Polyvinyl chloride, ozone resistance

Weather Resistance Many rubbers are affected adversely by outdoor exposure, particularly by the traces of ozone, which are always present in the atmosphere and which cause rapid cracking of lightly stressed rubber articles. Nitrile rubber is no exception and thus it is not suitable for use in exposed conditions. However, the incorporation of a proportion of PVC (Polyvinyl chloride) into the nitrile compound results in improved resistance until, with a blend of 70/30 nitrile/PVC, a material with almost complete resistance to ozone attack is produced. The presence of PVC produces stiffer compounds, with lower resiliance and inferior low temperature properties, but the oil and solvent resistance is enhanced. 

Hypalon is a close match to neoprene in most properties, but it is superior in resistance to acids, solvent, ozone and oxidation, and has decidedly better color stability. This rubber can be used instead of polychloroprene or plasticized polyvinyl chloride in many applications. 

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