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Chen R, Luo C. Stretching effect on intrachain conformational ordering of polymers: A steered molecular dynamics simulation. POLYMER 2022. [DOI: 10.1016/j.polymer.2022.125106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Yamamoto T. Chiral selecting crystallization of helical polymers: A molecular dynamics simulation for the POM-like bare helix. J Chem Phys 2022; 157:014901. [DOI: 10.1063/5.0097112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Polymer crystallization has long been a fascinating problem and is still attracting many researchers. Most of the previous simulations are concentrated on clarifying the universal aspects of polymer crystallization using model linear polymers such as polyethylene. We are recently focusing on a nearly untouched but very interesting problem of chiral selecting crystallization in helical polymers. We previously proposed a stepwise approach using two kinds of helical polymers, simple "bare" helical polymers made of backbone atoms only such as polyoxymethylene (POM) and "general" helical polymers containing complicated side groups such as isotactic polypropylene (iPP). We have already reported on the crystallization in oligomeric POM-like helix but have observed only weak chiral selectivity during crystallization. In the present paper, we investigate the crystallization of sufficiently long POM-like polymer both from the isotropic melt and from the highly stretched melt. We find in both cases that the polymer shows a clear chiral selecting crystallization. Especially the observation of a single crystal growing from the isotropic melt is very illuminating. It shows that the crystal thickness and the crystal chirality is closely correlated; thicker crystals show definite chirality while thinner ones are mostly mixtures of the R- and the L- handed stems. The single crystal is found to have a marked lenticular shape, where the thinner growth front, since being made of the mixture, shows no chiral selectivity. Final chiral crystal is found to be completed through helix reversal processes within thicker regions.
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Affiliation(s)
- Takashi Yamamoto
- Department of Physics and Informatics, Yamaguchi University, Japan
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Luo C. A challenging topic of computer simulations: Polymorphism in polymers. POLYMER CRYSTALLIZATION 2020. [DOI: 10.1002/pcr2.10109] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- Chuanfu Luo
- State Key Laboratory of Polymer Physics and ChemistryChangchun Institute of Applied Chemistry, Chinese Academy of Sciences Changchun China
- University of Science and Technology of China Hefei China
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Luo BJ, Li HF, Zhang WY, Zhou CB, Li JQ, Lu CH, He XH, Jiang SC. Mechanistic insights into the shear effects on isotactic polypropylene crystallization containing β-nucleating agent. CHINESE JOURNAL OF POLYMER SCIENCE 2017. [DOI: 10.1007/s10118-017-1912-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Romanos NA, Theodorou DN. Melting Point and Solid–Liquid Coexistence Properties of α1 Isotactic Polypropylene as Functions of Its Molar Mass: A Molecular Dynamics Study. Macromolecules 2016. [DOI: 10.1021/acs.macromol.6b00819] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Nikolaos A. Romanos
- School of Chemical Engineering, Department of Materials Science & Engineering, National Technical University of Athens, 9 Heroon Polytechniou Street, Zografou Campus, 157 80 Athens, Greece
| | - Doros N. Theodorou
- School of Chemical Engineering, Department of Materials Science & Engineering, National Technical University of Athens, 9 Heroon Polytechniou Street, Zografou Campus, 157 80 Athens, Greece
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Luo B, Li H, Zhou C, Zhang W, Li J, He X, Jiang S. Mechanistic Insights into the Shear-Inducedβ-Form Crystal Formation of iPP. MACROMOL CHEM PHYS 2016. [DOI: 10.1002/macp.201500542] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Baojing Luo
- School of Materials Science and Engineering; Tianjin University; Tianjin 300072 P. R. China
| | - Hongfei Li
- State Key Laboratory of Polymer Physics and Chemistry; Changchun Institute of Applied Chemistry; Chinese Academy of Sciences; Changchun 130022 P. R. China
| | - Chengbo Zhou
- School of Materials Science and Engineering; Tianjin University; Tianjin 300072 P. R. China
| | - Wenyang Zhang
- School of Materials Science and Engineering; Tianjin University; Tianjin 300072 P. R. China
| | - Jingqing Li
- School of Materials Science and Engineering; Tianjin University; Tianjin 300072 P. R. China
| | - Xuehao He
- Department of Chemistry; School of Science; Tianjin University; Tianjin 300072 P. R. China
| | - Shichun Jiang
- School of Materials Science and Engineering; Tianjin University; Tianjin 300072 P. R. China
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Chen Q, Sirota EB, Zhang M, Chung TCM, Milner ST. Free Surfaces Overcome Superheating in Simulated Melting of Isotactic Polypropylene. Macromolecules 2015. [DOI: 10.1021/acs.macromol.5b02030] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | - Eric B. Sirota
- ExxonMobil Research and Engineering, 1545 Route 22 East, Annandale, New Jersey 08809, United States
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Yamamoto T. Molecular Dynamics of Crystallization in a Helical Polymer Isotactic Polypropylene from the Oriented Amorphous State. Macromolecules 2014. [DOI: 10.1021/ma500307h] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Takashi Yamamoto
- Department of Physics and Informatics, Yamaguchi University, Yamaguchi 753-8512, Yamaguchi, Japan
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