氟硅改性无溶剂聚氨酯涂层的制备及性能研究

Preparation and Property of Fluorine-Silicone Modified Solvent-Free Polyurethane Coating

借助硅氢加成反应将丙烯酸六氟丁酯接枝于含氢硅油侧链,合成了一种氟硅改性剂,并将其用于无溶剂双组分聚氨酯的改性。首先对改性剂的合成工艺进行了优化,然后对其改性后聚氨酯涂层的表面形貌、疏水性及耐磨性进行了研究。结果表明:合成改性剂的最佳反应温度120℃、时间12 h、催化剂用量30 mg/kg,在此条件下接枝率可高达89%;表面形貌及元素分析表明,氟、硅元素在聚氨酯中分散性良好;随着PSF添加量的增加,涂层表面粗糙度和水接触角均呈增大趋势,当PSF添加量为7.5%时,涂层表面水接触角可达118.3°;耐磨测试表明,随PSF添加量增大,涂层耐磨性先提升后下降,添加量为2.5%时,耐磨性最佳。

A kind of fluorine-silicone modifier(PSF)was synthesized by grafting hexafluorobutyl acrylate onto polydimethylhydrosiloxane via hydrosilylation reaction,and then used for the modification of solvent-free two-component polyurethane.The synthesis process of the modifier was optimized,and the surface morphology,hydrophobicity and abrasion resistance of the PSF modified polyurethane coatings were investigated.Results showed that the optimum reaction temperature,time and catalyst loading were 120℃,12 h and 30 mg/kg,respectively.In this condition,the grafting ratio could reach 89%.Results of surface morphology and elemental analysis showed that the fluorine and silicon elements were well dispersed in the polyurethane coating.The surface roughness and water contact angle(WCA)of the coating exhibited an obvious increase with the addition of PSF.When the PSF loading was 7.5%,the coating’s WCA could reach 118.3°.Results of abrasion resistance test presented that the coating’s abrasion resistance first increased and then decreased with the increase of PSF content,and the best abrasion resistance was achieved with the PSF loading of 2.5%.