C08F2/32

METHOD FOR PRODUCING HOLLOW RESIN PARTICLES
20230357524 · 2023-11-09 · ·

The method produces hollow resin particles. The method comprising steps of: preparing a mixture liquid comprising (A) a monomer comprising at least one monomer selected from the group consisting of a monovinyl monomer and a hydrophilic monomer excluding acrylonitrile and methacrylonitrile, (B) a crosslinkable monomer, (C) an oil-soluble polymerization initiator, (E) a hydrocarbon solvent, (F) a suspension stabilizer and (G) an aqueous medium; carrying out a suspension treatment of the mixture liquid to prepare a suspension; carrying out a polymerization reaction of the suspension to prepare a precursor composition; carrying out a solid-liquid separation of the precursor composition to obtain the precursor particles; and removing the hydrocarbon solvent (E) included in the precursor particles.

Water-absorbent resin and absorbent article

Provided are a water-absorbent resin easily separable from a recyclable resource in recovering the recyclable resource, and an absorbent article containing an absorbent material containing the water-absorbent resin. The water-absorbent resin according to the present invention has such a structure that a polymer formed from a water-soluble ethylenically unsaturated monomer is crosslinked by using a post-crosslinking agent. The water-absorbent resin has (1) a water-retention capacity for physiological saline of 35 g/g or more, (2) a water-absorption capacity for physiological saline under a load of 4.14 kPa of 10 mL/g or more, (3) an initial gel viscosity of 3000 mPa.Math.s or more, and (4) a gel decomposition index of 0.60 or less: gel decomposition index=B/A wherein A represents an initial gel viscosity (mPa.Math.s), and B represents a gel viscosity after one day (mPa.Math.s).

Temperature-responsive poly(2-hydroxyethyl methacrylate) (PHEMA) and preparation method thereof

Temperature-responsive poly(2-hydroxyethyl methacrylate) (PHEMA) and a preparation method thereof are disclosed. In the preparation method, with a system consisting of benzoyl peroxide (BPO) (an oxidant) and 2-methyl-N-[3-(methyl-phenyl-amino)-propyl]-acrylamide (MPAEMA) or 2-methyl-N-[3-(methyl-phenyl-amino)-propyl]-propionamide (MEMA) (a reducing agent monomer) as a redox initiation system, water and toluene as media, a nonionic surfactant as an emulsifier, and 2-hydroxyethyl methacrylate (HEMA) as a polymerization monomer, polymerization is conducted at room temperature and atmospheric pressure to obtain the PHEMA. An alcohol solution of the PHEMA has an upper critical solution temperature (UCST). The method has the advantages of simple and stable polymerization system, low polymerization cost, easy operation, mild conditions, small impact on the environment, and low energy consumption. Moreover, a molecular weight and UCST of a product are controllable within a specified range.

Temperature-responsive poly(2-hydroxyethyl methacrylate) (PHEMA) and preparation method thereof

Temperature-responsive poly(2-hydroxyethyl methacrylate) (PHEMA) and a preparation method thereof are disclosed. In the preparation method, with a system consisting of benzoyl peroxide (BPO) (an oxidant) and 2-methyl-N-[3-(methyl-phenyl-amino)-propyl]-acrylamide (MPAEMA) or 2-methyl-N-[3-(methyl-phenyl-amino)-propyl]-propionamide (MEMA) (a reducing agent monomer) as a redox initiation system, water and toluene as media, a nonionic surfactant as an emulsifier, and 2-hydroxyethyl methacrylate (HEMA) as a polymerization monomer, polymerization is conducted at room temperature and atmospheric pressure to obtain the PHEMA. An alcohol solution of the PHEMA has an upper critical solution temperature (UCST). The method has the advantages of simple and stable polymerization system, low polymerization cost, easy operation, mild conditions, small impact on the environment, and low energy consumption. Moreover, a molecular weight and UCST of a product are controllable within a specified range.

High-temperature resistant, high-strength, and thixotropic gel plugging agent and its preparation method and application

A high-temperature resistant, high-strength, and thixotropic gel plugging agent is composed of 8-20% of acrylamide monomer, 0.05-0.5% of reactive polymer, 0.1-1.0% of organic polymer cross-linker, 3.0-8.0% of resin toughening agent, 1.0-5.0% of flow pattern regulator, 0.01-0.5% of cross-linking regulator by the weight in the water. The gel solution shows a low apparent viscosity during the shear flow and is easy to be pumped into the wellbore and then into the formation leakage layer; after the pumping stops, the gel solution shows rapidly increased viscosity and strong adhesive force, and form a high-strength barrier between the wellbore and the formation, preventing the drilling fluid from further leaking.

High-temperature resistant, high-strength, and thixotropic gel plugging agent and its preparation method and application

A high-temperature resistant, high-strength, and thixotropic gel plugging agent is composed of 8-20% of acrylamide monomer, 0.05-0.5% of reactive polymer, 0.1-1.0% of organic polymer cross-linker, 3.0-8.0% of resin toughening agent, 1.0-5.0% of flow pattern regulator, 0.01-0.5% of cross-linking regulator by the weight in the water. The gel solution shows a low apparent viscosity during the shear flow and is easy to be pumped into the wellbore and then into the formation leakage layer; after the pumping stops, the gel solution shows rapidly increased viscosity and strong adhesive force, and form a high-strength barrier between the wellbore and the formation, preventing the drilling fluid from further leaking.

MANUFACTURING METHOD FOR INVERSE EMULSION POLYMER
20220081495 · 2022-03-17 ·

A method to manufacture water soluble polymers in inverse (water-in-oil) emulsion with improved performance in oil recovery processes and their use in the treatment of subterranean reservoirs is disclosed.

MANUFACTURING METHOD FOR INVERSE EMULSION POLYMER
20220081495 · 2022-03-17 ·

A method to manufacture water soluble polymers in inverse (water-in-oil) emulsion with improved performance in oil recovery processes and their use in the treatment of subterranean reservoirs is disclosed.

LOW DENSITY POLYVINYL CHLORIDE MICROPARTICLES
20220081545 · 2022-03-17 ·

Hollow microparticles of polyvinyl chloride are disclosed, having low volumetric densities useful for reducing mass per unit volume of polymer or inorganic articles and apparatus having such microparticles compounded into thermoplastic or thermoset polymers. A double emulsion polymerization process is also disclosed as the process to produce the hollow microparticles.