Poly(lactic acid). Группа авторов
Читать онлайн книгу.
from the melt are still ambiguous for these polyesters. Another important aspect of the biodegradable polyesters is related to the microscopically viewed investigation of their biodegradation process in the presence of bacteria. As described briefly about the phase transition of PHB, the role of taut tie chains passing through the stacked lamellae (or the rigid amorphous fraction, RAF) must be also revealed in association with the structure‐property relation of the bulk samples [72].
In the long history of the biodegradable polyesters, many papers have reported their structural information. However, reliability of the crystal structure and chain conformation reported in the literature remain elusive. Different from the single crystals of low‐molecular‐weight compounds, the low accuracy of the analyzed structure might be fatal for the semicrystalline polymer substances because the poor X‐ray diffraction data of small and broad diffraction spots are collected at best. It is important to always check whether the structure information is consistent with other experimental data, as exemplified from several case studies presented in this chapter.
ACKNOWLEDGEMENTS
The author Kohji Tashiro, is grateful for many researchers who collaborated and encouraged him in the structure studies of PLA: Dr. Hideto Tsuji (Toyohashi University of Technology, Japan), Dr. Takashi Ohhara (Japan Atomic Energy Agency), Dr. Nobuo Niimura (Ibaraki University, Japan), Dr. Tomoji Ozeki (Tokyo Institute of Technology, (present) Nihon University, Japan), Dr. Kaewkan Wasanasuk (Toyota Technological Institute, (present) PTT Public Co., Thailand), Dr. Makoto Hanesaka (Toyota Technological Institute), Dr. Tetsuo Kanamoto (Tokyo University of Science,), Mr. Naoto Kouno (Toyota Technological Institute), Dr. Jun Koshobu and Mr. Keisuke Watanabe (Japan Spectroscopic Co. Ltd., Japan), Dr. Suwabun Chirachanchai (Chulalongkorn University, Thailand), Dr. Piyawanee Jariyasakoolroj (Chulalongkorn University, (present) Kasetsart University, Thailand), Dr. Wannee Chinsirikul (National Metal and Materials Technology Center, Thailand), and Dr. Hiroko Yamamoto (Toyota Technological Institute, (present) Aichi Synchrotron Radiation Center).
This work was supported by “the Strategic Project to Support the Formation of Research Base at Private University (2010–2014) and (2015–2019)” of MEXT, Japan, and also by the National Natural Science Foundation of China 22073015.
REFERENCES
1 1. S. Iannace, L. Nicolais, Isothermal crystallization and chain mobility of poly(l‐lactide), J. Appl. Polym. Sci. 1997, 64, 911–919.
2 2. G. Kokturk, E. Piskin, T. F. Serhatkulu, M. Cakmak, Evolution of phase behavior and orientation in uniaxially deformed polylactic acid films, Polym. Eng. Sci. 2002, 42, 1619–1628.
3 3. J. Hu, T. Zhang, M. Gu, X. Chen, J. Zhang, Spectroscopic analysis on cold drawing‐induced PLLA mesophase, Polymer 2012, 53, 4922–4926.
4 4. J. Zhang, Y. Duan, A. J. Domb, Y. Ozaki, PLLA mesophase and its phase transition behavior in the PLLA−PEG−PLLA copolymer as revealed by infrared spectroscopy, Macromolecules 2010, 43, 4240–4246.
5 5. K. Wasanasuk, K. Tashiro, Structural regularization in the crystallization process from the glass or melt of poly(l‐lactic acid) viewed from the temperature‐dependent and time‐resolved measurements of FTIR and wide‐angle/small‐angle X‐ray scatterings, Macromolecules 2011, 44, 9650–9660.
6 6. J. Zhang, Y. Duan, H. Sato, H. Tsuji, I. Noda, S. Yan, Y. Ozaki, Crystal modifications and thermal behavior of poly(l‐lactic acid) revealed by infrared spectroscopy, Macromolecules 2005, 38, 8012–8021.
7 7. J. Zhang, K. Tashiro, A. J. Domb, H. Tsuji, Confirmation of disorder α form of poly(l‐lactic acid) by the X‐ray fiber pattern and polarized IR/Raman spectra measured for uniaxially‐oriented samples, Macromol Symp 2006, 242, 274–278.
8 8. J. Zhang, K. Tashiro, H. Tsuji, A. J. Domb, Disorder‐to‐order phase transition and multiple melting behavior of poly(l‐lactide) investigated by simultaneous measurements of WAXD and DSC, Macromolecules 2008, 41, 1352–1357.
9 9. K. Wasanasuk, K. Tashiro, Crystal structure and disorder in poly(l‐lactic acid) δ form (α′ form) and the phase transition mechanism to the ordered α form, Polymer 2011, 52, 6097–6109.
10 10. X. Chen, J. Kalish, S. L. Hsu, Structure evolution of α′‐phase poly(lactic acid), J. Polym. Sci. Part B Polym. Phys. 2011, 49, 1446–1454.
11 11. J. Kobayashi, T. Asahi, M. Ichiki, H. Oikawa, H. Suzuki, T. Watanabe, E. Fukada, Y. Shikinami, Structural and optical properties of poly lactic acids, J. Appl. Phys. 1995, 77, 2957–2973.
12 12. C. Aleman, B. Lotz, J. Puiggali, Crystal structure of the α‐form of poly (l‐lactide), Macromolecules 2001, 34, 4795–4801.
13 13. S. Sasaki, T. Asakura, Helix distortion and crystal structure of the α‐form of poly(l‐lactide), Macromolecules 2003, 36, 8385–8390.
14 14. K. Wasanasuk, K. Tashiro, M. Hanesaka, T. Ohhara, K. Kurihara, R. Kuroki, et al., Crystal structure analysis of poly(l‐lactic acid) α form on the basis of the 2‐dimensional wide‐angle synchrotron X‐ray and neutron diffraction measurements, Macromolecules 2011, 44, 6441–6452.
15 15. P. De Santis, J. Kovacs, Molecular conformation of poly (S‐lactic acid), Biopolymers 1968, 6, 299–306.
16 16. B. Eling, S. Gogolewski, A. J. Pennings. Biodegradable materials of poly(l‐lactic acid): 1. Melt‐spun and solution‐spun fibres, Polymer 1982, 23, 1587–1593.
17 17. W. Hoogsteen, A. Postema, Crystal structure, conformation and morphology of solution‐spun poly (l‐lactide) fibers, Macromolecules 1990, 23, 634–642.
18 18. J. Puiggali, Y. Ikada, H. Tsuji, L. Cartier, T. Okihara, B. Lotz, The frustrated structure of poly (l‐lactide), Polymer 2000, 41, 8921–8930.
19 19. K. Takahashi, D. Sawai, T. Yokoyama, T. Kanamoto, S. H. Hyon, Crystal transformation from the α‐ to the β‐form upon tensile drawing of poly(l‐lactic acid). Polymer 2004, 45, 4969–4976.
20 20. H. Wang, J. Zhang, K. Tashiro, Phase transition mechanism of poly(l‐lactic acid) among the α, δ and β forms on the basis of the reinvestigated crystal structure of the β form, Macromolecules 2017, 50, 3285–3300.
21 21. L. Cartier, T. Okihara, Y. Ikada, H. Tsuji, J. Puiggali, B. Lotz, Epitaxial crystallization and crystalline polymorphism of polylactides, Polymer 2000, 41, 8909–8919.
22 22. B. Lotz, G. Li, X. Chen, J. Puiggali, Crystal polymorphism of polylactides and poly(pro‐alt‐CO): The metastable beta and gamma phases. Formation of homochiral PLLA phases in the PLLA/PDLA blends, Polymer 2017, 115, 204–210.
23 23. H. Marubayashi, S. Asai, M. Sumita, Guest‐induced crystal‐to‐crystal transitions of poly(l‐lactide) complexes, J. Phys. Chem. B 2013, 117, 385–397.
24 24. H. Marubayashi, S. Asai, M. Sumita, Crystal structures of poly(l‐lactide)–CO2 complex and its emptied form, Polymer 2012, 53, 4262–4271.
25 25. H. Marubayashi, S. Asai, M. Sumita, Complex crystal formation of poly(l‐lactide) with solvent molecules, Macromolecules 2012, 45, 1384–1397.
26 26. H. Marubayashi, S. Akaishi, S. Akasaka, S. Asai, M. Sumita, Crystalline structure and morphology of poly(l‐lactide) formed under high‐pressure CO2, Macromolecules 2008, 41, 9192–9203.
27 27. Y. Ikada, K. Jamshidi, H. Tsuji, S. H. Hyon, Stereocomplex formation between enantiomeric poly(lactides), Macromolecules 1987, 20, 904–906.
28 28. T. Okihara, Lattice disorders in the stereocomplex and of poly(l‐lactide), Bull. Inst. Chem. Res. Kyoto Univ. 1988, 66, 271–282.
29 29. H. Tsuji, Y. Ikada, S. H. Hyon, Y. Kimura, T. Kitao, Stereocomplex formation between enantiomeric poly(lactic acid). VIII. Complex fibers spun from mixed solution of poly(d‐lactic acid) and poly(l‐lactic acid), J. Appl. Polym. Sci. 1994, 51, 337–344.
30 30. H. Tsuji, S. H. Hyon, Y. Ikada, Stereocomplex formation between enantiomeric poly (lactic acid)s. 4. Differential scanning calorimetric studies on precipitates