use of a mercaptocarbonsäure in the manufacture of standard compounds cured liquid carboxylic groups containing chloroprenpolymeren or copolymers

摘要

Liquid chloroprene polymers contg. terminal carboxyl gps. are produced by polymerising chloroprene monomer or mixts. of chloroprene monomer and copolymerisable monomers in the presence of (1) mercaptocarboxylic acids in amts. equiv. to 0.5-20 pts. wt. of thioglycolic acid to 100 pts. wt. of the monomer and (2) organic solvents in amts. of 20-50 pts. wt. to 100 pts. wt. of the monomer under the condition that the wt. ratio of organic solvent/monomer are controlled to 2. The mercaptocarboxylic acids include, e.g. thioglycolic acid, 2-mercaptopropionic acid, thiolactic acid. The organic acids include, e.g. benzene, toluene, xylene, chloroform. the copolymerisable monomers are those contg. =1 H2C=C gp. such as styrene, acrylonitrile, 1,3-butadiene, isoprene, methacrylic acid. The polymerisation is carried out at 0-100 (40-60) degrees C. The conversion of the monomers to polymers are 60-80%. The polymers produced have average molecular wts. of 500-20,000. When blended with metal oxides such as zinc white, magnesia, chelation occurs between carboxyl gps. and metal oxides and heat-reversible cured materials are produced.