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Calucci L, Pizzanelli S, Mandoli A, Birczyński A, Lalowicz ZT, De Monte C, Ricci L, Bronco S. Unravelling Main- and Side-Chain Motions in Polymers with NMR Spectroscopy and Relaxometry: The Case of Polyvinyl Butyral. Polymers (Basel) 2021; 13:2686. [PMID: 34451226 PMCID: PMC8398131 DOI: 10.3390/polym13162686] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Revised: 07/30/2021] [Accepted: 08/06/2021] [Indexed: 11/19/2022] Open
Abstract
Polyvinyl butyral (PVB) is an amorphous polymer employed in many technological applications. In order to highlight the relationships between macroscopic properties and dynamics at a microscopic level, motions of the main-chain and of the propyl side-chains were investigated between Tg - 288 °C and Tg + 55 °C, with Tg indicating the glass transition temperature. To this aim, a combination of solid state Nuclear Magnetic Resonance (NMR) methods was applied to two purposely synthesized PVB isotopomers: one fully protonated and the other perdeuterated on the side-chains. 1H time domain NMR and 1H field cycling NMR relaxometry experiments, performed across and above Tg, revealed that the dynamics of the main-chain corresponds to the α-relaxation associated to the glass transition, which was previously characterized by dielectric spectroscopy. A faster secondary relaxation was observed for the first time and ascribed to side-chains. The geometry and rate of motions of the different groups in the side-chains were characterized below Tg by 2H NMR spectroscopy.
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Affiliation(s)
- Lucia Calucci
- Istituto di Chimica dei Composti OrganoMetallici, Consiglio Nazionale delle Ricerche—CNR, Via G. Moruzzi 1, 56124 Pisa, Italy;
- Centro per l’Integrazione della Strumentazione Scientifica dell’Università di Pisa (CISUP), Lungarno Pacinotti 43/44, 56126 Pisa, Italy
| | - Silvia Pizzanelli
- Istituto di Chimica dei Composti OrganoMetallici, Consiglio Nazionale delle Ricerche—CNR, Via G. Moruzzi 1, 56124 Pisa, Italy;
- Centro per l’Integrazione della Strumentazione Scientifica dell’Università di Pisa (CISUP), Lungarno Pacinotti 43/44, 56126 Pisa, Italy
| | - Alessandro Mandoli
- Dipartimento di Chimica e Chimica Industriale, Università di Pisa, Via G. Moruzzi 13, 56124 Pisa, Italy;
| | - Artur Birczyński
- Institute of Technology, The Pedagogical University of Kraków, Podchorążych 2, 30-084 Krakow, Poland;
| | - Zdzisław T. Lalowicz
- Institute of Nuclear Physics, Polish Academy of Sciences, ul. Radzikowskiego 152, 31-342 Krakow, Poland;
| | - Cristina De Monte
- Istituto per i Processi Chimico-Fisici, Consiglio Nazionale delle Ricerche—CNR, Via G. Moruzzi 1, 56124 Pisa, Italy; (C.D.M.); (L.R.); (S.B.)
| | - Lucia Ricci
- Istituto per i Processi Chimico-Fisici, Consiglio Nazionale delle Ricerche—CNR, Via G. Moruzzi 1, 56124 Pisa, Italy; (C.D.M.); (L.R.); (S.B.)
| | - Simona Bronco
- Istituto per i Processi Chimico-Fisici, Consiglio Nazionale delle Ricerche—CNR, Via G. Moruzzi 1, 56124 Pisa, Italy; (C.D.M.); (L.R.); (S.B.)
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Lazarenko MM, Alekseev AN, Alekseev SA, Yablochkova KS, Bokhvan SI, Demidiuk OF, Lazarenko MV. Topological solitons in aliphatic systems with a restricted translational mobility. Chem Phys 2020. [DOI: 10.1016/j.chemphys.2020.110959] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Zhang T, Hsieh WY, Daneshvar F, Liu C, Rwei SP, Sue HJ. Copper(I)-alkylamine mediated synthesis of copper nanowires. NANOSCALE 2020; 12:17437-17449. [PMID: 32797131 DOI: 10.1039/d0nr04778c] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Formation of a Cu(i)-alkylamine complex is found to be the key step for Cu(ii) ions to reduce to Cu(0) in the presence of glucose. Also, alkylamines in Cu nanowire synthesis serve triple roles as a reducing, complexation and capping agent. Alkylamines reduce Cu(ii) to Cu(i) at above 100 °C and protect the Cu(i) by forming a Cu ion-alkylamine coordination complex with a 1 : 2 ratio in an aqueous solution. With respect to the 1 : 2 complex ratio, the additional free alkylamines ensure a stable Cu(i)-alkylamine complex. After completion of Cu(i)-Cu(0) reduction by glucose, alkylamines remain on Cu(0) seeds to regulate the anisotropic growth of Cu nanocrystals. Long-chain (≥C16) alkylamines are found to help produce high-quality Cu nanowires, while short-chain (≤C12) alkylamines only produce CuO products. Furthermore, Cu nanowire synthesis is found to be sensitive to additional chemicals as they may destabilize Cu ion-alkylamine complexes. By comparing the Cu(i)-alkylamine and Maillard reaction mediated mechanism, the complete Cu nanowire synthesis process using glucose is revealed.
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Affiliation(s)
- Tan Zhang
- Polymer Technology Center, Department of Materials Science and Engineering, Texas A&M University, College Station, TX 77843, USA.
| | - Wen-Yi Hsieh
- Department of Molecular Science and Engineering, Research and Development Center for Smart Textile Technology, National Taipei University of Technology, Taipei 10608, Taiwan
| | - Farhad Daneshvar
- Polymer Technology Center, Department of Materials Science and Engineering, Texas A&M University, College Station, TX 77843, USA.
| | - Cong Liu
- Polymer Technology Center, Department of Materials Science and Engineering, Texas A&M University, College Station, TX 77843, USA.
| | - Syang-Peng Rwei
- Department of Molecular Science and Engineering, Research and Development Center for Smart Textile Technology, National Taipei University of Technology, Taipei 10608, Taiwan
| | - Hung-Jue Sue
- Polymer Technology Center, Department of Materials Science and Engineering, Texas A&M University, College Station, TX 77843, USA.
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