Accelerated crystallization of poly(L‐lactide) by physical aging
Accelerated crystallization of poly(L‐lactide) by physical aging
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DOI：
10.1002/app.31667
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发表时间：
2009-12
影响因子：
3
通讯作者：
H. Tsuji;M. Sawada
中科院分区：
文献类型：
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作者：
H. Tsuji;M. Sawada
对非晶聚l -丙交酯（PLLA）在低于玻璃化转变温度（Tg） 25-50℃下进行了90天的低温物理时效。无论时效温度如何，物理时效均显著提高了Tg和玻璃化转变焓，但未引起结晶。PLLA在加热过程中的非等温结晶仅通过50℃的物理时效来加速。结果表明，仅在50℃物理时效形成的结构在加热过程中促进了PLLA的加速结晶，而在25℃和37℃物理时效形成的结构在加热过程中对PLLA结晶的影响可以忽略不计，除非37℃物理时效持续长达90天。讨论了物理时效加速PLLA结晶的机理。©2009 Wiley期刊公司高分子学报，2010
The low-temperature physical aging of amorphous poly(L-lactide) (PLLA) at 25–50°C below glass transition temperature (Tg) was carried out for 90 days. The physical aging significantly increased the Tg and glass transition enthalpy, but did not cause crystallization, regardless of aging temperature. The nonisothermal crystallization of PLLA during heating was accelerated only by physical aging at 50°C. These results indicate that the structure formed by physical aging only at 50°C induced the accelerated crystallization of PLLA during heating, whereas the structure formed by physical aging at 25 and 37°C had a negligible effect on the crystallization of PLLA during heating, except when the physical aging at 37°C was continued for the period as long as 90 days. The mechanism for the accelerated crystallization of PLLA by physical aging is discussed. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010