纳米SiO2改性水性聚脲的制备与性能

Preparation and properties of nano-SiO2 modified waterborne polyurea

摘要:

采用纳米二氧化硅（SiO2）为改性剂，以异佛尔酮二异氰酸酯（IPDI）、聚醚胺（D2000）、二羟甲基丙酸（DMPA）、乙二胺（EDA）、3-氨丙基三乙氧基硅烷(KH550)以及三乙胺（TEA）为主要原料，通过溶胶凝胶法制备了纳米SiO2改性水性聚脲。利用FTIR、TEM、SEM、TGA等分别对聚合物结构与性能进行表征，并且研究了纳米SiO2含量对水性聚脲乳液和涂膜性能的影响。结果表明，随着纳米SiO2含量的增加，水性聚脲的粒径增大，黏度变大，涂膜的吸水率降低，拉伸强度先变大后变小，接触角变大和断裂伸长率降低。当体系中纳米SiO2质量分数为2%时，涂膜的综合性能最佳，吸水率和接触角分别为11.12%、75.24?；改性后的涂膜相比较未改性的涂膜热分解温度提高10℃左右。

Abstract:

Nano-SiO2 modified waterborne polyurea is prepared by sol-gel method，with isophorone diisocyanate (IPDI), polyether amine (D2000), dimethylolpropionic acid (DMPA), ethylenediamine (EDA), 3-aminopropyltriethoxysilane (KH550)and triethyl Amine (TEA) as the main raw material，nano-silica (SiO2) as modifier. The structure and properties of the polymer were characterized by FTIR, TEM, SEM and TGA, and the effects of nano-SiO2 content on the performance of waterborne polyurea emulsion and film were studied. The results show that the particle size of waterborne polyurea increased, the viscosity increased, the water absorption of the coating decreased, the tensile strength increased first and then de-creased, the contact angle increased and the elongation at break decreases, with the increase of nano-SiO2 content. When the mass fraction of nano-SiO2 was 2%, the comprehensive performance of the coating film was the best, the water absorption rate and the contact angle was respectively 11.12% and 75.24?; Compared with the unmodified coating film, thermal decomposition temperature of the modified coating film was increased by 10 ?C approximately.