目的研究封端剂γ-氨丙基三乙氧基硅烷(KH550)和丙烯酸羟乙酯(HEA)对聚氨酯分散液(WPU)性能的影响。方法采用预聚体法合成聚氨酯分散液,通过傅里叶红外光谱(FTIR)对改性聚氨酯特征官能团进行表征,探讨KH550和HEA用量对聚氨酯分散液粒径大小与分布、表面张力、黏度以及附着力的影响。结果 WPU的粒径随着KH550用量的增加而逐渐增大,且分布变宽,黏度变小;KH550的引入降低了分散液的表面张力;HEA的引入对表面张力的影响较小,WPU的粒径随着HEA用量的增大而逐渐变小,且分布变窄,黏度变大。2种封端剂改性后分散液在PA、PET包装薄膜上表现出了良好的附着力。结论 KH550的引入能够提升水性聚氨酯在薄膜上的附着力,调节分散液黏度。
This paper studied the influence of end-capping reagents including 3-triethoxysilylpropylamine(KH550)and hydroxyethyl acrylate(HEA) on the properties of polyurethane dispersions(WPU). Polyurethane dispersions were prepared by pre-polymer method and the structure of polyurethane backbone was characterized by FTIR. The influences of the dosage of KH550 and HEA on particle size and distribution, surface tension, viscosity and adhesion of dispersions were investigated. The particle size and distribution of WPU were increased with increase of the dosage of KH550 but the viscosity decreased. The introduction of KH550 deduced the surface tension obviously but HEA had a little influence on the surface tension. With increase of the dosage of HEA, the particle size and distribution of WPU decreased but the viscosity increased. The adhesion of the two modified end-capping reagents on the PA and PET packaging film was excellent. The introduction of KH550 can improve the adhesion of WPU on films and adjust the viscosity of dispersions.