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Common Foam TypesTypes of foams:
There are several different types of foams: EPDM, Neoprene, PVC, Polyethylene, Polyurethane & PVC/Nitrile.
EPDM
is a synthetic rubber produced from a mixture of ethylene & propylene. Foam offers very good weathering characteristics & resistance to low & high temperatures. Suitable for outdoor use. Neoprene is generally available in single sided form because the cell face does not lend itself to lamination. Offers very good weathering characteristics & ozone resistance. Suitable for outdoor use. Neoprenes are self extinguishing & exhibit good resistance to hydrocarbons.
PVC
is good, general purpose foam with favorable aging characteristics & offers good resistance to UV light, fungi & weathering. Available in different forms from single to double sided, open to closed cell, super soft to hard density. Usually coated with acrylic adhesive they are long aging & do not harden or become brittle in sunlight. PVC foam is generally flame retardant under compression. The presence of plasticisers in the material may migrate into the product being applied to. Can be laminated with other substrates for pecialised applications.
Polyethylene
is generally used for bonding & mounting applications. Being very conformable they offer economical advantages when offered in low densities. Available in different forms from single to double sided, soft to hard density. Usually coated with synthetic rubber adhesive & occasionally acrylic. Foam ages well & is resistant to UV light, fungi & weathering. It does not contain plasticisers & can be used in applications where it may come in contact with plastics. Due to its cellular make up this foam should be limited to maximum compression rates of 20%, after this rupture may occur & the foam will not recover.
Polyurethane
is generally used because of its low cost. Available in different forms from single to double side, soft open cell to highly compressed to form high density foams. Soft open cell foams have poor aging characteristics, become brown when exposed to UV light, weathering & eventually crumble to dust within a few years. High density offer better aging characteristics & resistance to chemicals, fungi & weathering.
PVC/Nitrile
a general purpose closed cell foam that exhibits similar characteristics to EPDM & Neoprene’s. Usually coated with acrylic adhesive they are long aging & have good resistance to weathering & high temperatures. Foam is generally flame retardant under compression.
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