Thermo-reversible elastomer composition comprising a liquid chloroprene polymer and a polyvalent metal oxide or hydroxide

A thermo-reversible elastomer composition comprising 100 parts by weight of a liquid chloroprene polymer having a Brookfield viscosity (measured at 25.degree. C.) ranging from about 3,000 to about 3,000,000 cps containing at least one carboxyl group in the molecule and having a number average molecular weight of from about 500 to about 20,000 and at least 1 part by weight of a metal compound which is a polyvalent metal oxide or hydroxide or a metal salt complex comprising a polyvalent metal oxide or hydroxide, said liquid chloroprene polymer having been prepared by (1) homopolymerizing a chloroprene monomer or (2) copolymerizing a chloroprene monomer with a monomer copolymerizable with the chloroprene monomer, in the presence of an organic solvent having a boiling point of less than about 150.degree. C. at atmospheric pressure which is miscible with a mercapto-carboxylic acid and is selected from the group consisting of aromatic hydrocarbons, aliphatic halogenated hydrocarbons, cyclic ethers, aliphatic alcohols, aliphatic ketones and aliphatic esters and 0.5 to 20 parts by weight of a mercaptocarboxylic acid per 100 parts by weight of the monomers.