Abstract: An amphoteric polyelectrolyte which is useful as a paper additive capable of imparting dry strength to paper, a high molecular flocculant, a high molecular dehydrating agent or the like is prepared by copolymerizing a cationic vinyl monomer such as .beta.-methacryloxyethyl trimethylammonium chloride, an anionic vinyl monomer such as acrylic acid and a vinyl monomer such as acrylamide, optionally with a nonionic vinyl monomer such as acrylonitrile, in a solvent in the presence of a catalyst.

Abstract: A process for preparing hydrolyzed acrylamide and methacrylamide polymers which comprises hydrolyzing a powdery acrylamide or methacrylamide polymer dispersed in a solvent mixture comprising water and at least one water-miscible organic solvent selected from the group consisting of ketones, nitriles, ethers and furans.

Abstract: The growth of plants is promoted using a water-soluble cationic polymer obtained by polymerization of a quarternary ammonium compound of the following formula (I) alone or together with other vinyl monomers, ##STR1## wherein R.sub.1 is hydrogen or methyl, R.sub.2 and R.sub.3 are each a lower alkyl, R.sub.4 is a lower alkyl, allyl, a hydroxy(lower)-alkyl, benzyl or --CH.sub.2 COO(CH.sub.2).sub.m CH.sub.3 group (in which m is 0 or 1), X is a halogen or methylsulfate and Y is --O(CH.sub.2).sub.n --, --NH--(CH.sub.2).sub.

Abstract: In the production of a water-soluble, cationic high polymer of (A) at least one of acrylamide and methacrylamide and (B) at least one of ammonium type monomers of either one of the formulas: ##STR1## wherein R.sub.1 is a hydrogen atom or a methyl group, R.sub.2 and R.sub.3 are each a lower alkyl group, R.sub.4 is a hydrogen atom, a lower alkyl group, an aryl group, a hydroxy(lower)alkyl group, a benzyl group or a group of the formula: --CH.sub.2 COO(CH.sub.2).sub.m CH.sub.3 (m being an integer of 0 or 1), R.sub.5 .crclbar. is a group of either one of the formulas: --(CH.sub.2).sub.2 COO.crclbar. and --(CH.sub.2).sub.3 SO.sub.3 .crclbar.

Abstract: In the production of a water-soluble, cationic high polymer of (A) at least one of acrylamide and methacrylamide and (B) at least one of ammonium type monomers of either one of the formulas: ##STR1## wherein R.sub.1 is a hydrogen atom or a methyl group, R.sub.2 and R.sub.3 are each a lower alkyl group, R.sub.4 is a hydrogen atom, a lower alkyl group, an aryl group, a hydroxy(lower)alkyl group, a benzyl group or a group of the formula: --CH.sub.2 COO(CH.sub.2).sub.m CH.sub.3 (m being an integer of 0 or 1), R.sub.5.sup.- is a group of either one of the formulas: --(CH.sub.2).sub.2 COO.sup.- and -(CH.sub.2).sub.3 SO.sub.3.sup.

Abstract: Water-soluble high molecular weight polymers, useful as coagulating agents, are prepared by initiating the polymerization of acrylamide or a monovinyl monomer mixture containing a predominant amount of acrylamide in an acetone-water mixture at a temperature of not lower than 5.degree.C but of lower than 25.degree.C in the presence of polyvinyl alcohol and a catalyst, the concentration of the monomer in the polymerization reaction mixture being 15 to 30 % by weight and the concentration of acetone in the acetone-water mixture being 15 to 35 % by weight, and continuing the polymerization reaction while controlling the viscosity of the reaction system by adding a water-miscible organic solvent having a small chain transfer coefficient to the reaction system with the progress of the polymerization reaction.

Abstract: A polymeric flocculant composition having an excellent flocculation effect, which comprises (a) an acrylamide polymer containing 50 or more molar % of an acrylamide unit and (b) at least one amino resin precondensate selected from the group consisting of urea-formaldehyde, melamine-formaldehyde, guanidine-formaldehyde and dicyandiamide-formaldehyde, wherein the acrylamide polymer and the amino resin precondensate are admixed in a ratio of 90 : 10 to 99 : 1 by weight. The polymeric flocculant composition disclosed herein is useful for cleaning waste water.

Abstract: High molecular weight acrylamide polymers useful as flocculants are obtained by copolymerizing acrylamide with a monovinyl monomer in a mixture of water and acetone in the presence of a redox type catalyst comprising a persulfate, an aliphatic amine and at least one Lewis acid selected from the group consisting of chlorides and bromides of aluminum, antimony, lithium and zinc.