SILICONE RUBBER
Silicone Rubber is a totally synthetic product. It is a high performance polymer originally developed to insulate electric motors and generators, silicone rubber is derived from silicon metal and silica sand.
KASTRADE Silicone Profiles are ideal as - Door Seals for Furnaces, Boiler Closure Seals, Lid seals etc.
Silicone profiles can have practically any conceivable shape, from simple geometries (squares, round cords) through to complicated cross sections with hollow chambers in varying dimensions. KASTRADE has already produced several thousand profile shapes, all of which are available to the customer in the form of ready extrusion dies.
WHAT IS SILICONE RUBBER?
Silicon, the second most frequent element on earth, occurs only in the form of compounds such as silicon dioxide and as silicates. Synthesis then produces polysiloxane which can be put to commercial use. It is designed to have plastic qualities over a wide range of temperatures. It can be molded, extruded and laminated to almost any shape. It is cured at elevated temperatures. Once fully cross-linked, it operates satisfactorily over a range of temperatures from -500C to +2600C for long periods. Silicone Rubber offers long life within this temperature range and will not crack, crumble or go hard under these temperature conditions.
The uniqueness about silicone is that it is basically a High-Temperature Vulcanising Synthetic Rubber (HTV) based on the element - Silicon (Si), which is the basic component in silicone Rubber chemistry.
KEY CHARACTERISTICS OF SILICONE RUBBER
Heat Resistance
Silicone rubbers are extremely heat resistant as compared to normal organic rubbers. There is almost no change in properties at 150°C and thus they can be used almost permanently. For their excellent heat resistance, they are widely applied as material for rubber parts that are used at high temperature.
Heat stability from –500C to +2600C is excellent. Silicone Rubber offers long life within this temp range and will not crack, crumble or go hard under these temperature conditions. Tensile strength, elongation and compression set are not significantly affected within this operating temperature.
Cold Resistance
Silicone rubbers are extremely cold resistant. The brittle point of normal organic rubbers is about –20°C to –30°C. In contrast, the brittle point of silicone rubbers is as low as –60°C to –70°C.
Weathering Resistance
Silicone rubbers have excellent weathering resistance, Under the ozone exposure, normal organic rubbers deteriorate tremendously but silicone rubbers remain almost unaffected. Furthermore, even under long term exposure to ultraviolet and weathering, their physical properties remain almost unchanged.
OTHER SALIENT FEATURES
- The family of Silicone rubbers includes those having higher ranges of tear resistance or extended elongation or specific resistance to specific aggressive solvents etc. These family members can be blended or modified to give desired properties for special applications. Further additives can be introduced to provide flame proof or higher properties if required.
- The outstanding rubber elastic properties in terms of both expansion and compression behaviour make silicone Rubber the ideal sealing material for Facades, Doors, Windows & Curtainwall.
- Chemical resistance to mineral oils, weak acids and alkalies is outstanding, making Silicone Rubber the ideal choice for food applications, especially where rubber may need repeated sterilizing or is in contact with additives or preservatives.
- Electric properties are excellent, with high dielectric strength.
- The post curing process following on from extrusion ensures that all volatile components are evaporated out so that silicone profiles can be easily used in medical technology and in contact with food products without any problems.
- The Silicone profiles are neutral to plastics and paints, and can be given a light-fast colour matching exactly to customer colour samples or practically any of the colours in the RAL colour chart.