杜仲橡胶硫化胶交联密度与结晶性能关系研究

Study on Relationship between Cross-linking Density and Crystallization Characteristic of Gutta-Percha Rubber

采用差示扫描量热(DSC)法分析杜仲橡胶硫化胶交联密度对其物理性能和结晶性能的影响。结果表明:随着硫黄用量的增大,杜仲橡胶硫化胶的交联密度增大,邵尔A型硬度减小,100%定伸应力、拉伸强度和拉断伸长率先增大后减小;消除热历史后杜仲橡胶生胶的结晶特征减弱;随着交联密度的增大,硫化胶的DSC特征熔融峰减弱直至消失,结晶峰钝化,峰面积减小。

The effect of cross-linking density of gutta-percha rubber vulcanizate on its physical properties and crystallization characteristics was investigated by differential scanning calorimetry （DSC） method. The results showed that, as the addition level of sulfur increased, the cross-linking density of gutta-percha rubber vulcanizate increased, the Shore A hardness decreased,and the modulus at 100% elongation, tensile strength and elongation at break were increased at first and then decreased. After eliminating thermal history, the crystallization characteristic of gum rubber was weakened. When the cross-linking density increased,the melting peaks were weakened until they dis- appeared,the crystallization peaks became small and broad, and the area of crystallization peak de- creased.