeria Nsukka
| | - U. U. Orji
- Department of Metallurgical and Materials Engineering, University of Nigeria Nsukka
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19
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Sahoo SK, Ray BC, Mallik A. Role of electrochemically in-house synthesized and functionalized graphene nanofillers in the structural performance of epoxy matrix composites. Phys Chem Chem Phys 2017; 19:16219-16230. [PMID: 28607973 DOI: 10.1039/c7cp01615h] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The present study focuses on the intriguing enhancement in the mechanical properties of an epoxy-based composite structure resulting from the incorporation of in-house synthesized functionalized graphene nanosheets (f-GNSs) as nanofillers. The f-GNSs were obtained by anionic electrochemical intercalation and exfoliation with 2 M H2SO4, HClO4, and HNO3 protic electrolytes. The structural properties of the as-synthesized GNSs were analyzed by XRD and Raman spectroscopy. The (002) and (001) lattice planes of graphene and graphene oxide are observed at around 24.5° and 11° (2θ), respectively, in the XRD spectra. The characteristic peaks at around 1345, 1590, and 2700 cm-1 correspond to the D, G, and 2D bands of the GNSs in the Raman spectra. Quantification of the functional groups and sp2 contents in the GNSs were further analyzed by XPS. Morphological characterization of the f-GNSs reveals that the exfoliated carbon sheets consist of 2-8 layers. The composites are then fabricated by addition of these f-GNSs nanofillers, and the effect of the wt% of the nanofillers on the mechanical properties of the composites is analyzed with the three-point bend test and fractography analysis through interfacial morphological analysis. The addition of 0.1 wt% of nitric-acid-exfoliated f-GNSs nanofiller results in maximum increases of 42.6% and 28.2% in the flexural strengths of neat epoxy resin and glass fiber/epoxy polymer composite structures, respectively. Similarly, the moduli increase by 33.5% and 57.7% in the neat epoxy resin and glass fiber/epoxy polymer composite structures, respectively. The effect of epoxy/f-GNSs interfacial bonding in the composite structure was studied by DSC analysis.
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Affiliation(s)
- Sumanta Kumar Sahoo
- Electrometallurgy and Corrosion Laboratory, Metallurgical and Materials Engineering Department, National Institute of Technology Rourkela, Rourkela 769 008, Odisha, India.
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20
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Liparoti S, Sorrentino A, Speranza V, Titomanlio G. Multiscale mechanical characterization of iPP injection molded samples. Eur Polym J 2017. [DOI: 10.1016/j.eurpolymj.2017.03.010] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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21
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Guadagno L, Naddeo C, Raimondo M, Barra G, Vertuccio L, Russo S, Lafdi K, Tucci V, Spinelli G, Lamberti P. Influence of carbon nanoparticles/epoxy matrix interaction on mechanical, electrical and transport properties of structural advanced materials. NANOTECHNOLOGY 2017; 28:094001. [PMID: 28135206 DOI: 10.1088/1361-6528/aa583d] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The focus of this study is to design new nano-modified epoxy formulations using carbon nanofillers, such as carbon nanotubes, carbon nanofibers and graphene-based nanoparticles (CpEG), that reduce the moisture content and provide additional functional performance. The chemical structure of epoxy mixture, using a non-stoichiometric amount of hardener, exhibits unique properties in regard to the water sorption for which the equilibrium concentration of water (C eq) is reduced up to a maximum of 30%. This result, which is very relevant for several industrial applications (aeronautical, shipbuilding industries, wind turbine blades, etc), is due to a strong reduction of the polar groups and/or sites responsible to bond water molecules. All nanofillers are responsible of a second phase at lower glass transition temperature (Tg). Compared with other carbon nanofillers, functionalized graphene-based nanoparticles exhibit the best performance in the multifunctionality. The lowest moisture content, the high performance in the mechanical properties, the low electrical percolation threshold (EPT) have been all ascribed to particular arrangements of the functionalized graphene sheets embedded in the polymeric matrix. Exfoliation degree and edge carboxylated groups are responsible of self-assembled architectures which entrap part of the resin fraction hindering the interaction of water molecules with the polar sites of the resin, also favouring the EPT paths and the attractive/covalent interactions with the matrix.
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Affiliation(s)
- Liberata Guadagno
- Department of Industrial Engineering, University of Salerno, Via Giovanni Paolo II, 132, I-84084, Fisciano (SA), Italy
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22
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Raimondo M, Guadagno L, Naddeo C, Longo P, Mariconda A, Agovino A. New structure of diamine curing agent for epoxy resins with self-restoration ability: Synthesis and spectroscopy characterization. J Mol Struct 2017. [DOI: 10.1016/j.molstruc.2016.10.060] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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23
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Corcione CE, Acocella MR, Giuri A, Maffezzoli A. Epoxy Resin Catalyzed by Graphite-Based Nanofillers. INT POLYM PROC 2016. [DOI: 10.3139/217.3225] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Abstract
Graphene stacks/epoxy nanocomposites were produced and characterized in order to analyse the effect of different graphene precursors on cure reaction of a model epoxy matrix. A kinetic analysis of the cure mechanism of the epoxy resin associated to the catalytical activity of the graphite based fillers was performed by isothermal DSC measurements. The DSC results showed that the addition of all graphite based fillers greatly increased the enthalpy of epoxy reaction and the reaction rate, confirming the presence of a catalytic activity of graphitic layers on the crosslinking reaction between the epoxy resin components (epoxide oligomer and di-amine). A kinetic modelling analysis, arising from an autocatalyzed reaction mechanism, was finally applied to isothermal DSC data, in order to predict the cure mechanism of the epoxy resin in presence of the graphite based nanofiller.
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Affiliation(s)
- C. Esposito Corcione
- Dipartimento di Ingegneria dell'Innovazione , Università del Salento, Lecce , Italy
| | - M. R. Acocella
- Dipartimento di Chimica e Biologia e Unità di Ricerca INSTM , Università di Salerno, Fisciano , Italy
| | - A. Giuri
- Dipartimento di Ingegneria dell'Innovazione , Università del Salento, Lecce , Italy
| | - A. Maffezzoli
- Dipartimento di Ingegneria dell'Innovazione , Università del Salento, Lecce , Italy
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24
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Yan N, Capezzuto F, Lavorgna M, Buonocore GG, Tescione F, Xia H, Ambrosio L. Borate cross-linked graphene oxide-chitosan as robust and high gas barrier films. NANOSCALE 2016; 8:10783-91. [PMID: 27168418 DOI: 10.1039/c6nr00377j] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Chitosan (CS) is one of the most promising polymers due to its biocompatibility, biodegradability, and natural abundance. However, its poor mechanical and barrier properties make it difficult to satisfy a wide range of applications. Herein, borate ions, originating from the hydrolysis of sodium tetraborate decahydrate (borax), have been used to crosslink chitosan and graphene oxide (GO) nanocomposites. Chitosan films consisting of 1.0 wt% boron and 1.0 wt% GO exhibit a significant improvement in both the toughness and oxygen barrier properties compared to pristine chitosan. In particular the tensile strength of the samples after thermal treatment increases by ∼160% compared to pristine chitosan, whereas their oxygen permeability reduces by ∼90%. This is ascribed to the chemical crosslinking between chitosan and GO nanoplatelets through borate ions, as well as the formation of a layered morphology with graphene nanoplatelets oriented parallel to the sample surface. The exceptional robust and high gas barrier film has promising application in the packaging industry. The borate-crosslinking chemistry represents the potential strategy for improving properties of other polymer nanocomposites.
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Affiliation(s)
- Ning Yan
- Institute of Polymers, Composites and Biomaterials, National Research Council, P.le Fermi, 1-80055 Portici, NA, Italy. and Xi'an Modern Chemistry Research Institute, Xi'an 710065, China
| | - Filomena Capezzuto
- Institute of Polymers, Composites and Biomaterials, National Research Council, P.le Fermi, 1-80055 Portici, NA, Italy.
| | - Marino Lavorgna
- Institute of Polymers, Composites and Biomaterials, National Research Council, P.le Fermi, 1-80055 Portici, NA, Italy.
| | - Giovanna G Buonocore
- Institute of Polymers, Composites and Biomaterials, National Research Council, P.le Fermi, 1-80055 Portici, NA, Italy.
| | - Fabiana Tescione
- Institute of Polymers, Composites and Biomaterials, National Research Council, P.le Fermi, 1-80055 Portici, NA, Italy.
| | - Hesheng Xia
- State Key Laboratory of Polymer Materials Engineering, Polymer Research Institute of Sichuan University, Chengdu 610065, China.
| | - Luigi Ambrosio
- Institute of Polymers, Composites and Biomaterials, National Research Council, P.le Fermi, 1-80055 Portici, NA, Italy.
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25
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Acocella MR, Corcione CE, Giuri A, Maggio M, Maffezzoli A, Guerra G. Graphene oxide as a catalyst for ring opening reactions in amine crosslinking of epoxy resins. RSC Adv 2016. [DOI: 10.1039/c6ra00485g] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The influence of different graphite-based nanofillers on epoxide ring opening reactions, as induced by amines for diglycidyl ether of bisphenol A (DGEBA), is studied.
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Affiliation(s)
- M. R. Acocella
- Department of Chemistry and Biology and INSTM Research Unit
- Università di Salerno
- Fisciano
- Italy
| | | | - A. Giuri
- Dipartimento di Ingegneria dell'Innovazione
- Università del Salento
- Lecce
- Italy
| | - M. Maggio
- Department of Chemistry and Biology and INSTM Research Unit
- Università di Salerno
- Fisciano
- Italy
| | - A. Maffezzoli
- Dipartimento di Ingegneria dell'Innovazione
- Università del Salento
- Lecce
- Italy
| | - G. Guerra
- Department of Chemistry and Biology and INSTM Research Unit
- Università di Salerno
- Fisciano
- Italy
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26
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Bu Q, Zhan Y, He F, Lavorgna M, Xia H. Stretchable conductive films based on carbon nanomaterials prepared by spray coating. J Appl Polym Sci 2015. [DOI: 10.1002/app.43243] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- Qiang Bu
- State Key Laboratory of Polymer Materials Engineering; Polymer Research Institute, Sichuan University; Chengdu 610065 People's Republic of China
| | - Yanhu Zhan
- State Key Laboratory of Polymer Materials Engineering; Polymer Research Institute, Sichuan University; Chengdu 610065 People's Republic of China
| | - Fangfang He
- State Key Laboratory of Polymer Materials Engineering; Polymer Research Institute, Sichuan University; Chengdu 610065 People's Republic of China
| | - Marino Lavorgna
- Institute of Polymers, Composites and Biomaterials, National Research Council; Piazzale Fermi 1 80055 Portici (NA) Italy
| | - Hesheng Xia
- State Key Laboratory of Polymer Materials Engineering; Polymer Research Institute, Sichuan University; Chengdu 610065 People's Republic of China
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27
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Yan N, Capezzuto F, Buonocore GG, Lavorgna M, Xia H, Ambrosio L. Gas-Barrier Hybrid Coatings by the Assembly of Novel Poly(vinyl alcohol) and Reduced Graphene Oxide Layers through Cross-Linking with Zirconium Adducts. ACS APPLIED MATERIALS & INTERFACES 2015; 7:22678-22685. [PMID: 26406566 DOI: 10.1021/acsami.5b07529] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Gas-barrier materials obtained by coating poly(ethylene terephthalate) (PET) substrates have already been studied in the recent literature. However, because of the benefits of using cheaper, biodegradable, and nonpolar polymers, multilayered hybrid coatings consisting of alternate layers of reduced graphene oxide (rGO) nanosheets and a novel high amorphous vinyl alcohol (HAVOH) with zirconium (Zr) adducts as binders were successfully fabricated through a layer-by-layer (LbL) assembly approach. Atomic force microscopy analysis showed that rGO nanoplatelets were uniformly dispersed over the HAVOH polymer substrate. Scanning and transmission electron microscopies revealed that multilayer (HAVOH/Zr/rGO)n hybrid coatings exhibited a brick-wall structure with HAVOH and rGO as buildings blocks. It has been shown that 40 layers of HAVOH/Zr/rGO ultrathin films deposited on PET substrates lead to a decrease of 1 order of magnitude of oxygen permeability with respect to the pristine PET substrate. This is attributed to the effect of zirconium polymeric adducts, which enhance the assembling efficiency of rGO and compact the layers, as confirmed by NMR characterization, resulting in a significant increment of the oxygen-transport pathways. Because of their high barrier properties and high flexibility, these films are promising candidates in a variety of applications such as packaging, selective gas films, and protection of flexible electronics.
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Affiliation(s)
- Ning Yan
- Institute of Polymers, Composites and Biomaterials, National Research Council , Piazzalle Fermi, 1-80055 Portici, Naples, Italy
- Xi'an Modern Chemistry Research Institute , Xi'an 710065, China
| | - Filomena Capezzuto
- Institute of Polymers, Composites and Biomaterials, National Research Council , Piazzalle Fermi, 1-80055 Portici, Naples, Italy
| | - Giovanna G Buonocore
- Institute of Polymers, Composites and Biomaterials, National Research Council , Piazzalle Fermi, 1-80055 Portici, Naples, Italy
| | - Marino Lavorgna
- Institute of Polymers, Composites and Biomaterials, National Research Council , Piazzalle Fermi, 1-80055 Portici, Naples, Italy
| | - Hesheng Xia
- State Key Laboratory of Polymer Materials Engineering, Polymer Research Institute of Sichuan University , Chengdu 610065, China
| | - Luigi Ambrosio
- Institute of Polymers, Composites and Biomaterials, National Research Council , Piazzalle Fermi, 1-80055 Portici, Naples, Italy
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29
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Vertuccio L, Russo S, Raimondo M, Lafdi K, Guadagno L. Influence of carbon nanofillers on the curing kinetics of epoxy-amine resin. RSC Adv 2015. [DOI: 10.1039/c5ra14343h] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Variation of the activation energy with conversion obtained by “advanced isoconversional method”.
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Affiliation(s)
- L. Vertuccio
- Department of Industrial Engineering – DIIn
- University of Salerno
- 132–84084 Fisciano
- Italy
| | | | - M. Raimondo
- Department of Industrial Engineering – DIIn
- University of Salerno
- 132–84084 Fisciano
- Italy
| | | | - L. Guadagno
- Department of Industrial Engineering – DIIn
- University of Salerno
- 132–84084 Fisciano
- Italy
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