Suitable lower alkyl (meth)arcylates which can be used to prepare the amine-substituted acrylic polymer comprise those having 1 to 8 carbon atoms in the alkyl group such as methyl acrylate, ethyl acrylate, isopropyl acrylate, methyl methacrylate, propyl methacrylate, ethoxyethyl methacrylate, and the like.