硬链段浓度对RIM交联聚氨酯结构和性能的影响

Effect of Content of Hard Segment on Structures and Properties of RIM Crossl inking Polyurethanes

用l-MDI/1,4-BDO/PPO-EO快反应体系,考察硬段浓度对聚氨酯结构与性能的影响。发现样品的交联度、模量和抗张强度随硬段浓度增加而提高,交联趋向均匀,断裂伸长率在浓度30％处出现最大值。ATR-FTIR和DSC分析表明,微相分离程度随硬段浓度增大而降低。

The effect of content of hard segment on the structure and properties of RIM crosslinking polyurethane(l-MDI/l , 4-BDO/PPO-EO) has been studied. The results of equilibrium swelling, ATR-FTIR and DSC show that increasing the content of hard segment increases the degree of linkage ,and decreases the degree of microphase separation and ordering in the hard rich domains. By TEM, the phase separation phenomena on different levels, namely, macrophase separation and microphase separation were observed.