The present invention relates to a vinyl chloride polymer and a production method thereof. More specifically, the present invention provides a vinyl chloride polymer having a polydispersity index of 2.0 to 2.3 and a porosity of 60% or greater and a production method thereof in which a vinyl chloride polymerization seed having a conversion rate of 5-20% is first prepared through preliminary polymerization and then a vinyl chloride monomer is introduced into the vinyl chloride polymerization seed to polymerize (main polymerization) a vinyl chloride polymer.

The present invention pertains to: a batch-type suspension polymerization stirrer for producing polyvinyl chloride; and a batch-type suspension polymerization reactor using same. More specifically, the present invention pertains to a batch-type exothermic reactor for performing vinyl chloride polymerization while controlling the internal temperature of an exothermic reaction chamber. Even more specifically, the present invention pertains to an invention wherein the structure of a reflux condenser among jacket, baffle, and reflux condenser devices responsible for heat removal in a reactor is designed to improve productivity and polymerization efficiency.

The present invention pertains to: a batch-type suspension polymerization stirrer for producing polyvinyl chloride; and a batch-type suspension polymerization reactor using same. More specifically, the present invention pertains to a batch-type exothermic reactor for performing vinyl chloride polymerization while controlling the internal temperature of an exothermic reaction chamber. Even more specifically, the present invention pertains to an invention wherein the structure of a reflux condenser among jacket, baffle, and reflux condenser devices responsible for heat removal in a reactor is designed to improve productivity and polymerization efficiency.

Provided is a thermoplastic resin composition exhibiting both high transmittance and low haze and having excellent transparency and excellent scratch resistance and toughness. The thermoplastic resin composition of the present disclosure contains 50% to 99% by mass of methacrylic resin (A) and 1% to 50% by mass of thermoplastic polyurethane (B), wherein the methacrylic resin (A) contains 80.0% to 99.9% by mass of methacrylate ester monomer unit, 0.1% to 20.0% by mass of vinyl monomer unit containing a vinyl monomer copolymerizable with a methacrylate ester monomer excluding maleic acid and maleic anhydride, and 0% to 4.0% by mass of maleic acid and/or maleic anhydride monomer unit, and the thermoplastic polyurethane (B) has a structural unit derived from polyester polyol and a structural unit derived from isocyanate having an alicyclic ring.

Provided is a thermoplastic resin composition exhibiting both high transmittance and low haze and having excellent transparency and excellent scratch resistance and toughness. The thermoplastic resin composition of the present disclosure contains 50% to 99% by mass of methacrylic resin (A) and 1% to 50% by mass of thermoplastic polyurethane (B), wherein the methacrylic resin (A) contains 80.0% to 99.9% by mass of methacrylate ester monomer unit, 0.1% to 20.0% by mass of vinyl monomer unit containing a vinyl monomer copolymerizable with a methacrylate ester monomer excluding maleic acid and maleic anhydride, and 0% to 4.0% by mass of maleic acid and/or maleic anhydride monomer unit, and the thermoplastic polyurethane (B) has a structural unit derived from polyester polyol and a structural unit derived from isocyanate having an alicyclic ring.

The method produces hollow particles which have a high void ratio, which can reduce the residual amount of a sparingly water-soluble solvent used in the production process, and which are less likely to collapse. The method for producing hollow particles which comprise a shell and a hollow portion and which have a void ratio of 50% or more and 90% or less, wherein a suspension treatment of a mixture liquid containing a polymerizable monomer for shell, a polar resin, a hydrocarbon solvent, a sparingly water-soluble inorganic metal salt as a dispersant, and an aqueous medium is carried out to prepare a suspension in which droplets of a monomer composition containing the polymerizable monomer for shell, the polar resin and the hydrocarbon solvent are dispersed in the aqueous medium; a polymerization reaction of the suspension is carried out; and the hydrocarbon solvent is removed from the obtained hollow particles.

The method produces hollow particles which have a high void ratio, which can reduce the residual amount of a sparingly water-soluble solvent used in the production process, and which are less likely to collapse. The method for producing hollow particles which comprise a shell and a hollow portion and which have a void ratio of 50% or more and 90% or less, wherein a suspension treatment of a mixture liquid containing a polymerizable monomer for shell, a polar resin, a hydrocarbon solvent, a sparingly water-soluble inorganic metal salt as a dispersant, and an aqueous medium is carried out to prepare a suspension in which droplets of a monomer composition containing the polymerizable monomer for shell, the polar resin and the hydrocarbon solvent are dispersed in the aqueous medium; a polymerization reaction of the suspension is carried out; and the hydrocarbon solvent is removed from the obtained hollow particles.

Polymeric systems useful for maintaining particle dispersions for extended periods of time.

Polymeric systems useful for maintaining particle dispersions for extended periods of time.

The present invention relates to a method for preparing a thermoplastic copolymer using monomer droplets, a thermoplastic copolymer prepared therefrom and a thermoplastic resin composition including the same. In the preparation method, monomer droplets including an aromatic vinyl-based monomer are injected after reaching a polymerization conversion ratio of 10% to participate in the reaction after initiating polymerization, and a thermoplastic copolymer having an increased average particle diameter may be prepared in high yield.