硅酸铝-硅灰石复合粉体材料的制备及其在聚丙烯中的应用

Preparation of aluminium silicate-wollastonite composite powder and its application in PP

以硅灰石为原料,以硫酸铝和水玻璃为包覆剂,采用化学沉淀法,制备了一种纳米硅酸铝-硅灰石复合粉体材料;用氨基硅烷对该材料进行表面改性后填充聚丙烯制备了聚丙烯复合材料。采用SEM、BET氮吸附比表面积仪、粒度仪、白度仪、XRD、EDX、FTIR等测试方法对复合及表面改性粉体材料进行了表征,并探讨了氨基硅烷改性复合粉体的机制。结果表明:硅灰石表面均匀地包覆了一层纳米硅酸铝,白度由90.5提高到92.5,比表面积由1.41 m2/g提高到4.78 m2/g,晶粒平均尺寸为54 nm;填充PP质量分数40%的改性复合粉体可以使纯PP的拉伸强度由17.81 MPa提高到21.97 MPa,弯曲强度由23.72 MPa提高到39.20 MPa,热变形温度由65.7℃提高到94.3℃。

Taking wollastonite as raw material, aluminium sulfate and water glass as coating modifiers, a new type nano-aluminium silicate - wollastonite composite was obtained by the chemical depositing method. By modifying this composite powder with amino-silane and filling it in PP, the polypropylene composite was obtained. The composite and modified powder were characterized by SEM, BET, grain size analyser, whiteness apparatus, XRD, EDX and FTIR. The mechanism of composite powder modified by amino-silane was discussed. The results show that the surface of wollastonite is coated with nano-aluminum silicate evenly, the whiteness is increased from 90.5 to 92.5, the specific surface area is increased from 1.41 m^2/g to 4.78 m^2/g, and the average grain size of aluminium silicate is 54 nm. Filling 40 wt% modified composite powder in PP, the tensile strength, bending strength and heat distortion temperature of the material have been increased from 17. 81 MPa to 21. 97 MPa, from 23. 72 MPa to 39.20 MPa and from 65.7 ℃ to 94.3 ℃, respectively.