Silicone rubber is divided into high temperature vulcanized silicone rubber (HTV) and liquid silicone rubber (LSR).
The thermal stability, chemical stability, weather resistance, flame retardant of silicone rubber is second only to fluorine rubber, drug resistance is second to fluorine rubber and neoprene rubber, electrical characteristics and cold resistance is the best.
RTV-2: Basic adhesive structure
With reinforcing filler, crosslinking agent, catalyst, assistant at room temperature to vulcanize into elastomer.
DMC and D4 can be replaced by hydrolyzed materials.
RTV-1
RTV-1 silicone rubber was obtained by introducing the end group of RTV-2 base adhesive into hydrolyzable group-crosslinking agent, and then sealing package with catalyst, reinforcing filler, viscosifier, plasticizer and auxiliary agent. Molded liquid silicone rubber -LTV is a type of LSR and LIMS liquid injection molded silicone rubber is a type of liquid silicone rubber for LTV.
Molded liquid silicone rubber -LTV composition and vulcanization
It is composed of vinyl silicone oil, hydrogen-containing silicone oil, platinum catalyst, reinforcing filler and auxiliary agent.
Sulfurization mechanism: 1: because of the organic nitrogen, phosphorus, sulfur, tin will make the catalyst PT poisoning, affect the sulfurization, so before use to carry out the sulfurization test.
2: neoprene rubber and other synthetic rubber, sulfur compounds, soft PVC, amine cured epoxy resin, PVC insulating tape, resin flux and other will hinder curing, they can not be used at the same time.
3: moisture and moisture will also affect the vulcanization, please store in a dry place.
The application of LTV
* Low strength type: mainly used for coating semiconductor electronic components, encapsulation materials (with shell), to achieve insulation, moistureproof, dustproof, shockproof, improve the purpose of performance stability parameters, but also can prepare a variety of paper isolation agent.
* High strength type: good mechanical properties, can be used as electronic components without shell packaging materials; Good adhesion, can be used as inner protective coating of semiconductor devices, silver powder can be used as conductive adhesive.
* Aviation type: highly transparent material, can make bulletproof glass and aviation binder.
* Medical type: for the treatment of plastic surgery, saddle nose orthopedic and atrophic rhinitis; Beauty; The intraocular lens. * Filling type: flame retardant potting adhesive, foam adhesive, anticorrosive adhesive, paint and ink.
* Liquid injection molding -LIMS: buttons, pacifiers, etc.
* Single component type: adhesives, coatings and inks.
