异氰酸酯种类对PCL型聚氨酯混炼胶性能影响

Effect of Isocyanate Type on Properties of PCL MPUR

以聚己内酯二醇、不同种类异氰酸酯及扩链剂α-烯丙基甘油醚等为原料,采用预聚体法工艺合成混炼型聚氨酯弹性体(MPUR)生胶,与各种橡胶助剂配合,采用橡胶加工方法进行混炼硫化。通过改变MPUR中的异氰酸酯种类,探究硬段结构对MPUR力学性能、玻璃化转变温度(Tg)、耐老化性能和阻尼性能的影响。结果表明,MPUR在特定温度区间的Tg主要由软段结构所决定;力学性能受MPUR硫化后的交联密度影响,化学交联密度大,力学性能优;分子链规整性好,损耗正切小。

A millable polyurethane elastomer rubber(MPUR)was synthesized using polycaprolactone glycol,different isocyanates and the chain extenderα-allyl glyceroether as raw materials by prepolymerization method.It was mixed and vulcanized with various rubber additives using rubber processing methods.By changing the types of isocyanates in MPUR,the effects of hard segment structure on the mechanical properties,glass transition temperature,aging resistance and damping performance of MPUR was investigated.The results indicated that the Tg of MPUR in a specific temperature range was mainly determined by the soft segment structure.The mechanical properties were affected by the crosslinking density of MPUR after vulcanization.The chemical crosslinking density was high and the mechanical properties were excellent.The molecular chain regularity was good,the loss tangent was small.