烯烃自复分解反应对氢化丁腈橡胶相对分子质量的调控

Molecular Weight Regulation of Hydrogenated Nitrile Rubber Through Self-Metathesis

利用凝胶渗透色谱技术研究了双键含量、催化剂用量及溶液浓度对氢化丁腈橡胶(HNBR)烯烃自复分解反应的影响。结果表明,双键含量高的HNBR更容易进行复分解反应;HNBR溶液质量分数为9%时,催化剂用量高于0.2phr才能使双键摩尔分数为20%的HNBR发生有效的复分解反应。适当提高HNBR的溶液浓度,也可提高HNBR的复分解反应效率。复分解降解后HNBR的门尼黏度降为原来的一半时,硫化胶的物理力学性能保持良好,拉伸强度、100%定伸应力、撕裂强度分别为改性前的70%、75%和94%。

The influences of double bonds content, loading of Zhan 1-B catalyst, and the polymer solution concentration on self-metathesis reaction of HNBR, by which molecular weight of （H）NBR was regulated, were investigated by GPC. The results show that it is more difficult for hydrogenated nitrile rubber （HNBR） with less double bond content to be self-metathesized than HNBR with higher double bond content or nitrile rubber （NBR）. For 9 % HNBR with 20 % residual double bond, more than 0.2 phr of Zhan 1-B catalyst is necessary for efficient metathetic degradation. Appropriately increasing rubber concentration is helpful to improve the catalyst efficiency Tensile strength, 100% modulus and tear strength of metathesized HNBR with half Mooney viscosity, are 70% 75 % and 94 % of that of origin HNBR, respectively.