This disclosure describes polymerization processes and processes for quenching polymerization reactions using reactive particulates, such as high molecular weight functionalized olefin copolymers, as quenching agents, typically in solution or bulk polymerization processes.

The present invention relates to a vinyl chloride-based polymer composition and a method for producing the same, and more particularly, to a vinyl chloride-based polymer composition including a vinyl chloride-based polymer and a plasticizer, wherein the vinyl chloride-based polymer includes a higher fatty acid having 10 to 18 carbon atoms in an amount of more than 0.05 parts by weight to less than 2.0 parts by weight, based on 100 parts by weight of the vinyl chloride-based polymer.

A process for preparing water-absorbing polymer beads with high permeability by polymerizing droplets of a monomer solution, comprising monomers bearing acid groups, in a gas phase surrounding the droplets, wherein the monomer solution comprises polyvalent cations and the polymer beads have a mean diameter of at least 150 m.

An object of the present invention is to provide a cross-copolymer having excellent softness and heat resistance which is useful as a thermoplastic elastomer, and provide a method for producing thereof.

The present invention provides a method for producing a cross-copolymer comprising a coordination polymerization step and an anionic polymerization step, the cross-copolymer has a specific structure. The present invention also provides a cross-copolymer having excellent moldability, softness and heat resistance, which can be produced under the producing conditions satisfying that the molecular weight distribution of the copolymer obtained in the coordination polymerization step is in a specific range.

In one aspect, inks for use with a three-dimensional (3D) printing system are described herein. In some embodiments, an ink described herein comprise 10-70 wt. % or 20-40 wt. % of a cyclopolymerizable monomer, based on the total weight of the ink. The cyclopolymerizable monomer comprises an acrylate moiety and an ethenyl or ethynyl moiety, and the -carbon of the acrylate moiety and the -carbon of the ethenyl or ethynyl moiety may have a 1,5-, 1,6-, 1,7-, or 1,8-relationship. Additionally, an ink described herein can have a viscosity of 1600 centipoise (cP) or less at 30 C., or of 500 cP or less at 30 C. and can be used to print a desired 3D article having mechanical properties similar to those of articles formed from thermoplastic materials.

The invention relates to a use of a coating layer on a paper substrate for blocking oxygen transfer through the coated paper substrate, wherein the coating layer on the paper substrate is obtainable by a process, which comprises the steps of (a) providing a paper substrate with a surface, (b) applying onto the surface of the provided paper substrate an aqueous coating mass, and (c) drying of the paper substrate with the applied aqueous coating mass to obtain the coated paper substrate, wherein the aqueous coating mass contains an aqueous dispersion of a copolymer P, which is obtainable by radically initiated emulsion polymerization of at least 40 parts by weight of styrene and 22 to 49 parts by weight of butadiene and optionally other monomers based on the sum total of the parts by weight of all monomers, which is always 100, in the presence of a first degraded starch. It relates further to a coated paper substrate obtainable with a coating mass comprising the aqueous dispersion of the copolymer P and a further saccharide, which is added after the polymerization of the monomers. It relates also to a process for manufacturing the coated paper substrate obtainable with a coating mass comprising the aqueous dispersion of the copolymer P and the further saccharide.

The present disclosure provides a process for producing propylene-based polymer. The process includes contacting, under polymerization conditions in a gas phase polymerization reactor, propylene monomer and optionally one or more comonomers with a Ziegler-Natta catalyst composition. The process includes maintaining the temperature of a reaction zone of the reactor at a temperature from greater than 72 C. to less than or equal to 85 C., and forming a propylene-based polymer having a molecular weight (M.sub.w) greater than 100,000, and a M.sub.z+1/M.sub.z less than 2.20. The resultant propylene-based polymer is advantageous in fiber applications.

A method for producing a (meth)acrylic resin composition, comprising: continuously feeding reaction starting materials to a tank reactor, the reaction starting materials comprising a polymerizable monomer component, a chain transfer agent and a radical polymerization initiator, the polymerizable monomer component comprising 50 to 100% by mass of methyl methacrylate, 0 to 20% by mass of an acrylic acid alkyl ester and 0 to 30% by mass of an additional monomer; conducting bulk polymerization of the polymerizable monomer component at a polymerization conversion ratio of 40 to 70% by mass to obtain a liquid containing a (meth)acrylic resin; continuously feeding the resulting liquid to a vented extruder to separate volatile component from the (meth)acrylic resin; conducting distillation using an atmospheric distillation column to separate the volatile component into a high boiling fraction (C.sub.1) and a low boiling fraction (A.sub.1); and conducting distillation using a vacuum distillation column having a pressure of 50 kPaG to 101 kPaG at the top of the vacuum distillation column to separate the high boiling fraction (C.sub.1) into a high boiling fraction (C.sub.2) and a low boiling fraction (A.sub.2); reusing the low boiling fraction (A.sub.1) and the low boiling fraction (A.sub.2) as part of the reaction starting materials.

A dispersion stabilizer in the present invention contains an aqueous emulsion (a) obtained by dispersing a polymer (A) having an ethylenically unsaturated monomer unit in an aqueous medium, a PVA (B) having a degree of saponification of 65 mol % or more and less than 82 mol % and a viscosity-average degree of polymerization of 250 or more and less than 1500, and a PVA (C) having a degree of saponification of 82 mol % or more and less than 98 mol % and a viscosity-average degree of polymerization of 1500 or more and less than 4000. The dispersion stabilizer contains: 7 to 51 mass % of the polymer (A); 40 to 84 mass % of the PVA (B); and 9 to 53 mass % of the PVA (C), with respect to a total amount of the polymer (A), the PVA (B), and the PVA (C). A vinyl resin satisfying required performance can be obtained using the dispersion stabilizer.

This invention relates to a polymerization process for forming polymer comprising: contacting (typically in a solution or slurry phase), a monomer and a catalyst system in a reaction zone comprising at least one spiral heat exchanger and recovering polymer, wherein the monomer, the catalyst system and the polymer flow through the at least one spiral heat exchanger in a cross-flow direction relative to spirals of the at least one spiral heat exchanger.