Graft polymerization preformer and method of manufacturing the same

Claim 1

A method of manufacturing a graft polymerization preformer comprising the steps of suspending (a) 100 parts by weight of ethylene homopolymer, copolymer or mixture thereof in (b) water, adding to the resultant suspension a solution obtained by dissolving in (c) 5 to 400 parts by weight of one or more vinyl monomers selected from the group consisting of vinyl aromatic monomers, acrylic or methacrylic ester monomers and mixtures thereof, acrylonitrile, methacrylonitrile and vinyl ester monomers, (d) from 0.1 to 10 parts by weight, with respect to 100 parts by weight of said vinyl monomer, of one or more radical polymerizable organic peroxides represented by the formula ##STR3## where R 1 represents a hydrogen atom or an alkyl group with a carbon number of 1 to 2, R 2 a hydrogen atom or a methyl group, R 3 and R 4 respective alkyl groups with carbon numbers of 1 to 4, R 5 an alkyl, phenyl or alkyl-substituted phenyl group with a carbon number of 1 to 12 or a cycloalkyl group with a carbon number of 3 to 12, and m is 1 or 2, or the formula ##STR4## where R 6 represents a hydrogen atom or alkyl group with a carbon number of 1 to 4, R 7 a hydrogen atom or a methyl group, R 8 and R 9 represents alkyl groups with carbon numbers of 1 to 4, R 10 and alkyl, phenyl or alkyl-substituted phenyl group with carbon number of 1 to 12 or cycloalkyl group with carbon number of 3 to 12, and n being 0, 1 or 2, and (e) radical polymerization initiator with a decomposition temperature of 40° to 90° C. for a half reduction period of 10 hours such that it constitutes 0.01 to 5 parts by weight per 100 parts by weight of the sum of said vinyl monomer(s) and said radical polymerizable organic peroxide, heating the resultant mixture under a condition that decomposition of said initiator does not substantially take place whereby to impregnate said ethylene polymer with said vinyl monomer(s), radical polymerizable organic peroxide and radical polymerization initiator, and when the content of free vinyl monomer(s), radical polymerizable organic peroxide and radical initiator is reduced to be 50% by weight or less of the initial value, elevating the temperature of said water suspension to cause copolymerization of said vinyl monomer(s) and said radical polymerizable organic peroxide in said ethylene polymer.

Claim 2

A method of manufacturing a graft polymerization preformer comprising the steps of suspending (a) 100 parts by weight of ethylene homopolymer, copolymer or mixture thereof in (b) water, adding to the resultant suspension a solution obtained by dissolving in (c) 5 to 400 parts by weight of one or more vinyl monomers selected from the group consisting of vinyl aromatic monomers, acrylic or methacrylic ester monomers and mixtures thereof, acrylonitrile, methacrylonitrile and vinyl ester monomers, (d) from 0.1 to 10 parts by weight, with respect to 100 parts by weight of said vinyl monomer, of one or more radical polymerizable organic peroxides represented by the formula ##STR3## where R 1 represents a hydrogen atom or an alkyl group with a carbon number of 1 to 2, R 2 a hydrogen atom or a methyl group, R 3 and R 4 respective alkyl groups with carbon numbers of 1 to 4, R 5 an alkyl, phenyl or alkyl-substituted phenyl group with a carbon number of 1 to 12 or a cycloalkyl group with a carbon number of 3 to 12, and m is 1 or 2, or the formula ##STR4## where R 6 represents a hydrogen atom or alkyl group with a carbon number of 1 to 4, R 7 a hydrogen atom or a methyl group, R 8 and R 9 represents alkyl groups with carbon numbers of 1 to 4, R 10 and alkyl, phenyl or alkyl-substituted phenyl group with carbon number of 1 to 12 or cycloalkyl group with carbon number of 3 to 12, and n being 0, 1 or 2, and (e) radical polymerization initiator with a decomposition temperature of 40° to 90° C. for a half reduction period of 10 hours such that it constitutes 0.01 to 5 parts by weight per 100 parts by weight of the sum of said vinyl monomer(s) and said radical polymerizable organic peroxide, heating the resultant mixture under a condition that decomposition of said initiator does not substantially take place whereby to impregnate said ethylene polymer with said vinyl monomer(s), radical polymerizable organic peroxide and radical polymerization initiator, and when the content of free vinyl monomer(s), radical polymerizable organic peroxide and radical initiator is reduced to be 50% by weight or less of the initial value, elevating the temperature of said water suspension to cause copolymerization of said vinyl monomer(s) and said radical polymerizable organic peroxide in said ethylene polymer.