通过限制冷结晶,制造具有高膨胀率和定向细胞结构的聚乳酸泡
Kesong Yu1, Dong Wang1, Junji Hou1
1School of Materials Science and Engineering, Zhengzhou University, Zhengzhou 450001, China.
International journal of biological macromolecules
|August 26, 2023
概括
通过较短的二氧化碳浸泡时间限制在聚乳酸 (PLA) 中的冷结晶,使高膨胀PLA泡成为可能. 这种方法保留了无形区域,从而使泡在包装和建筑中具有优越的泡特性.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物科学 聚合物科学
- 泡技术技术的使用
背景情况:
- 半晶聚合物泡与结晶行为密切相关.
- 在聚乳酸 (PLA) 泡中达到高膨胀率需要控制其冷结晶.
- 二氧化碳 (CO2) 作为聚合物的塑化剂和泡剂.
研究的目的:
- 为了研究二氧化碳浸泡时间对PLA冷结晶的影响.
- 通过限制冷结晶来制造高膨胀PLA泡.
- 评估由此产生的PLA泡的细胞结构和特性.
主要方法:
- 聚乳酸 (PLA) 用超临界CO2进行泡.
- 在10MPa下使用了不同的CO2浸泡时间 (例如3分钟与40分钟).
- 进行了动态机械分析 (DMA) 和晶体形态分析.
- 发泡实验是在不同温度 (90-115°C) 的范围内进行的.
主要成果:
- 在10MPa的浸泡时间为40分钟,导致PLA的冷结晶完成.
- 短3分钟的浸泡时间有效地限制了PLA冷结晶.
- 在广泛的温度范围 (90-115°C) 中,通过3分钟的浸泡时间实现了高扩张比 (>10).
- PLA泡表现出一个定向的细胞结构,而异型泡显示出增强的压力强度和耐热性.
结论:
- 通过短CO2浸泡时间限制冷结晶对于生产高膨胀PLA泡至关重要.
- 二氧化碳的塑化效应在低温和高温下不同影响PLA结晶.
- 异构型PLA泡中的定向细胞结构赋予了改进的机械和热性能.
- 这些PLA泡显示出在缓冲,包装和建筑领域应用的巨大潜力.
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