不同支化程度丁腈橡胶性能的研究

通过对比结合丙烯腈含量和门尼粘度相近的3个牌号丁腈橡胶（NBR）的分子结构参数、加工性能和硫化胶性能，研究NBR支化程度对其性能的影响。结果表明：采用橡胶加工分析仪对生胶进行频率扫描、应变扫描、应力松弛3种方式分析得出了3种NBR的支化程度高低顺序；高支化程度NBR生胶和混炼胶的粘度对剪切速率敏感性强，混炼胶门尼粘度相对于生胶门尼粘度的增加值小，炭黑分散性高，硫化胶性能均一性好；低支化程度NBR生胶和混炼胶的粘度对温度敏感性强，硫化胶的拉伸强度、拉断伸长率较高，压缩永久变形小。;The influence of NBR branching degree on its properties was studied by comparing molecular structure parameter，processability and vulcanizate properties of three brands of NBR with similar bound acrylonitrile content and Mooney viscosity.The results showed that，the order of branching degree was obtained through the frequency scanning，strain scanning，stress relaxation analysis.For raw rubber and mixing compound of NBR with higher branching degree，the viscosity was more sensitive to shear rate during processing，the increase of Mooney viscosity of mixing compound relative to that of raw rubber was small，the carbon black dispersion and the homogeneity of vulcanizate performance were better.For raw rubber and mixing compound of NBR with low branching degree，the viscosity was more sensitive to temperature，the tensile strength，elongation at break and compression set of vulcanizates were better