Provided is a polymer production method including: batch-adding a reaction solution including a monomer mixture including a maleimide-based monomer, a vinyl aromatic monomer, and a vinyl cyanide-based monomer and an aqueous solvent to a reactor and initiating polymerization; and carrying out the polymerization while continuously adding the maleimide-based monomer and the aqueous solvent to the reactor, wherein the reaction solution satisfies the above Formula 1.

Provided is a polymer production method including: batch-adding a reaction solution including a monomer mixture including a maleimide-based monomer, a vinyl aromatic monomer, and a vinyl cyanide-based monomer and an aqueous solvent to a reactor and initiating polymerization; and carrying out the polymerization while continuously adding the maleimide-based monomer and the aqueous solvent to the reactor, wherein the reaction solution satisfies the above Formula 1.

Provided is a polymer production method including: batch-adding a reaction solution including a monomer mixture including a maleimide-based monomer, a vinyl aromatic monomer, and a vinyl cyanide-based monomer and an aqueous solvent to a reactor and initiating polymerization; and carrying out the polymerization while continuously adding the maleimide-based monomer and the aqueous solvent to the reactor, wherein the reaction solution satisfies the above Formula 1.

A process comprises polymerizing an olefin monomer in a loop reactor in the presence of a catalyst and a diluent, and producing a slurry comprising solid particulate olefin polymer and diluent. The Biot number is maintained at or below about 3.0 within the loop reactor during the polymerizing process. The slurry in the loop reactor forms a slurry film having a film coefficient along an inner surface of the reactor wall, and the film coefficient is less than about 500 BTU.Math.hr.sup.−1.Math.ft.sup.−2.Math.° F..sup.−1.

A process comprises polymerizing an olefin monomer in a loop reactor in the presence of a catalyst and a diluent, and producing a slurry comprising solid particulate olefin polymer and diluent. The Biot number is maintained at or below about 3.0 within the loop reactor during the polymerizing process. The slurry in the loop reactor forms a slurry film having a film coefficient along an inner surface of the reactor wall, and the film coefficient is less than about 500 BTU.Math.hr.sup.−1.Math.ft.sup.−2.Math.° F..sup.−1.

Provided is a method of suspension polymerization comprising (i) providing a suspension of liquid droplets in an aqueous medium, wherein said droplets comprise (a) one or more water-insoluble vinyl monomers, and (b) a polyelectrolyte (PED) having a polarity, (c) one or more initiators, and wherein said aqueous medium comprises a polyelectrolyte (PEW) having a polarity that is opposite to the polarity of said polyelectrolyte (PED), (ii) polymerizing said vinyl monomer or allowing said vinyl monomer to polymerize.

Provided are hollow particles which are more excellent in heat resistance and dispersibility than ever before and which are lightweight. The hollow particles containing hollow resin particles having a surface covered with inorganic fine particles, wherein a volume average particle diameter of the hollow particles is from 0.1 μm to 9.0 μm, and a void ratio thereof is from 55% to 95%; wherein a repeating unit constituting the resin of the hollow resin particles contains a crosslinkable monomer unit, and a content of the crosslinkable monomer unit is from 25 to 100 parts by mass, with respect to 100 parts by mass of the resin; wherein a primary particle diameter of the inorganic fine particles is from 10 nm to 120 nm; and wherein the inorganic fine particles are contained at from 5 to 180 parts by mass, with respect to 100 parts by mass of the hollow resin particles.

Provided are hollow particles which are more excellent in heat resistance and dispersibility than ever before and which are lightweight. The hollow particles containing hollow resin particles having a surface covered with inorganic fine particles, wherein a volume average particle diameter of the hollow particles is from 0.1 μm to 9.0 μm, and a void ratio thereof is from 55% to 95%; wherein a repeating unit constituting the resin of the hollow resin particles contains a crosslinkable monomer unit, and a content of the crosslinkable monomer unit is from 25 to 100 parts by mass, with respect to 100 parts by mass of the resin; wherein a primary particle diameter of the inorganic fine particles is from 10 nm to 120 nm; and wherein the inorganic fine particles are contained at from 5 to 180 parts by mass, with respect to 100 parts by mass of the hollow resin particles.

Polypropylenes and impact copolymers with low organic volatiles. The impact copolymers comprising a polypropylene and within a range from 5 wt% to 40 wt% of an ethylene-propylene copolymer or rubber, by weight of the impact copolymer; wherein the polypropylene has a melt flow rate within a range from 100 g/10 min to 400 g/10 min, and the impact copolymer has a melt flow rate within a range from 15 g/10 min to 150 g/10 min; and wherein there are less than 1000 .Math.g of oligomer per gram of impact copolymer. The polymers may be made by combining olefins with the reaction product of a solid magnesium compound and a halogen-containing titanium compound with at least one phthalic acid ester compound and at least one diether compound as internal electron donors.

Polypropylenes and impact copolymers with low organic volatiles. The impact copolymers comprising a polypropylene and within a range from 5 wt% to 40 wt% of an ethylene-propylene copolymer or rubber, by weight of the impact copolymer; wherein the polypropylene has a melt flow rate within a range from 100 g/10 min to 400 g/10 min, and the impact copolymer has a melt flow rate within a range from 15 g/10 min to 150 g/10 min; and wherein there are less than 1000 .Math.g of oligomer per gram of impact copolymer. The polymers may be made by combining olefins with the reaction product of a solid magnesium compound and a halogen-containing titanium compound with at least one phthalic acid ester compound and at least one diether compound as internal electron donors.