稀释对基于的稀土聚乙烯的结晶动力学的稀释的影响
Xiaohu Zhang1, Xiaofan Li1, Wenbin Zhu1
1Huangpu Institute of Materials, Centers for Aircraft Science, Guangzhou 510700, China.
Polymers
|January 11, 2024
概括
经过处理的蒸芳香提取物 (TDAE) 油和聚乙烯-异烯共聚合物 (BIR) 抑制了基于新的稀土聚乙烯 (Nd-BR) 结晶. TDAE油会影响结晶率,而BIR会抑制核形成,从而影响材料的性能.
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
- 技术 技术 技术
背景情况:
- 基于的稀土聚乙烯 (Nd-BR) 是轮胎制造中的一个关键材料.
- 了解其结晶行为对于优化性能和处理至关重要.
- 像TDAE油和BIR这样的添加剂可以显著改变聚合物结晶.
研究的目的:
- 研究TDAE油和BIR对Nd-BR结晶的抑制作用.
- 阐明TDAE和BIR在修改结晶动力学中的不同作用.
- 建立添加剂度,结晶温度和激活能量之间的相关性.
主要方法:
- 差分扫描热量计 (DSC) 用于研究结晶和融化行为.
- 分析结晶温度 (Tc),点 (Tm) 和度变化.
- 确定Avrami指数 (n) 的异热结晶动力学.
- 结晶激活能量的计算.
主要成果:
- 无论是TDAE还是BIR都显著降低了Nd-BR的Tc,Tm和变化.
- TDAE油主要影响结晶率,而BIR主要抑制核化.
- 在高TDAE (40 PHR) 或BIR (60 wt.%) 度下发生不完全结晶,导致冷结晶.
- 对于Nd-BR的Avrami指数 (n) 通常为2.5-3.0;TDAE在低度下降n,BIR在60重%.
- 在低添加剂度和T> -50°C时观察到负激活能量,表明结晶率下降.
- 在60重%BIR和-50°C
结论:
- TDAE 油和 BIR 作为 Nd-BR 的有效结晶抑制剂.
- 在TDAE和BIR之间做出选择取决于结晶动力学所需的修改 (速率与核化).
- 了解这些相互作用对于为特定应用,特别是轮胎化合物量身定制-的特性至关重要.
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