聚胺66在混合物中的结晶与随机非结晶的聚乙烯异甲胺- (hexamethylene isophthalamide-co-terephthalamide) 的结晶
Xiaoshi Zhang1, John Buzinkai2, René Androsch3
1School of Engineering, Penn State Behrend, Erie, Pennsylvania 16563, United States.
将一种非结晶的聚合物添加到聚胺66 (PA 66) 中,会改变其结晶动力学和相位选择. 核化机制,而不仅仅是动力学,在低温下决定了晶体相位的形成.
科学领域:
- 聚合物科学 聚合物科学
- 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:
- 聚合物通常表现出双模结晶动力学,具有明显的低温和高温模式.
- 这些模式与不同的核化机制和晶体多态联系在一起.
- 了解这些动力学的调制对于聚合物加工和材料性能至关重要.
研究的目的:
- 为了研究将随机的非结晶的聚乙烯异甲胺-共甲胺 (PA 6I/6T) 纳入聚胺66 (PA 66) 结晶动力学的影响.
- 阐明PA 66/PA 6I/6T混合物中控制相选择和结晶行为的基本机制.
- 探索无形元件对聚合物混合阶段行为在广泛的温度范围内的影响.
主要方法:
- 系统地将PA 6I/6T添加到PA 66中以创建混合物.
- 快速扫描热度计 (FSC) 用于分析结晶动力学和相变.
- 补充分析技术,以全面描述混合物的行为.
主要成果:
- 添加PA 6I/6T系统地减缓了PA 66的结晶.
- 从双模转变为单模动力学的转变在30重%以上的PA 6I/6T上观察到.
- 低温下的中相形成是由核化机制 (异质到同质) 的切换决定的,而不是整体动力学.
- 在所有混合物中,单个玻璃过渡温度 (Tg) 证实了分子水平的混合性.
- 结晶后Tg上升的变化表明PA 6I/6T在无形阶段的丰富.
结论:
- 核化机制,而不仅仅是结晶动力学,在深度低温下控制着多态体的选择.
- 无形成分 (PA 6I/6T) 影响PA 66混合物的结晶动力学,多态选择和相位行为.
- 结果提供了对聚合物混合阶段行为和结晶控制的基本见解.
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