扩链剂对环氧聚氨酯复合乳液性能的影响

Effect of chain extender on properties of epoxy polyurethane hybrid emulsion

以甲苯二异氰酸酯(TDI-80)、聚醚二醇(N220)、三乙胺(TEA)为原料,1,4-丁二醇(BDO)、乙二胺(EDA)为小分子扩链剂,二羟甲基丙酸(DMPA)为亲水扩链剂,环氧树脂E-20为大分子扩链剂,合成了环氧聚氨酯复合乳液,讨论了几种扩链剂对合成的乳液性能的影响。结果表明,乳液的黏度、涂膜的硬度、拉伸强度随BDO、EDA、DMPA和E-20用量的增加而增大;乳液的外观和稳定性随BDO、EDA和E-20用量的增加变差,随DMPA的用量增加而变好;涂膜的吸水率随BDO和E-20用量的增加而减小,随EDA和DMPA用量增加先减小后增大。当BDO的添加量为6%、EDA为0.5%、DMPA为6%、E-20为5%～8%时,所制得的环氧聚氨酯复合乳液性能较好。

The epoxy polyurethane hybrid emulsion was prepared by using toluenediisocyanate （TDI）, polyether （N220） and triethylamine（TEA） as the materials, 1,4-butanediol（BDO） and ethylenediamine（EDA） as the micromolecule chain extender, dimethylolpropionic acid（DMPA） as the hydrophilic chain-extender, and epoxy resin as the macromolecules chain extender. The effect of several kinds of chain extender on the properties of the prepared emulsion were discussed. The experimental results showed that the viscosity of the emulsion and the hardness and mechanical property of the film were increased with increasing the amounts of BDO, EDA, DMPA and epoxy resiru The appearance and storage stability of the e- mulsion became poor with increasing the amount of BI）O, EDA and epoxy resin, while became better with increasing the a- mount of DMPA. The water absorption of the film was reduced with increasing the amount of BDO and epoxy resin,while decreased at first then increased with increasing the amount of EDA and DMPA. When the ratio of BDO was 6. 0%, the EDA was 0. 5%, the DMPA was 6.0%, and the epoxy resin was between 5.0%to 8.0%, the properties of the prepared e- mulsion and its film were excellent.