天然橡胶低温结晶性能分析

天然橡胶作为一种绿色的自补强高分子材料,有着合成橡胶无法比拟的优点。已有大量关于天然橡胶应变诱导结晶研究的文献报道,而对天然橡胶低温结晶研究的文献报道较少,天然橡胶低温结晶的研究对耐低温天然橡胶制品的生产有着理论指导意义。本文采用差示扫描量热法(DSC)和广角X射线衍射(WAXD)研究了天然橡胶的低温结晶结晶度及晶粒尺寸。研究结果表明,天然橡胶低温结晶时出现两种结晶类型,其结晶度随着结晶时间的延长而增加,在5 h左右结晶完全;天然橡胶的结晶度和晶粒尺寸没有发生变化。表明天然橡胶低温结晶结晶度的增加来源于晶粒尺寸的增长而不是晶粒数量的增加。

Analysis of Low Temperature Crystallization Properties of Natural Rubber

As a green self-reinforcing polymer material, natural rubber has the advantage that synthetic rubber can t match. There have been a lot of literature reports on strain-induced crystallization of natural rubber, but there are few reports on the research of low-temperature crystallization of natural rubber. The research on low-temperature crystallization of natural rubber has theoretical guiding significance for the production of low-temperature resistant natural rubber products. In this paper, the low temperature crystallinity and grain size of natural rubber were studied by differential scanning calorimetry (DSC) and wide-angle X-ray diffraction (WAXD). The results show that there are two kinds of crystals when natural rubber is crystallized at low temperature. The crystallinity increases with the crystallization time, and it crystallizes completely at about 5 h. The crystallinity and grain size of natural rubber do not change. It indicates that the increase in the crystallinity of low-temperature crystallinity of natural rubber is derived from the increase in grain size rather than the increase in the number of grains.