Viton® B-303C

Viton® B-303C is a precompound containing an improved 69%F 'B' type fluoroelastomer. This precompound incorporates a bisphenol cure system that can be optionally compounded with peroxide and coagent for 'dual curing'. Viton® B-303C offers a unique combination of processing and cured characteristics including:

• high quality, smooth extrudate surface and appearance at thickness below .040" or 1.0mm

• excellent 'green' strength that helps maintain extrudate shape as well as enabling draw down to very thin veneer thicknesses

• excellent fuel permeation resistance

• good tensile strength

• good adhesion to other elastomers in multi layer hoses

Viton® B-303C is especially attractive for use in the manufacture of low permeation fuel and filler neck hose for automotive and small engine applications. It also works well for any hose requiring a thin FKM layer. This product is superior in extrusion processability compared to many other types of Viton®, including Viton® B-202, B-600 blends and VTR-7419

When used at a 1 to 1.5 phr level, Carnauba wax and VPA 2 process aids each create a smooth finish and result in good metal release. Combinations of these process aids with Struktol® WS280 can provide other desirable characteristics to some compounds. Viton® B-303C is not suggested for use in applications above 250°C. The heat resistance of B-303C can be maximized by the use of a dual cure system of TAIC and peroxide in conjunction with the incorporated bisphenol cure. See compound A40-06 in Table I for a dual cure example.