A sulfonate group-containing copolymer is provided which comprising a structural unit (a) derived from a sulfonate group-containing monomer (A); a structural unit (b) derived from a (poly)oxyalkylene monomer (B); a structural unit (c) derived from a carboxyl group-containing monomer (C). The sulfonate group-containing copolymer comprises from 20% to 90% by mass in an acid form equivalent of the structural unit (c) in 100% by mass of all the structural units constituting the sulfonate group-containing copolymer. The product (P×Mw×n) of the ratio by mass P of the structural unit (b) to the structural unit (a) multiplied by the weight average molecular weight Mw of the sulfonate group-containing copolymer multiplied by the value n is from 950,000 to 800,000,000.

To provide a process for producing a fluoroolefin copolymer powder for powder coating material, which presents excellent stability of a fluoroolefin copolymer solution obtainable by polymerization in its production process, and which is capable of forming a cured film having an excellent appearance when used for a powder coating material. A monomer mixture comprising specific monomers is polymerized in an organic solvent in the presence of specific amounts of hydrotalcite and at least one compound (B) selected from a potassium salt, a sodium salt, a magnesium salt and a hindered amine-type light stabilizer, to obtain a suspension; an insoluble component is removed from the suspension to obtain a fluoroolefin copolymer solution having a pH of from 3.8 to 6.5 and an APHA value within a range of from 1 to 200; and the organic solvent is removed from the solution to obtain the fluoroolefin copolymer powder.

Provided is a method for efficiently producing on an industrial scale a high-performance polyvinylamine solution having good handling properties. After producing a polymer containing N-vinylcarboxamide monomer units having a value of the weight average molecular weight (Mw)/number average molecular weight (Mn) of 5 or higher by aqueous solution standing adiabatic polymerization, the polymer is hydrolyzed in an aqueous solvent in the presence of an alkali and an antigelling agent. In a preferred embodiment of the present invention, a polymer powder having a volatile content of 0.1-12% by mass is obtained by drying and pulverizing after producing a (co)polymer, and the powder obtained is stored or transported to the site of use of the polymer solution and hydrolyzed in an aqueous solvent in the presence of an alkali and an antigelling agent when the polymer solution is needed or at the site of use of the polymer solution.

Provided is a method for efficiently producing on an industrial scale a high-performance polyvinylamine solution having good handling properties. After producing a polymer containing N-vinylcarboxamide monomer units having a value of the weight average molecular weight (Mw)/number average molecular weight (Mn) of 5 or higher by aqueous solution standing adiabatic polymerization, the polymer is hydrolyzed in an aqueous solvent in the presence of an alkali and an antigelling agent. In a preferred embodiment of the present invention, a polymer powder having a volatile content of 0.1-12% by mass is obtained by drying and pulverizing after producing a (co)polymer, and the powder obtained is stored or transported to the site of use of the polymer solution and hydrolyzed in an aqueous solvent in the presence of an alkali and an antigelling agent when the polymer solution is needed or at the site of use of the polymer solution.

The present disclosure relates to a cement additive composition including a polycarboxylic acid-based copolymer. When the cement additive composition of the present disclosure is used for cement formulation, it may improve fluidity of the composition even in a high water reducing ratio range of the particle and effectively prevent slump loss of the cement formulation, while improving initial dispersibility due to excellent water reducing performance.

Described herein is a perfluoropolymer and compositions therefrom. The perfluoropolymer is derived from: (a) no more than 88 mol % tetrafluoroethylene monomer; and (b) a complementary amount of a perfluoro (cycloaliphatic methyl vinyl ether) monomer, and has substantially no melting point.

A composition comprising a mixture of fluoropolyether acids or salts having a number average value of about 800 to about 2500 g/mol. The amount of fluoropolyether acids or salt in the mixture having a molecular weight of not more than 500 g/mol is not more than 50 ppm by weight of the total amount of fluoropolyether acids or salts in the mixture. The amount of fluoropolyether acids or salts in the mixture having a molecular weight of 2500 g/mol or greater is not more than 40% by weight of the total amount of fluoropolyether acids or salts in the mixture. Preferably the fluoropolyether acids or salts comprise an anionic group selected from the group consisting of carboxylate, sulfonate, sulfonamide anion and phosphonate. Also disclosed is an aqueous dispersion polymerization process for fluoropolymer manufacture employing polymerization agent comprising the specified mixture of fluoropolyether acids or salts.

The present invention is directed to partially fluorinated copolymers and the production thereof. More specifically, the copolymers, which are preferably produced by a solution polymerization process, preferably have at least three units, the first unit selected from 2,3,3,3-tetrafluoropropene and 1,3,3,3-tetrafluoropropene, the second unit having a polymerized monomer selected from the vinyl esters and vinyl ethers, and the third unit having a polymerized monomer derived from a hydroxyl group-containing vinyl ether. The resulting copolymer is environmentally friendly, has favorable molecular weight characteristics, and may be shipped economically in high concentration.

To provide an ion exchange membrane for alkali chloride electrolysis which has high membrane strength and low membrane resistance, thereby capable of reducing the electrolysis voltage during alkali chloride electrolysis. In this ion exchange membrane (1) for alkali chloride electrolysis, a reinforcing material 20 formed by weaving reinforcing yarns 22 and sacrificial yarns 24 is disposed in a layer (S) 14, and layer (S) 14 has elution portions 28 formed by elution of at least portions of the sacrificial yarns 24. In a cross section perpendicular to reinforcing yarns of the warp, the average distance (d1) from the center of a reinforcing yarn 22 to the center of the adjacent reinforcing yarn 22, the total area (P) obtained by adding the cross-sectional area of an elution portion 28 and the cross-sectional area of a sacrificial yarn 24 remaining in the elution portion 28, the number (n) of elution portions between adjacent reinforcing yarns 22, and the ion exchange capacity of a layer (Sa) located on the most anode side in the layer (S) 14 during alkali chloride electrolysis, are controlled to be within specific ranges, respectively.

An amphoteric betaine-type polycarboxylic acid water reducer and a preparation method therefor are provided in the present invention. An unsaturated betaine-type monomer A and an acrylic acid-type polyethylene glycol monomer B are placed in a reaction container, stirred until uniform and then an acrylic acid-type monomer C is added, the stirring is continued and water is added to make adjustments so as to make the total mass of the monomers account for 10%-20% of the total mass of the aqueous solution; and under the protection of an inert gas, the temperature is raised to 60° C.-100° C., an aqueous initiator solution is added, maintaining the temperature and reacting for 4-6 h, and after the reaction is completed, the solution is cooled to room temperature, and the pH value thereof is adjusted to 5-7 to prepare the amphoteric betaine-type polycarboxylic acid water reducer.