Base Polymer Selection Guide
		Relative Cost ¥
Polymer Types		Relative Cost	Usage (Rank)
General Purpose
Natural Rubber	NR	1.0 (Par)	4
Polyisoprene	IR	2.4	--
Styrene Butadiene Rubber	SBR	1.3	5
Polybutadiene Rubber	BR	1.8	--
Ethylene Propylene Rubber	EPDM	3.2	2
Butyl	IIR	2.7	--
Oil Resistant
Butadiene Acrylonitrile (Nitrile)	NBR	2.5	1 (*all types)
Polychloroprene (Neoprene)	CR	4.1	3
Chlorosulfonated Polyethylene (Hypalon®)	CSM	4.4	6
Polyurethane	AU, EU	10.9	7
Epichlorhydrin	CO, ECO	6.8	10
Specialty
Carboxylated Nitrile	XNBR	3.9	*
Hydrogenated Nitrile	HNBR	20.0	*
Silicone	SI	8.5	9
Polysulfide (Thiokol)	T	12.0	--
Fluoroelastomers (Viton®)	FMK	44.0	8
Polyacrylate	ACM	7.2	--
Nitrile / PVC blend	NBR / PVC	2.8	*
¥ (based on raw polymer costs taken from Rubber World, Feb 01 raw material list prices)

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