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对多态乳酸的多态特异晶度的定量DSC评估以及自组装核剂和PEG可塑剂的影响

Maarten Colaers¹, Wim Thielemans², Bart Goderis¹

¹Department of Chemistry, Polymer Chemistry and Materials, KU Leuven, Celestijnenlaan 200F-Box 2404, 3001 Heverlee, Belgium.

|May 14, 2025

概括

这项研究详细介绍了像BHAD这样的核化剂和像PEG这样的增塑剂如何影响聚乳酸 (PLA) 结晶性. BHAD促进了特定的晶体形式 (α) 并增强了整体结晶性,特别是PEG,以改善材料性能.

科学领域:

聚合物科学与工程聚合物科学与工程
材料科学材料科学材料科学
结晶运动学结晶运动学

背景情况:

聚乳酸 (PLA) 是一种广泛使用的可生物降解聚合物,其特性高度依赖于其晶体结构.
控制PLA晶度对于为各种应用量身定制其机械和热性能至关重要.
众所周知,核剂和可塑剂会影响聚合物结晶,但它们对PLA多态的特定影响需要详细调查.

研究的目的:

在不同的条件下,研究聚乳酸 (PLA) 的温度分辨率,多态特异性结晶性.
评价N,N-bis() 六氧化二化 (BHAD) 作为核化剂和PEG 1000作为塑化剂对PLA结晶的影响.
为了准确量化PLA晶度,使用来自差分扫描热量计 (DSC) 的温度依赖,多态特异的过渡度.

主要方法:

差分扫描热量计 (DSC) 用于测量温度依赖的过渡度,以准确计算结晶度.
使用广角X射线衍射 (WAXD) 独立证实了PLA的多态结构.
实验对半晶体 (PLA-1) 和无形 (PLA-2) PLA等级进行了实验,在冷却和加热10°C/分钟时,BHAD和PEG 1000的度各不相同.

主要成果:

纯PLA-1在冷却时表现出2%的α'结晶性,在加热时通过冷结晶增加到38%.
添加BHAD (≥0.4%) 促进了α结晶体在α'上形成,在冷却过程中达到38%的结晶度.
在PLA-1中,10%重量的PEG在冷却过程中导致了初级α结晶,在加热后导致了二次的球体内α'结晶 (共34%).
观察到1重%的BHAD和10重%的PEG具有协同效应,使结晶温度增加40°C,并将α结晶度提高到44%.

结论:

精确确定PLA结晶性需要温度依赖的,多态特异的过渡度从DSC,通过WAXD验证.
BHAD有效地作为核化剂,促进α结晶并增加整体结晶性,特别是在较高度下.
PEG和BHAD的组合显示出显著的协同效应,增强了PLA的结晶动力学和可实现的结晶性.

关键词:

美国国家安全委员会 DSC.结晶的行为结晶的行为核化剂是一种核化剂.塑化剂是一种可塑化剂.聚乳酸) 是一种乳酸.

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