METHOD FOR IMPROVING GAS-BLOCKING PROPERTY OF NBR SHEET

摘要

PURPOSE:To efficiently improve the gas-blocking property of an NBR rubber sheet useful for oil-resistant hoses, etc., without losing its rubber elasticity as a whole, by immersing an NBR rubber sheet in saturated bromine water to make a treatment under specified conditions. CONSTITUTION:An NBR rubber sheet 3 is immersed in saturated bromine water 4 followed by irradiation of ultraviolet light from e.g. a low-pressure mercury lamp 1 for 0.5-3hr to make a photobromination of one side of the rubber sheet 3 until the bromine content of the sheet come to ca.10wt.% on an average sheet thickness, thus improving the gas blocking ability of the NBR sheet 3 without significantly losing its rubber elasticity as a whole.