硅灰石表面包覆二氧化硅复合颗粒制备与表征

发布时间：2018-01-31 15:28

本文关键词： 二氧化硅硅灰石复合颗粒微观形态复合机理　出处：《辽宁科技大学》2015年硕士论文　论文类型：学位论文

【摘要】：颗粒的复合化是构建新物质的重要途径,还可以通过颗粒复合来促进颗粒功能化,制备出的新物质可以改变单一颗粒的表面性质,提高颗粒的分散性、流动性等性能。二氧化硅具有优异的物理化学性能,在塑料、橡胶等工业领域上有广泛的应用范围。将无定型二氧化硅颗粒或膜包覆在硅灰石表面制备出二者的复合颗粒,即可发挥二氧化硅颗粒的补强功能,又可消除硅灰石颗粒的棱角、导致其表面粗糙,从而解决硅灰石与基体相容差等问题。本论文采用机械力化学法,通过二氧化硅颗粒的解聚分散、硅灰石的分散和二者湿法研磨方式复合等工序制备出二氧化硅/硅灰石复合颗粒,对制备过程中的影响因素进行了考察和优化,研究了制备复合颗粒材料的工艺和性能表征并对二氧化硅与硅灰石颗粒间的复合作用机理进行了分析研究。试验采用单因素实验分别研究了二氧化硅与硅灰石在水介质中的分散现象,优化条件下实现了二氧化硅与硅灰石的分散。二氧化硅解聚分散的最佳优化工艺参数为：球料比10：1、浆体浓度10%、研磨时间1.5h、分散剂用量10%,二氧化硅颗粒d50由18.434μm降为3.8μm,d90由44.17μm降为约8μm。对硅灰石分散的最佳优化工艺参数为：机械搅拌时间40min,搅拌转速600r/min,硅灰石颗粒d50从21.718μm下降至19.85μm,粗端粒径d90也从86.592μm下降至83.65μm；研究了采用机械力化学法制备二氧化硅/硅灰石复合颗粒材料各主要工艺因素的影响。制备二氧化硅/硅灰石复合颗粒材料的优化工艺为：二氧化硅与硅灰石比例为3：7,复合转速1200r/min,反应时间40min,球料比5：1,分散剂用量为6%；研究了二氧化硅/硅灰石复合颗粒材料的微观形态及其复合作用机理。复合颗粒主要由二氧化硅颗粒团聚体较均匀的包覆在硅灰石颗粒表面所形成,部分颗粒间存在着相互穿插。在二氧化硅/硅灰石复合颗粒上,二氧化硅与硅灰石之间通过各自表面羟基间的脱羟基作用实现具有化学性质的结合。
[Abstract]:The composite of particles is an important way to construct new materials. It can also promote the functionalization of particles through particle compounding. The new materials can change the surface properties of single particles and improve the dispersion of particles. Fluidity and other properties. Silica has excellent physical and chemical properties in plastics. Rubber and other industrial fields have a wide range of applications. Amorphous silica particles or film coated on the surface of wollastonite to prepare the composite particles can play the role of the reinforcement of silica particles. It can also eliminate the edges of wollastonite particles, resulting in rough surface, so as to solve the problem of poor compatibility between wollastonite and matrix. In this paper, the mechanochemical method is used to depolymerize and disperse silica particles. Silica / wollastonite composite particles were prepared by the dispersion of wollastonite and the combination of the two wet grinding methods. The influencing factors in the preparation process were investigated and optimized. The preparation process and properties of composite granular materials were studied, and the mechanism of composite interaction between silica and wollastonite particles was analyzed. The single factor experiment was used to study the effect of silica and wollastonite on silica and wollastonite. Dispersion in water media. Under the optimized conditions, the dispersion of silica and wollastonite was realized. The optimum technological parameters of silica depolymerization and dispersion were as follows: ratio of ball to material 10: 1, slurry concentration 10: 1, grinding time 1.5 h. When the amount of dispersant was 10, the d50 of silica particles decreased from 18.434 渭 m to 3.8 渭 m. D90 was reduced from 44.17 渭 m to about 8 渭 m. The optimum technological parameters for wollastonite dispersion were as follows: mechanical stirring time 40 min, stirring speed 600 rpm. The d50 of wollastonite particles decreased from 21.718 渭 m to 19.85 渭 m, and the coarse end diameter d90 decreased from 86.592 渭 m to 83.65 渭 m. The influence of main technological factors on the preparation of silica / wollastonite composite granular material by mechanochemical method was studied. The optimized process of preparing silica / wollastonite composite granular material was as follows:. The ratio of silica to wollastonite is 3: 7. The compound speed is 1200 r / min, the reaction time is 40 min, the ratio of ball to material is 5: 1, and the amount of dispersant is 6. The microstructure and mechanism of silica / wollastonite composite particles were studied. The composite particles were mainly formed by the homogeneous coating of silica particles on the surface of wollastonite particles. On the silica / wollastonite composite particles, silica and wollastonite have chemical properties through the dehydroxylation of hydroxyl groups on the surface of the silica / wollastonite composite particles.
【学位授予单位】：辽宁科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TQ127.2;TB33

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