Described are compositions and methods for inhibiting polymerization of a monomer (e.g., styrene) composition a quinone methide polymerization retarder and an ammonium salt. In a mixture, the ammonium salt improves the efficacy of the quinone methide polymerization retarder and provides greater antipolymerant activity. In turn, the mixture reduces or prevents apparatus fouling and improves the purity of monomer streams.

One embodiment of the present invention relates to a chloroprene copolymer latex, a method for producing a chloroprene copolymer latex, a chloroprene copolymer latex composition, and a molded article or dipped product of a chloroprene copolymer rubber. The chloroprene copolymer latex is a latex of a chloroprene copolymer including monomer units derived from 2-chloro-1,3-butadiene (chloroprene) and monomer units derived from 2-methyl-1,3-butadiene, wherein the tetrahydrofuran insoluble content in the chloroprene copolymer is 20% by mass or less, and the proportion of the monomer units derived from 2-methyl-1,3-butadiene is 10 to 27 mol % in the chloroprene copolymer.

A method for manufacturing a polymer by performing an anionic polymerization reaction by a flow-type reaction, including: introducing a liquid A containing an anionic polymerizable monomer, a liquid B containing an anionic polymerization initiator, and a polymerization terminator into different flow paths respectively and causing the liquids to flow in the respective flow paths; causing the liquid A and the liquid B to join together by using a multilayered cylindrical mixer; subjecting the anionic polymerizable monomer to anionic polymerization while a solution formed by the joining is flowing to downstream in the reaction flow path; and causing a polymerization reaction solution flowing in a reaction flow path and the polymerization terminator to join together such that the polymerization reaction is terminated; and a flow-type reaction system suitable for performing the manufacturing method.

A method for manufacturing a polymer by performing an anionic polymerization reaction by a flow-type reaction, including: introducing a liquid A containing an anionic polymerizable monomer, a liquid B containing an anionic polymerization initiator, and a polymerization terminator into different flow paths respectively and causing the liquids to flow in the respective flow paths; causing the liquid A and the liquid B to join together by using a multilayered cylindrical mixer; subjecting the anionic polymerizable monomer to anionic polymerization while a solution formed by the joining is flowing to downstream in the reaction flow path; and causing a polymerization reaction solution flowing in a reaction flow path and the polymerization terminator to join together such that the polymerization reaction is terminated; and a flow-type reaction system suitable for performing the manufacturing method.

Described are methods and composition for inhibiting polymerization of a monomer (e.g., styrene) composition using an aminated quinone antipolymerant, such as an aminated benzoquinone or aminated naphthoquinone antipolymerant having one or more secondary or tertiary amine group(s). The aminated quinone antipolymerant can be used with little or no nitroxyl group containing antipolymerant yet still provide excellent antipolymerant activity in a monomer-containing composition.

Described are methods and composition for inhibiting polymerization of a monomer (e.g., styrene) composition using an aminated quinone antipolymerant, such as an aminated benzoquinone or aminated naphthoquinone antipolymerant having one or more secondary or tertiary amine group(s). The aminated quinone antipolymerant can be used with little or no nitroxyl group containing antipolymerant yet still provide excellent antipolymerant activity in a monomer-containing composition.

Described are methods and composition for inhibiting polymerization of a monomer (e.g., styrene) composition using an aminated quinone antipolymerant, such as an aminated benzoquinone or aminated naphthoquinone antipolymerant having one or more secondary or tertiary amine group(s). The aminated quinone antipolymerant can be used with little or no nitroxyl group containing antipolymerant yet still provide excellent antipolymerant activity in a monomer-containing composition.

A method for producing polytetrafluoroethylene includes a step of polymerizing tetrafluoroethylene in an aqueous medium in the presence of a hydrocarbon surfactant and a polymerization initiator to obtain polytetrafluoroethylene and a step of adding at least one selected from the group consisting of a radical scavenger and a decomposer of a polymerization initiator after the initiation of polymerization.

A method for producing polytetrafluoroethylene includes a step of polymerizing tetrafluoroethylene in an aqueous medium in the presence of a hydrocarbon surfactant and a polymerization initiator to obtain polytetrafluoroethylene and a step of adding at least one selected from the group consisting of a radical scavenger and a decomposer of a polymerization initiator after the initiation of polymerization.

The present invention provides a composition of a polyethylene glycol maleimide derivative and a polymerization inhibitor. In particular, the present invention provides a composition of an 8-arm polyethylene glycol maleimide derivative and a phenolic polymerization inhibitor. The ingredient and content of the polymerization inhibitor in the composition are reasonably chosen, thereby significantly increasing stability of the polyethylene glycol maleimide derivative, effectively avoiding the undesirable effect of gel solidifying due to polymerization during storage and transportation, and extending a pot life and shelf life of a product thereof.