正硅酸乙酯为无机组分前驱体的聚碳酸酯耐磨涂层

Hybrid coatings with tetraethoxysilane as the inorganic network precursor on polycarbonate for improvement of abrasion resistance

以正硅酸乙酯(TEOS)作为无机组分的前驱体,甲基三甲氧基硅烷(MTMS)水解聚合产物作为有机组分,通过溶胶-凝胶法在聚碳酸酯(PC)表面形成耐磨涂层。红外光谱分析表明该涂层具有Si—O—Si的交联网络结构。研究了MTMS和TEOS的摩尔比对涂层的光学性能、硬度、附着力和耐磨性能的影响。结果表明,当MTMS和TEOS的摩尔比为2∶1时,涂层的综合性能达到最优,该涂层在经历500次耐磨试验后的雾度为12.69%,而纯PC的雾度增至42.38%。采用SEM和TEM分析了MTMS/TEOS具有优异耐磨性能的原因在于该涂层具有纳米SiO2粒子分散于有机基体的微观结构。

The hybrid coatings were synthesized through the sol-gel process using MTMS as organic pnase, tetraethoxysilane （TEOS） as the inorganic network precursor and deposited on polycarbonate for improvement of abrasion resistance. FT-IR showed that the cross linked network structure of Si--O--Si formed due to the hy- drolysis-condensation reactions of alkoxy groups in the MTMS/ TEOS sol. The influence of the mole ratios of MTMS and TEOS on the optical properties, pencil hardness, adhesion properties and the abrasion resistance of the coatings were investigated. The result indicate that the MTMS/ TEOS coating possess the best properties when the original molar ratio of MTMS and TEOS is 2 ： 1. After 500 wear cycles during an abrasion test, the haze of PC coated with the hybrid coating derived from the optimized component was only 12.69%, while that of uncoated PC rose up to 42.38%. Scanning electron microscope （SEM） and transmission electron microscope （TEM） were used to determine the microstructure of the MTMS/ TEOS coating and the micrographs revealed the homogeneous dispersion of nanosilica particles in the polymeric matrix.