NON-TACKY PUTTY COMPOSITIONS COMPRISING A LOW MOLECULAR WEIGHT POLYSULFIDE AND A HIGH MOLECULAR WEIGHT POLYSULFIDE ELASTOMER

摘要

Putty compositions which rapidly skin-over and become tack-free are prepared by adding a relatively low molecular weight (500 to 12,000) polysulphide polymer to a high molecular weight (50,000 to 200,000) elastomeric adhesive compound mixed with at least one plasticizer and at least one filler. There may be 1 to 20 parts by weight of low molecular weight polysulphide polymer, 100 to 1500 parts by weight of plasticizer and 100 to 1500 parts by weight of filler per 100 parts by weight of high molecular weight elastomer. In an example, putties are prepared from a high molecular weight polysulphide polymer, a mercaptan terminated polysulphide polymer (molecular weight about 4000) chlorinated biphenyl, calcium carbonate, magnesium silicate, titanium dioxide, toluene and an acrylate resin. The low molecular weight polysulphide polymer also may be terminated by isocyanate groups or amine groups. Other high molecular weight elastomers mentioned are 1-butene homopolymer, isobutylene-isoprene copolymer, styrene-butadiene copolymer, 2-chloro-1,3-butadiene homopolymer and saturated chlorosulphonated polyethylene polymer. Other fillers and plasticizers are listed.