General knowledge and application of vinyl silicone oil

The commonly used vinyl silicone oil is divided into vinyl-terminated silicone oil (Vi-PDMS) and vinyl-terminated side-chain vinyl silicone oil (Vi-PDVS).

The preparation process and reaction mechanism of vinyl silicone oil are similar to that of dimethyl silicone oil: a small number of methyl (Me) in polydimethylsiloxane is replaced by vinyl (Vi) to form a reactive polymethylvinylsiloxane. It is generally formed by ring-opening equilibrium reaction with octamethylcyclotetrasiloxane, tetramethyltetravinylcyclotetrasiloxane as raw materials, tetramethyldivinyldisiloxane or hexamethyldisiloxane as blocking agent under the catalysis of acid or base.

Therefore, vinyl silicone oil is a kind of polyorganosiloxane with chain structure of different degree of polymerization, and its form is liquid flow.

The main characteristics of vinyl silicone oil are colorless, odorless, non-toxic, non-volatile liquid, insoluble in water, miscible with benzene, dimethyl ether, methyl ethyl ketone, tetrachlorocarbon or kerosene, slightly soluble in acetone and ethanol. It has low vapor pressure, high flash point and ignition point, and low freezing point; With the different number of chain segments n, the molecular weight increases, and the viscosity also increases. This vinyl silicone oil can have different viscosities.

Where is vinyl silicone oil used?

1. Used as the base material for the production of high-temperature vulcanized silicone rubber (HTV), mixed with crosslinking agent, reinforcing agent, colorant, structure control agent, aging agent, etc. to prepare high-temperature vulcanized silicone rubber raw rubber;

2. It is used to make liquid silicone rubber and is the main material of injection thermoforming silicone rubber;

3. Vinyl silicone oil can react with polyurethane, acrylic acid and other organic materials to make new materials with better performance (weather resistance, aging resistance, UV resistance, enhanced toughness, etc.), such as various modified coatings;

4. Organic silicone lotion (a form of silicone oil, namely emulsified silicone oil) mainly includes silicone oil fabric softening finishing agent; Silicone oil lotion defoamer: it is a defoamer widely used in silicone defoamers with large amount.