TY - JOUR
T1 - Crystal polymorphism of polylactide and its composites by X-ray diffraction study
AU - Hsieh, Ya Ting
AU - Nozaki, Shuhei
AU - Kido, Makoto
AU - Kamitani, Kazutaka
AU - Kojio, Ken
AU - Takahara, Atsushi
N1 - Funding Information:
Acknowledgements The financial support for this work was provided by JSPS Grant-in-aid for Scientific Research (A) (Research Project Number: 26248053, 17H01221). The synchrotron radiation X-ray diffraction experiments were performed at the BL02B2 of SPring-8 with the approval of the Japan Synchrotron Radiation Research Institute (JASRI) (Proposal No. 2014B1285 and Proposal No. 2015B1541). Part of this work was supported by the Cabinet Office, Government of Japan, Cross-ministerial Strategic Innovation Promotion Program (SIP), “Technologies for Smart Bio-industry and Agriculture” (funding agency: Bio-oriented Technology Research Advancement Institution, NARO).
Publisher Copyright:
© 2020, The Society of Polymer Science, Japan.
PY - 2020/7/1
Y1 - 2020/7/1
N2 - Polylactide (PLA) exhibits various types of crystal modifications depending on the preparation conditions, including the components. To solve the open question, a reliable calculation method for crystallinity, crystal forms, and composition in neat PLA and PLA composites was developed on the basis of temperature-dependent synchrotron wide-angle X-ray diffraction results. The relative composition of amorphous, α-form, and α’-form phases of PLA and its composites filled with halloysite nanotubes during heating was successfully obtained. It was found that only 47–56% of α’-form crystals transform into α-form crystals during a 2 °C/min heating process for PLA with a molecular weight of 54,300 g/mol. The loading of halloysite nanotubes decreases the cold crystallization and starting transition (α’ crystals transform into α-form crystals) temperatures of PLA. The crystallinity and the main diffraction peak intensity as a function of temperature were also analyzed. These results suggest that the α’-to-α form transition is a solid-solid phase transition.
AB - Polylactide (PLA) exhibits various types of crystal modifications depending on the preparation conditions, including the components. To solve the open question, a reliable calculation method for crystallinity, crystal forms, and composition in neat PLA and PLA composites was developed on the basis of temperature-dependent synchrotron wide-angle X-ray diffraction results. The relative composition of amorphous, α-form, and α’-form phases of PLA and its composites filled with halloysite nanotubes during heating was successfully obtained. It was found that only 47–56% of α’-form crystals transform into α-form crystals during a 2 °C/min heating process for PLA with a molecular weight of 54,300 g/mol. The loading of halloysite nanotubes decreases the cold crystallization and starting transition (α’ crystals transform into α-form crystals) temperatures of PLA. The crystallinity and the main diffraction peak intensity as a function of temperature were also analyzed. These results suggest that the α’-to-α form transition is a solid-solid phase transition.
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U2 - 10.1038/s41428-020-0343-8
DO - 10.1038/s41428-020-0343-8
M3 - Article
AN - SCOPUS:85084067370
VL - 52
SP - 755
EP - 763
JO - Polymer Journal
JF - Polymer Journal
SN - 0032-3896
IS - 7
ER -