The disclosure discloses a method for synthesizing magadiite/PMMA nano composite microspheres by using pH value regulation in a Pickering emulsion. According to the method, organic modified magadiite is used as an emulsifier, deionized water of which a pH value is regulated with a buffer solution is used as a solvent, and a methylmethacrylate monomer is used as an oil phase of a Pickering emulsion; stirring is performed to form the stable Pickering emulsion, and then a water-soluble free-radical initiator is added to initiate emulsion polymerization, thereby synthesizing magadiite/PMMA nano composite microspheres.

Provided is a porous membrane that can be manufactured in uncomplicated steps, has high hydrophilicity and water permeability, and exhibits excellent anti-fouling properties when used in a membrane bioreactor method (MBR method). The porous membrane of the present invention is a porous membrane containing polymer (A) and polymer (B), wherein the polymer (A) is a membrane-forming polymer, the polymer (B) is a polymer having a unit (b1) represented by formula (1) and a unit (b2) based on hydroxyl group-containing (meth)acrylate, and the concentration (mass %) of the unit (b1) is equal to or higher than the concentration (mass %) of the unit (b2) in the porous membrane. ##STR00001##

Methods for manufacturing a polymer dispersion, polymer dispersions, and their use are provided herein. The methods of manufacturing the polymer dispersion comprise the steps of providing a reaction mixture in an aqueous medium comprising a polymeric dispersant and a monomer composition comprising radically polymerizable monomers, and subjecting the monomer composition in the reaction mixture to a radical polymerization to synthesize a dispersed polymer so as to form the polymer dispersion, wherein the ratio of the polymeric dispersant to the dispersed polymer in the polymer dispersion is in a specified narrow range. These polymer dispersions are designated as water-in-water (w/w) polymer dispersions.

Methods for manufacturing a polymer dispersion, polymer dispersions, and their use are provided herein. The methods of manufacturing the polymer dispersion comprise the steps of providing a reaction mixture in an aqueous medium comprising a polymeric dispersant and a monomer composition comprising radically polymerizable monomers, and subjecting the monomer composition in the reaction mixture to a radical polymerization to synthesize a dispersed polymer so as to form the polymer dispersion, wherein the ratio of the polymeric dispersant to the dispersed polymer in the polymer dispersion is in a specified narrow range. These polymer dispersions are designated as water-in-water (w/w) polymer dispersions.

Methods for manufacturing a polymer dispersion, polymer dispersions, and their use are provided herein. The methods of manufacturing the polymer dispersion comprise the steps of providing a reaction mixture in an aqueous medium comprising a polymeric dispersant and a monomer composition comprising radically polymerizable monomers, and subjecting the monomer composition in the reaction mixture to a radical polymerization to synthesize a dispersed polymer so as to form the polymer dispersion, wherein the radical polymerization is performed in presence of a metal scavenger system comprising a metal scavenger and an acid. These polymer dispersions are designated as water-in-water (w/w) polymer dispersions.

Methods for manufacturing a polymer dispersion, polymer dispersions, and their use are provided herein. The methods of manufacturing the polymer dispersion comprise the steps of providing a reaction mixture in an aqueous medium comprising a polymeric dispersant and a monomer composition comprising radically polymerizable monomers, and subjecting the monomer composition in the reaction mixture to a radical polymerization to synthesize a dispersed polymer so as to form the polymer dispersion, wherein the radical polymerization is performed in presence of a metal scavenger system comprising a metal scavenger and an acid. These polymer dispersions are designated as water-in-water (w/w) polymer dispersions.

The present invention relates to a process for preparing an aqueous binder composition, as well as the aqueous binder composition comprising a carboxylic acid-functional vinyl polymer (polymer A) and vinyl polymer (polymer B).

A method for assessing polymeric additive content A in a polymeric particle mixture may comprise determining a concentration B of a metal cation in a polymeric particle mixture comprising parent polymeric particles and polymeric additive particles, wherein the metal cation is selected from alkali earth metals and alkali metals, other than sodium (Na), and the metal cation is capable of forming a water-soluble base; determining a concentration C of the metal cation in the parent polymeric particles; determining a concentration D of the metal cation in the polymeric additive particles; and calculating a polymeric additive content A using formula A=(B−C)/D.

A method for assessing polymeric additive content A in a polymeric particle mixture may comprise determining a concentration B of a metal cation in a polymeric particle mixture comprising parent polymeric particles and polymeric additive particles, wherein the metal cation is selected from alkali earth metals and alkali metals, other than sodium (Na), and the metal cation is capable of forming a water-soluble base; determining a concentration C of the metal cation in the parent polymeric particles; determining a concentration D of the metal cation in the polymeric additive particles; and calculating a polymeric additive content A using formula A=(B−C)/D.

Finely divided, cationic, aqueous polymer dispersion which is obtainable by emulsion polymerisation of ethylenically unsaturated monomers in an aqueous liquid containing a cationic prepolymer as a dispersant, wherein the cationic prepolymer is prepared in the presence of at least one polymerisation initiator by polymerisation of (a) from 15 to 45% by weight of at least one ethylenically unsaturated monomer comprising at least one quaternary ammonium group; (b) from 5 to 80% by weight of at least one optionally substituted styrene; (c) from 0 to 50% by weight of at least one C 1-12 alkyl (meth) acrylate; (d) from 0 to 10% by weight of at least one ethylenically unsaturated monomer comprising an acid group; (e) from 0 to 10% by weight of at least one ethylenically unsaturated monomer comprising an amine group; and (f) from 0 to 20% by weight of at least one non-ionic ethylenically unsaturated monomer differing from (b), (c) and (e), the sum of (a)+(b)+(c)+(d)+(e)+(f) being 100% by weight, in a first emulsion polymerisation in the presence of at least one non-ionic emulsifier, and thereafter, in the aqueous liquid containing the cationic prepolymer a second emulsion polymerisation is carried out, in the presence of at least one polymerisation initiator, of a monomer mixture comprising (i) from 10 to 70% by weight of at least one of an optionally substituted styrene or (meth) acrylonitrile; (ii) from 30 to 90% by weight of at least one CMS alkyl (meth) acrylate; (iii) from 0 to 30% by weight of at least one vinyl ester of linear or branched C.sub.1-30 carboxylic acids; and (iv) from 0 to 30% by weight of at least one non-ionic ethylenically unsaturated monomer differing from (i), (ii) and (iii), the sum of (i)+(ii)+(iii)+(iv) being 100% by weight, and the first emulsion polymerisation and/or the second emulsion polymerisation is optionally carried out in the presence of from 0 to 10% by weight of at least one polymerisation regulator. The polymer dispersions according to the present invention are suitable for use as sizing agents for paper, board and card board.