Sealant material

Claim 1

The sealant composition comprising a coke oven door sealant for coke oven doors and joints and like installations which coke oven doors sealant remains effective as a sealant to prevent gas leakage from coke oven doors and joints and the like at temperatures up to about 200° C., the coke oven door sealant having from about 25 to 55% polyvinyl acetate-based latex, said latex having a solids content of about 50% and having a pH of not less than about 4.5, the sealant having from about 10 to 25% water, and having from about 25 to 45% of a particulate filler, which is finer than 200 mesh British Standard, the coke oven door sealant having from about 5 to 15% of an inorganic fiber, at least about 40% of which fiber will pass through a 100 mesh British Standard sieve, the sealant composition further comprising from about 0.5 to about 5% of a blowing agent which decomposes in the temperature range from about 140° to 225° C. to give off a gas, the blowing agent tending to counteract any shrinkage tendency of the coke oven door sealant being effective as a sealant against gas leakage during a cycle of use, with any shrinkage tendency of the coke oven door sealant being counteracted by the blowing agent, for several hours at temperatures of up to about 200° C. and the coke oven door sealant being effective as a gas sealant and remaining flexible at temperatures of up to about 80° C. for several months.