The main components of silica gel

Silica gel is a highly active adsorption material, an amorphous substance, and its chemical formula is mSiO2·nH2O. It is insoluble in water and any solvent, non-toxic and odorless, has stable chemical properties, and does not react with any substance except strong alkali. 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 characteristics that are difficult to replace by other similar materials: high adsorption performance, good thermal stability, stable chemical properties, high mechanical strength, etc.

After silica gel absorbs moisture, it can be regenerated by methods such as exposure to the sun, baking, and air drying.

Chemical composition

The main component is silicon dioxide, which is purified and processed from natural minerals into granular or beaded form. As a desiccant, its microporous structure (average 2A) has a good affinity for water molecules. The most suitable moisture absorption environment for silica gel is room temperature (20~32) and high humidity (60~90%). It can reduce the relative humidity of the environment to about 40%.

Desiccant is a dehumidifier that absorbs moisture from the atmosphere. Its drying principle is to physically adsorb water molecules into its own structure or to chemically absorb water molecules and change its chemical structure into another substance.

Medical silicone is a widely used biomaterial in cosmetic surgery. It comes in many forms, such as liquid silicone oil, jelly-like silicone, foam silicone sponge and elastic solid silicone rubber, among which solid silicone rubber is the most commonly used.

Features

Silicone rubber has good biocompatibility, is non-irritating, non-toxic, has no allergic reaction to human tissue, and has very few body rejection reactions; it has good physical and chemical properties, can maintain its original elasticity and softness during contact with body fluids and tissues, and will not be degraded. It is a fairly stable inert substance. It can withstand high temperatures and can be sterilized. It is easy to process and shape, easy to carve and use.

Classification purpose

Silicone rubber can be divided into two categories: heat-vulcanized silicone rubber and room temperature vulcanized silicone rubber.

Heat vulcanized silicone rubber

It can be made into products of different hardness. It is the most commonly used one in clinical practice and can be pre-carved into any shape. Such as: nasal prosthesis, artificial mandible, skull patch, breast prosthesis, auricle or stent mandibular facial prosthesis materials, artificial joints, artificial testicles, etc.

Room temperature vulcanized silicone rubber

The silicone oil unit completes the vulcanization process at room temperature through the action of a catalyst, and is injected into the required area before it is still liquid and hardened, filling and shaping according to the local defect morphology. However, this method of use has many complications and has been discontinued.