Abstract: Herein disclosed are a novel methacrylic copolymer capable of serving as a component for uniformly dispersing pigments in paints and varnishes and a dispersant comprising the copolymer. The dispersant for dispersing pigments in non-aqueous paints and varnishes comprises a methacrylic copolymer obtained by copolymerizing 10 to 85 parts by weight of at least one (meth)acrylate monomer selected from, for instance, alkyl (meth)acrylates, alkenyl (meth)acrylates, hydroxyalkyl (meth)acrylates and alkylalkenyl monoalkylene glycol (meth)acrylates, 10 to 60 parts by weight of aminoalkyl (meth)acrylate monomer and/or quaternary ammonium (meth)acrylate monomer and 5 to 30 parts by weight of a monomer carrying a terminal (meth)acryloyl group and having an average molecular weight ranging from 4000 to 1000000.

Abstract: The present invention relates to a reactive vinyl polymer having (meth)acryloyl groups on the side chains obtained by radical-copolymerizing a monofunctional (meth)acrylate with a polyfunctional (meth)acrylate under specific conditions in a solvent as well as a method for preparing the same. In order to prevent the occurrence of gelation during the copolymerization, a long chain alkyl group or the like is introduced into the monofunctional (meth)acrylate to control a crosslinking reaction while making use of the steric effect of the long chain alkyl group or the like. The vinyl polymer of the present invention is effective for use as a photo hardenable and thermo setting gluing agent or adhesive and a resin for gluing agents and adhesives, further it serves as a functional polymeric material and thus can be incorporated into other resins.