Silicone rubber according to its curing temperature, can be divided into high temperature heating vulcanization (HTV) and RTV (RTV) two categories, high temperature plastic is mainly used in the manufacture of various silicone rubber products, while the room temperature plastic is mainly used as an adhesive , Potting materials or mold use.
1. Heat-cured silicone rubber (HTV)
Heat-vulcanized silicone rubber (HTV) is the most important category of silicone products. Methyl vinyl silicone rubber (VMQ) is the most important type in HTV, commonly known as high temperature adhesive. Methyl vinyl silicone rubber (raw rubber) is a colorless, odorless, non-toxic, no mechanical impurities jelly, raw rubber, according to the need to participate in the appropriate reinforcing agent, the structure of the controller, curing agent and other additives mixed with Refining, and then heating molding or extrusion molding, and then by the second curing made into various types of finished products. Its finished products have excellent electrical insulation, anti-arcing, corona, EDM can be strong, waterproof, moisture, impact resistance, good shock resistance, with psychological inertia, permeability and other functions.
Mainly used in aviation, instrumentation, electronics, sail, metallurgy, machinery, automobiles, medical and health and other parts, can do all kinds of seals, gaskets, tubes, cables, can also do human organs, blood vessels, breathable membrane And rubber molds, fine forging release agent.
2. RTV silicone rubber (RTV)
Room temperature vulcanized silicone rubber is generally a condensation type and additive two categories.
Condensation RTV silicone rubber is based on the condensation reaction between silanols and other active substances characterized by crosslinking at room temperature as an elastomer silicone rubber, the product is divided into two-component packaging and two-component packaging the way. One-component room temperature vulcanized silicone rubber (referred to as RTV-1 plastic) is the condensation of liquid silicone rubber one of the primary products. Vancomycin from the bottom of the polymer, crosslinking agent, catalyst, filler and additives formulated from. Products packaged in a sealed tube, the use of extrusion, the air can be self-curing vulcanized elastomer, the use of extremely convenient. Vulcanized rubber can be used for a long time at temperature (-60 ~ + 200 ℃), it has excellent electric gas cutting edge function and chemical invariance, it can withstand water, ozone and weather. It is superior to many kinds of metal and nonmetal materials Of the adhesiveness. Mainly used for various types of electronic components and electrical equipment coating, encapsulation of information from the insulation, moisture, shock effect; as a semiconductor device to maintain the appearance of the material; can also be used as a sealed gap filler and flexible adhesives.
Addition of room temperature plastic is based on a linear polysiloxane with vinyl as the base glue, with hydrogen siloxane as a cross-linking agent, depositors in the catalyst at room temperature to moderate temperature under the influence of cross-linking reaction and become elastomers. It has excellent heat resistance, hydrophobicity, electrical insulation, but also becauseof the introduction of active end groups, it has excellent physical and mechanical functions, especially in the tensile strength, relative elongation and tear strength on a clear improvement. It is used in a variety of vulcanization methods, such as radiation vulcanization, peroxide vulcanization and addition molding vulcanization. It is widely used in heat-resistance, moisture-proof, electrical insulation, high-strength silicon rubber products and so on.