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Nessuna fiera in programma
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POLYOLEFINS
Polyolefins may be: Polypropylene (PP) is a homopolymer obtained by continuous polymerisation in the presence of catalysts. The polymer is colourless, odourless and translucent. It has good physical and mechanical properties with minimal water absorption and permeability, and it withstands chemicals well. Polyethylene (PE) is a polymer of ethylene. It has good chemical resistance and impact strength and excellent electrical properties, is unaffected by water and has low permeability to steam. When cross-linked (XLPE) it has a higher modulus of elasticity and strength under load at high temperatures and excellent resistance to creep and stress cracking problems.
Ethylene copolymer - vinyl acetate (EVA) is a copolymer obtained by synthesis at high pressure. The vinyl acetate content may be low (10-15%), medium (45%) or high (70-90%). It has good flexibility, resists impacts above all at low temperatures and has good elongation and good load absorption properties.
PVC
Polyvinyl chloride is an amorphous halogen thermoplastic polymer with a very low degree of residual crystallinity (max 5%). PVC is a very widely used polymer due to its competitive quality/price ratio. In view of its considerable chlorine content it is non-flammable below the decomposition temperature. When heated, it incorporates a large quantity of plasticisers, which make its behaviour similar to that of elastomers. In the rigid state it is hard and transparent, has high resistance to both acid and basic chemicals, and has poor resistance to ketones and aliphatic and aromatic hydrocarbons. The resistance to ageing is high. Rigid at ambient temperature, it has good resistance to UV ageing, poor impact strength and good electrical properties, and is waterproof.
THERMOPLASTIC ELASTOMERS (TPE)
The TPEs of interest to us are the Urethane (TPU) and Olefin (TPV) types. TPUs are copolymers with alternating rigid and elastomer segments; they have good resistance to oils and abrasion, can be used to produce transparent products, and have good adhesion to metal substrates and other materials. TPVs are obtained by mixing PP with EPDM and have high rigidity and softening point, proportional to the percentage of PP in the mix. They have good resistance to temperature, low specific weight and acceptable resistance to weather. |
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| SILTEK s.p.a.
Via Bergamo 60, 26022 Castelverde (CR) Italy tel: +39 0372 424411 fax : +39 0372 429424 |
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