1. Liquid silicone is in a liquid state and has fluidity. It is a high-transparent and high-safe food-grade material. It is not added with auxiliary materials such as vulcanizing agent during molding, and is sealed and molded.
2, solid silica gel is solid state, no fluidity, he is also a transparent environmentally friendly material, the need to add vulcanizing agent to accelerate the vulcanization molding time, open mold injection molding.
Second, the difference between liquid silicone and solids in the field of use
1. Liquid silicone is generally used in baby products and kitchen supplies as well as medical supplies. It can directly contact food and human body.
2, solid silicone is generally used in daily necessities and industrial miscellaneous items and auto parts.
3, the safety of liquid silica gel and solid silica gel: liquid silica gel is a high transparent and high-safe food grade material, no auxiliary materials such as vulcanizing agent are added during molding, and the sealing material is formed by sealing. Solid silica gel is a transparent material. It needs to be vulcanized to accelerate the vulcanization molding time and form mold by open molding.
Third, the difference between the molding method of liquid silica gel and solid silica gel
1. Liquid silicone is injection molding liquid silicone rubber (LSR): the full name is injection molding liquid silicone rubber, and the vulcanization equipment is injection molding machine.
Injection molding machine has a very simple process (no need for high-temperature glue process ingredients, rubber mixing, cutting materials, arranging and other manual processes, just one
A worker can take the product), the product has high precision (all manual procedures are replaced by machines before molding), and the output is high (A/B glue is mixed in
It can be molded in a few seconds at a certain temperature, saving people, saving electricity, saving materials and many other advantages, and can produce all products produced by high temperature glue.
Liquid silica gel is industrially used to dehydrate sodium water to a silica sol by ion exchange. It is a translucent milky white liquid with high stability. The silica sol becomes a porous solid upon drying. The specific molding process is as follows:
(1) Mixing: This ready-to-use material can be colored and catalyzed according to your processing equipment and end use.
(2) Base stock: This type of silicone polymer also contains a reinforcing filler. The rubber base stock can be further compounded with pigments and additives to form a rubber compound to meet your color and other manufacturing requirements.
(3) Liquid silicone rubber (LSR): This two-component liquid rubber system can be pumped into a suitable injection molding equipment and then thermally cured into a molded rubber part.
(4) Fluorosilicone rubber compound and base material: Fluorosilicone rubber maintains many key properties of silicone, and it also has superior chemical, fuel and oil resistance.
A synthetic rubber in which a main chain is composed of silicon oxygen atoms alternately and having an organic group on a silicon atom. The organic group in the molecule may be -CH3, -C2H3 or -C6H5, etc., and is referred to as methyl, vinyl or methylphenyl silicone rubber. Silicone rubber is a special rubber that is resistant to high and low temperatures (-60 to 250 ° C), ozone resistant and has good electrical insulation properties.
Silicone rubber is a special synthetic elastomer formed by linear polysiloxane mixed with reinforcing filler and vulcanized under heat and pressure. It perfectly balances mechanical and chemical properties to meet today's demanding applications.
2, solid silicone molding is the raw material is a piece of solid, after mixing by the mixer, the cutting machine cut into products and molds suitable for large
Small and thick, after being placed in the mold, the pressure forming machine is molded at a certain temperature. When demolding is similar to plastic products, it is also necessary to clean the mold.
(1) Solid silica gel is industrially made of water glass (sodium silicate) as a raw material, hydrolyzed in an acidic medium to form a gel, and then made into a silica gel by aging, washing, drying, etc., depending on the water content, half Transparent or white solid. Commercially available products have irregular granular, spherical, microspherical silica gel, which is often used as a catalyst carrier in fluidized bed operations.
(2) When used as a catalyst carrier, the silica gel is usually immersed in a solution containing a catalytically active component, so that the solution is absorbed into the pores of the silica gel, and the active component is distributed on the surface of the silica gel by drying, activating, and the like. The pore structure of the silica gel has an important influence on the properties of the prepared supported catalyst, such as the pore volume and pore size distribution of the silica gel. Conventionally, a silica gel having an average pore diameter of less than 15 to 20 is referred to as a fine pore silica gel; and an average pore diameter of more than 40 to 50 is referred to as a coarse pore silica gel.
(3) However, the pore structure is not conducive to the diffusion of reactant molecules, but it can reduce the utilization of the inner surface of the catalyst, and the product molecules formed in the pores are not easily escaped from the pores, which is liable to cause deep side reactions. The pore structure of the silica gel is related to the manufacturing method and conditions, such as gelation, aging, pH, temperature, time and the like during washing. The commercially available silica gel can be reamed by a reaming treatment method. The usual method is to heat-press it in an autoclave or add a salt-containing aqueous solution (such as sodium carbonate or sodium acetate), for example, at 320 ° C, The 10 MPa hot pressing treatment can change the silica gel having a specific surface area and an average pore diameter of 135 m 2 /g and 123 to 26.9 m 2 /g and 508, respectively.