摘要
采用γ-氨丙基三乙氧基硅烷(KH550)对高岭土进行表面改性,再将改性高岭土与异氰酸根封端的聚氨酯预聚体反应,制备含有无机粒子的高岭土改性水性聚氨酯乳液(WPU-K)。采用傅里叶变换红外光谱(FT-IR)对改性高岭土进行表征;使用粒度仪测定了WPU-K乳液粒径;通过扫描电镜(SEM)、透射电镜(TEM)、拉力机和热重分析分别对胶膜的表面形貌、力学性能和热学性能进行了表征。结果表明:随着改性高岭土质量分数的增加,乳液粒径变大、分布变宽,贮存稳定性下降,胶膜的热稳定性和硬度明显改善。当改性高岭土质量分数为8%时,与同组成聚氨酯相比,胶膜耐热性明显提高,拉伸强度增加22.6%,邵A硬度由53增加至82,吸水率减少73.5%。
The kaolin was modified by KH550, and then a polyurethane emulsion (WPU- K) was synthesized by reaction of the modified kaolin with the isoeyanate-terminated polyurethane prepolymer. The structure of the modified kaolin was characterized by Fourier transform infrared spectrometer (FT-IR). The particle size of WPU-K emulsion was determined by particle size analyzer. The morphology, mechanical properties and heat resistance of composite material (WPU-K) were observed via transmission electron microscopy (TEM), scanning e- lectron microscope (SEM), tensile tests and thermogravimetry (TG).The results indicated that, with increasing the mass fraction of modified kaolin, the particle size of WPU-K emul- sion was increased and the stability of emulsion was decreased, the hardness and the thermal stability of the films were improved obviously. When the mass fraction of modified kaolin was 8%, the cured film showed an improved thermal resistance as compared to pure polyurethane, furthermore, the tensile strength of the cured film was increased by 22.6%, the Shore A hardness was increased from 53 to 82, and the water absorption was reduced by 73.5%.
出处
《涂料工业》
CAS
CSCD
北大核心
2015年第2期28-34,共7页
Paint & Coatings Industry
关键词
改性高岭土
接枝
水性聚氨酯
modified kaolin
graft
waterborne polyurethane