纳米TiO_2/玻璃纤维复合增强体的制备及表征

Preparation and characterization of nano-TiO_2/glass fiber composite powders

利用植酸对短玻璃纤维粉进行预处理,然后以钛酸丁酯为原料,乙醇介质中通过胶溶-水解法在玻璃纤维表面制备了纳米TiO2。SEM观察表明直接在玻璃纤维表面进行制备难以形成有效包覆,而植酸处理有利于TiO2均匀包覆,纤维表面TiO2颗粒尺寸约50nm,呈多孔结构。XPS结果显示纳米TiO2/玻璃纤维复合粉体表面Ti元素处于TiO2中Ti 4+结合态,同时存在Ti—O—Si键。分析粉体的XRD结果认为纳米TiO2主要以锐钛矿形式存在,热分析结果表明复合粉体在受热过程中失重约6.3%,相应DTA曲线中未出现明显吸热峰。对比了原始玻璃纤维粉和纳米TiO2/玻璃纤维复合粉体在环氧树脂中分散状态及相应复合材料涂层的耐磨失重,SEM观察表明未处理玻璃纤维难以与树脂形成有效的界面粘结,而经过改性后,复合颗粒与基体结合紧密,纳米TiO2表面的羟基参与环氧树脂的固化过程,显著改善了两相之间的界面作用,改性后填充体系的耐磨失重降低63.6%。

Short glass fiber powders were firstly treated by phytic acid,and then coated by nano TiO2 in alcohol solution of Ti（OBu）4 through peptization-hydrolyzation method.SEM observation showed that it was difficult to directly coat glass fiber with TiO2 particles without phytic acid treatment,but after treated by phytic acid nano TiO2 particles approximate 50 nm in size were uniformly coated the surface of glass fiber forming porous film.The results of XPS showed that Ti elements on the surface of the composites were in the state of Ti4＋ of TiO2 ,and there also existed Ti-O-Si bonds.XRD analysis revealed that nano TiO2 mainly existed as anatase form.Thermal analysis showed that the weight loss of the composite powders was about 6.3% during the heat-ing process,and no obvious endothermic peak appeared in the DTA curve.The dispersion state and the abrasive loss of the epoxy resin filled with original glass fibers and the composite powders were compared.SEM observa-tion showed that the untreated glass fiber failed to form an effective bonding interface with epoxy resin.Howev-er,nano-TiO2/glass fiber composite powders were closely bonded with the resin due to the reaction of Ti-OH and epoxy resin during the curing process.The abrasive loss of composite coatings filled with nano-TiO2/glass fibers was decreased by 63.6%.