Silicone material is a highly active adsorbent material, is an amorphous material. The main component of silica gel is silica, chemically stable and does not burn
hemical formula xSiO2·yH2O. Transparent or creamy granular solid. Has an open porous structure, strong adsorption, can adsorb a variety of substances. Diluted sulfuric acid (or hydrochloric acid) is added to an aqueous solution of water glass and allowed to stand, and it becomes a hydrous silicic acid gel and is solidified. Wash the electrolyte with Na+ and SO4 2-(Cl-) ions dissolved in water and dry it to obtain silica gel. If it absorbs moisture, the amount of moisture absorbed by some silica gel is about 40% or even 300%. For gas drying, gas absorption, liquid dehydration, chromatographic analysis, etc., also used as a catalyst. Cobalt chloride, for example, is blue when dry and red after absorbing water. Reusable repeatedly.
Inorganic silica gel is a highly active adsorbent material and is usually prepared by reacting sodium silicate with sulfuric acid and is subjected to a series of post-treatment processes such as aging and soaking. Silica is an amorphous material, its chemical formula is mSiO2. nH2O. It is insoluble in water and any solvent, non-toxic and odorless, chemically stable, and does not react with any substances except strong alkali and hydrofluoric acid. Various types of silica gel form different microporous structures due to their different manufacturing methods. The chemical composition and physical structure of silica gel determine that it has many other similar materials that are difficult to replace: high adsorption performance, good thermal stability, chemical stability, high mechanical strength, etc., used as a desiccant at home, humidity Regulators, deodorants, etc.; industrial use as oil hydrocarbon bleaching agent, catalyst carrier, pressure swing adsorbent, etc.; Separation and purification agent for fine chemicals, beer stabilizer, coating thickener, toothpaste friction agent, matting agent, etc.
use of norganic silicone
It can be used as a desiccant and can be reused. Silica gel is a porous material with different particle sizes that are suitably dehydrated from silicic acid gels mSiO2.nH2O. With an open porous structure, the specific surface area (surface area per unit mass) is large, it can adsorb many substances and is a good desiccant, adsorbent and catalyst carrier. Adsorption of silica gel is mainly physical adsorption, which can be regenerated and used repeatedly. In the alkali metal silicate (such as sodium silicate) solution by adding acid, acidification, and then add a certain amount of electrolyte for stirring, that is, to generate silicic acid gel; or in the more concentrated sodium silicate solution add acid or Ammonium salts also produce silicate gels. The silicic acid gel is allowed to stand for several hours to be aged, and then the soluble salts are washed away with hot water, dried at 60-70°C and activated at about 300°C to obtain silica gel. The silicic acid gel is soaked in a solution of cobalt chloride and then dried and activated to obtain a color-changing silica gel. When it is used as a desiccant, it is blue before absorbing water and red after absorbing water. The degree of water absorption can be seen from the change of color, and whether or not regeneration is required. Silica gel is also widely used in vapor recovery, petroleum refining and catalyst preparation. Silicone can also be used as a mobile phone case, with extremely high drop resistance
Organosilicon is an organosilicon compound. It refers to a compound containing Si—C bonds and at least one organic group is directly connected to silicon atoms. It is customary to also make organic groups and silicon through oxygen, sulfur, and nitrogen. Atomic linked compounds also act as organosilicon compounds. Among them, the polysiloxanes with silicone-bonded (-Si-O-Si-) skeletons are the most numerous organosilicon compounds, the most studied and most widely used, accounting for more than 90% of the total.
It can be divided into 4 types:
Molded sproducts are usually pressed through a vulcanizing machine after being put into a solid silicone raw material containing a vulcanizing agent through a high-temperature mold, and high-temperature sulfur is formed into a solid. The hardness of the molded silica gel is usually from 30°C to 70°C. Raw materials with color paste in accordance with Pantone color card number to draw the color, the shape of the mold determines the shape of molded silicone products, molded silicone products are the most widely used in the silicone industry. Mainly used for only silicone industrial accessories, buttons, silicone gifts, silicone bracelets, silicone watches, key bags, mobile phone sets, silicone kitchen utensils, silicone mats, ice trays, cake molds and so on.
Products are usually formed by squeezing silicone through an extrusion machine. Generally, the shape of the extruded silicone is long, and the tubular shape can be freely cut. However, the shape of the extruded silicone is limited, and it is widely used in medical devices and food machinery. use.
Liquid products are injection molded by silicone injection molding. The products are soft and can reach a hardness of 10°C to 40°C. Due to their soft characteristics, they are widely used in artificial body parts, medical silicone breast pads, and so on.
Special products are based on the chemical properties of silicone or the addition of some auxiliary materials. Special silicone products can also have high temperature resistance (up to 330 degrees), food grade (full compliance with US FDA, LFGB standard), medical grade, flame retardant grade. , By adding auxiliary materials can also have, luminous, negative ions, discoloration, and other characteristics.
The use of organic silicone
Since silicone have these excellent properties, their application range is very wide. it Silica gel Not only used as a special material for aviation, cutting-edge technology, military technology departments, but also for various sectors of the national economy, its application scope has been extended to: construction, electrical and electronic, textile, automotive, machinery, leather, paper, chemical light industry, metal And paint, medicine and medical care.