硅烷偶联剂KH570改性TiO2超疏水滤料的制备与性能

通过溶胶-凝胶法以钛酸四丁酯为前驱体，醋酸为催化剂制备TiO₂溶胶，利用γ-甲基丙烯酰氧基丙基三甲氧基硅烷（KH570）对其进行低表面能修饰，得到疏水改性的TiO₂溶胶，然后喷涂到滤料表面使其具有超疏水性。对改性前后滤料的润湿性、表面形貌、化学成分和过滤性能进行分析。结果表明：改性涂层均匀沉积在滤料表面，将纤维表面完整包裹，改性后滤料的水接触角达156.29°。在过滤风速为0.043~0.127 m/s时对粒径为0.3 μm的颗粒进行过滤性能测试，改性后滤料的过滤效率比未改性滤料平均增加2.7672%，过滤品质因数增加0.34%，提高了滤料的过滤性能。此外，在经50次砂纸磨损循环和30 h酸碱溶液浸泡后，疏水滤料仍具有超疏水性。通过清洁煤粉污染的表面发现改性滤料具有优异的自清洁性能。

Preparation and properties of TiO2 superhydrophobic filter media modified by silane coupling agent KH570

TiO₂ sol was prepared by sol-gel method using tetrabutyl titanate as precursor and acetic acid as catalyst,and then hydrophobically modified TiO₂ sol was obtained by reducing its surface energy withγ-methacryloxypropyl trimethoxysilane(KH570),the modified TiO₂ sol was sprayed on the surface of the filter media to make it superhydrophobic.The wettability,surface morphology,chemical composition and filtration performance of the filter media before and after modification were analyzed.The results show that the modified coating is uniformly deposited on the surface of the filter media and the fiber surface completely wrapped,and the water contact angle of the modified filter media reaches 156.29°.By testing the filtration performance of the particles with the size of 0.3μm at the filtration velocity of 0.043-0.127 m/s,it can be seen that the filtration efficiency of the modified filter media is increased by an average of 2.7672%compared with the unmodified filter media,and the filter quality factor is increased by 0.34%,which improves the filtration performance of the filter media.In addition,the hydrophobic filter media still has superhydrophobicity after 50 times of sandpaper abrasion cycles and 30 h acid-base solution immersion.The modified filter media has excellent self-cleaning performance by cleaning the surface of coal powder pollution.