Vinyl chloride resin, process for producing the same, and molded object

A method of producing a vinyl chloride resin comprising

• reacting 100 weight parts of a radical-polymerizable monomer with 0.1 to 1 weight part of a polyfunctional monomer to give a copolymer (a−1), where the radical-polymerizable monomer gives a homopolymer having a glass transition point of not lower than −140° C. but lower than −60° C.,
• graft-copolymerizing 40 to 90 weight % of said copolymer (a−1) with 10 to 60 weight % of a mixture monomer (a−2) to give an acrylic copolymer (a), where the acrylic copolymer (a) has a glass transition point of not lower than −45° C. but lower than −30° C., a gel fraction of 50 to 100 weight % and a mean particle diameter of 60 to 250 nm and the mixture monomer (a−2) comprises 100 weight parts of a radical-polymerizable monomer predominantly comprised of a (meth)acrylate which gives a homopolymer having a glass transition point of not lower than −55° C. but lower than −10° C. and 1.5 to 10 weight parts of a polyfunctional monomer,
• and graft-copolymerizing said acrylic copolymer (a) with a vinyl monomer (b) predominantly comprised of vinyl chloride,
• wherein the graft ratio of vinyl chloride to said acrylic copolymer (a) is 0.1 to 5 weight %.

A rigid vinyl chloride resin molded product as obtained by graft-copolymerizing an acrylic copolymer (a) with a vinyl monomer (b) predominantly composed of vinyl chloride

• and comprising a matrix resin predominantly composed of polyvinyl chloride and, as dispersed therein, a particle of said acrylic copolymer (a),
• the graft ratio of vinyl chloride to said acrylic copolymer (a) being 0.1 to 5 weight %,
• said acrylic copolymer (a) having a glass transition point of not lower than −45° but lower than −30° C., a gel fraction of 50 to 100 weight % and a mean particle diameter of 60 to 250 nm and being obtained by graft-copolymerizing 40 to 90 weight % of a copolymer (a−1) with 10 to 60 weight % of a mixture monomer (a−2),
• said copolymer (a−1) being composed of 100 weight parts of a radical-polymerizable monomer which gives a homopolymer having a glass transition point of not lower than −140° but lower than −60° C. and 0.1 to 1 weight part of a polyfunctional monomer,
• and said mixture monomer (a−2) comprising 100 weight parts of a radical-polymerizable monomer predominantly comprised of (meth)acrylate which gives a homopolymer having a glass transition point of not lower than −55° C. but lower than −10° C. and 1.5 to 10 weight parts of a polyfunctional monomer.