在不同条件下通过拉伸制备的PLA板的表征:再加工和建立最佳条件的影响
Zaida Ortega1, Paula Douglas2, Paul R Hanna2
1Departamento de Ingeniería de Procesos, Universidad de Las Palmas de Gran Canaria, 35017 Las Palmas de Gran Canaria, Spain.
Materials (Basel, Switzerland)
|July 29, 2023
概括
这项研究优化了聚酸 (PLA) 薄膜的双轴拉伸,发现82°C是增强机械性能的最佳温度. 拉伸式PLA薄膜表现出强大的性能,无论先前的加工,展示了薄,强大的生物材料的潜力.
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
- 生物材料工程 生物材料工程
背景情况:
- 聚酸 (PLA) 是包装和一次性产品中广泛使用的生物材料.
- 关于PLA的拉伸行为存在有限的研究,特别是在各种加工条件下.
- 了解PLA对拉伸的反应对于优化其应用至关重要.
研究的目的:
- 研究注塑PLA双轴拉伸的最佳条件.注塑PLA的双轴拉伸的最佳条件.
- 评估预处理 (包括模拟回收) 对PLA伸展行为和最终性能的影响.
- 为了确定拉伸参数 (温度,时间,拉伸率,拉伸比率) 对薄膜特性的影响.
主要方法:
- 在各种条件下 (压力,干燥,挤出前处理) 进行注射成型的PLA样本.
- 描述包括机械,热,热机械,吸水和结晶动力学分析.
- 双轴拉伸是在受控的温度,时间,应变速率和拉伸比率条件下进行的.
主要成果:
- 挤出预处理导致热降解,降低了热稳定性,粘度和机械性能.
- 双轴拉伸的PLA薄膜表现出不变的机械性能,不论前处理方法如何.
- 最佳拉伸温度被确定为82°C,产生更高的强度.
- 增加的拉伸比增加了弹性模量和不透明性,这是由于应力诱导的结晶性.
- 生产了50微米薄的薄膜,具有出色的机械性能 (90MPa的产量,4000MPa的断裂强度/模块).
结论:
- 双轴拉伸可以显著提高PLA膜的性能,实现高强度和薄度.
- 82°C的最佳拉伸温度对于最大限度地提高产量和断裂强度至关重要.
- 在拉伸后,即使在模拟回收后,PLA膜也在机械性能方面表现出弹性.
- 这项研究为生产高级应用的高性能薄PLA薄膜提供了途径.
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