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 SILICONE RUBBERS |
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(VMQ Vinyl MethylSiloxane)
Renowned chemist Frederick Kipping was a pioneer in the study of organic compounds with carbon and silicon molecules and was responsible for the name ´silicone´. Silicone is a combination of quartz rock and carbon at high temperatures, obtaining a silicon-based rubber. From this basic substance other physical states such as gels, oils and solids are formed.
Silicone has a high transparency, is versatile and an excellent behaviour in different physical and chemical working conditions. It can be transformed by injection, compression moulding, extrusion, autoclave, casting, etc.
Thermal Resistance: Silicone rubberus have an excellent behaviour and stability at temperatures from -55 ºC up to +225 ºC and our THT silicones can work up to +320 ºC in dry heat. There are silicones which can reach working temperatures of -90 ºC, such as the Phenyl-Vinyl-Methyl-Siloxanes (PVMQ). We have special vapour resistant (wet heat) silicones which are stable up to +150 ºC constant temperature.
Non toxicity standards: Inert material which can comply the following international standards for medical, pharmaceutical and foodstuff contact:: FDA CFR 177.2600 (US Food and DrugAdministration),
BgVVBfR cap.15 (Bundesinstitut für Gesundheitlichen Verbraucherschutz Und Veterinärmedizin),
USP Clase VI (US Pharmacopoeia),
EC 1935/2004 Regulation, Journal officiel de la Republique Française brochure 1227.
Non porous Surface: Non adherent to most products and adhesives, silicone is water repellent and water-proof.
Dielectric properties: Silicone rubbers are one of the best electric insulators with the possibility of working from -40 ºC to +180 ºC. We can supply special conductive silicone formulations.
Mechanical properties: Compared to other organic elastomers, silicone does not stand out for its mechanical properties, but combined with its high temperature resistance it is unbeaten by other rubbers. We have specific formulations for high mechanical strength, abrasion resistance, high elasticity, high tear strength, etc.
Weather resistance: Offers excellent resistance to all weather conditions, ozone, pyralene and UV radiation.
Chemical resistance: Silicone rubbers have a good response when in contact with most chemical compounds, but are affected by fats, solvents and petrols.
With fluorosilicones we obtain superb anticorrosion results in most conditions.
Colours: Standard silicone is translucent, but can be pigmented with foodstuff contact approved colours to achieve any RAL upon request. We can also supply luminescent, fluorescent and metallic colours. We transform platinum-cured silicones for those items exposed to sun rays, that need a high transparency or to avoid yellowing due to ageing.
Vulcanisation: Silicone rubbers are vulcanised with different catalysts depending on the process used to vulcanise them. The most common catalysts are:
DBPH (2,5-Dimethyl-2,5-di (tert-butylperoxy) hexane), mostly used for moulding.
DCBP (2,4-dichlorobenzoyl peroxide)
and addition catalysts commonly known as platinum curing, being especially suited for medical, pharmaceutical applications and foodstuff contact used in extrusion.
Post-curing: Peroxide- or platinum-cured silicones must be post-cured at +200 ºC for a minimum of ten hours in air recirculating ovens to remove all volatile residues and make them suitable for foodstuff contact, as well as certifiable as medical grade.
Hardness and density: We offer from 25 Shore A to 90 Shore A hardness in compact silicone(our standard being 65 Shore) and 0.25 gr/cm3 to 0.8 gr/cm3 density in sponge silicones (our standard is 0.25 gr/cm3). 20 shore A compact silicones and 0.15 gr/cm3 are in development and approval stages.
Main products and shapes: Tubes, reinforced tubes, hoses, cords, profile, flat die-cut gaskets, moulded seals, inflatable seals, heat-vulcanised seals, encapsulated o-rings, rectangular profiles, square profiles, moulded parts, sheets, rolls, with textile or metal inserts, multicomponent parts, etc.
Main applications: Pharmaceutical, chemical, medical, aeronautics, space industries, laboratories, foodstuff, cosmetics, packaging, fluids, metal carpentry, construction, lighting, electronics, car industry, machinery manufacturing, etc.
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