PU改性TDE-85/ MeTHPA环氧体系的显微形貌特征研究

本实验选用聚醚二元醇、甲苯二异氰酸酯（TDI）作为原料，合成了聚醚型聚氨酯预聚体。采用该预聚体扩链剂1，4-丁二醇（1，4-BDO）、交联剂三羟甲基丙烷（TMP）对TDE-85／甲基四氢苯酐（MeTHPA）环氧树脂体系行改性。利用扫描电镜分析，探讨了聚氨酯（PU）改性TDE-85／甲基四氢苯酐（MeTHPA）环氧树脂体系结构特征。结果表明，当合成PＵ预聚体的PPG相对分子质量不同时，改性环氧树脂体系的表面形貌随聚氨酯预聚体加入量的变趋势是相同的。当聚氨酯含量较小时，呈明显的“海岛”结构。随着聚氨酯加入量增多到一定量时，两网络互穿程度高，相分离程度不明显，具有互穿网络聚合物结构特征。随着聚氨酯含量的继续增多，相区尺寸明显增大，两相相容变差，相界面变得较清晰。

SEM Image of Polyurethane Modified TDE-85/MeTHPA Epoxy Resin

The title TDE-85/MeTHPA epoxy resin system modified by polyurethane was prepared with polyurethane prepolymer(formulated by PPG and TDI),chain-extended reagent(1,4-BDO) and crosslink agent(TMP).The structure of the system were characterized by SEM.Results indicated that the morphology variation trend with the PU prepolymer contents are same in this modified system,though the two kinds of PPG molecular weight are different.When the PU content was low,the system showed "Island" structure,and higher PU content gave higher degree of interpenetrating network,but unconspicuous phase separation.Significant high PU content will give conspicuous phase separation,large size of phases and poor compatibility.