What are the differences between liquid silicone and solid silicone?First of all, judging from the literal, liquid silica gel is fluidity, fast hydrophobic, safe and environmental protection, liquid liquid silica gel, solid is showing a solid shape, no flow performance of solid silica gel, high temperature resistance, adhesion resistance, electrical insulation, chemical industry and so on.
Solid silica gel in the industry is mostly sodium silicate as raw material, hydrolyzed into gel in the acidic medium.It is then made into normal silica gel after being aged and dry.Mostly translucent or white solid shape, there are irregular granular, spherical silica gel often used in fluidized bed catalyst carrier.Usually speaking of silica gel penetration and catalytic active components in the solution, so that the solution absorption and silica gel pores dry cremation procedures, so that the active component distribution and silica gel surface, silica gel pore structure has an important impact on the nature of the supported catalyst made, such as silica gel pore volume, pore size distribution.Traditionally, the average pore size is less than 15 ~ 20 silica gel, called fine pore silica gel, the average pore size is greater than 40 ~ 50, called coarse pore silica gel.However, the fine pore structure is not conducive to the diffusion of reactant molecules, but we can reduce the utilization rate of the inner surface of the catalyst, and the product molecules generated in the deep pore are not easy to escape out of the hole, easy to cause deep side reactions.The pore structure of silica gel is related to the manufacturing method and conditions, such as gluing, aging, pH when washing, temperature, time and so on.The commercially available silica gel can be reamed through the reamed method. The usual method is to put it in the autoclave and add water or add saline aqueous solution (such as sodium carbonate, sodium acetate) for hot pressing treatment. For example, after the hot pressing treatment at 320℃ and 10MPa, the silica gel with specific surface and average pore size of 135m2/g and 123 can be changed into 26.9m2/g and 508.
Liquid silica gel is usually used in industry by particle exchange method to make sodium silicate solution, it is translucent.Milky white liquid.High stability performance. Silica sol becomes porous solid after drying. For example, in the preparation of the catalyst for the production of acrylonitrile (phosphorus-molybdenum-bismuth-oxygen)/ silicon oxide from the ammoniation of propylene, the solution containing the active component is mixed with silica sol, and the spray drying method is used to produce microspherical catalyst.Mainly used for food grade, tasteless, transparent, easy to color, adjustable hardness range acid and alkali resistance, etc.
Liquid silica gel and solid silica gel compared to liquid silica gel is easy to process and use, improve the production efficiency.After the solid silica gel is kneaded with a mixer, the cutter works to cut the product and the mold to the appropriate size and thickness, and then it is placed in the mold and molded under a pressure molding machine at a certain temperature.When demoulding is similar to plastic products, it is also necessary to clean the mold.
In fact, liquid silicone products show high transparency, and no odor.Solid silicone products have low transparency, vulcanizing agents or other fragrances that mask vulcanizing agents.
