Butyl

Rubber material The polymer butyl (IIR – isobutylene isoprene – rubber) is an elastomer with a small number of double bonds, produced through co-polymerisation of isobutylene and isoprene.

With careful compounding Butyl has really good tensile strength.
Butyl has very low permeability to air and other gases.
Excellent resistance to ozone, oxidation and sunlight.
Excellent temperature range of -45º C to +130º C for normal compounds and even better with special formulations like cured resin.
Butyl has very low resilience which makes it ideal for vibration damping and shock absorption applications.
Butyl has moderate resistance to abrasion and compression set.
Resistance to chemicals; resistant to most inorganic products. Highly resistant to mineral acids, alkalines and aqueous acids. Not recommended to use in contact with oils, or hydrocarbon solvents.

EPDM

The polymer EPDM, ethylene-propylene rubber, is produced through co-polymerisation of ethylene, propylene and diene monomer, producing a polymer made up of saturated linear macromolecules with a paraffinic structure.

In addition to the base polymer, both EPDM and Butyl contain reinforcing carbon black, fillers, process chemicals, antioxidants and vulcanising agents. After mixing the ingredients into a homogeneous plastic compound, two layers of the rubber are rolled out in a colander to form a double sheet. Vulcanisation is then carried out. The long rubber molecules in the material are cross-linked through heat and pressure, creating an elastic membrane.

Excellent inherent high and low temperature ranges. Typically -45º C to +120º C for standard compounds.
Special compounding can increase some grades to function continually at +140 º C.
E.P’s are inherently resistant to attack by oxygen, U.V., Ozone and extreme weather environments, and will give long service in these conditions.
E.P’s do not have good adhesion properties and expert advice should be sought from our Technical Department about bounding applications.
Resistance to Chemicals; resistant to many chemicals and solvents. Good resistance to many corrosive chemicals. The performance of E.P’s in hot water and high pressure steam is better than in dry heat.