The present disclosure discloses a method for preparing high-activity polyphenylene sulfide (PPS) by regulating and controlling a water content in a polymerization process and a high-efficiency polyphenylene sulfide resin prepared thereby. The preparation method includes: carrying out a polycondensation reaction with sodium hydrosulfide and p-dichlorobenzene as raw materials and N-methyl-2-pyrrolidone as a solvent until a conversion rate of the p-dichlorobenzene reaches 97% or above, adding deionized water, reducing the temperature in a reactor to 250-260 C. for heat preservation for 1-3 h, and performing cooling for post-treatment; and calculated with the sodium hydrosulfide as 1.0 mol, a molar amount of the added deionized water is 1.0-2.5 mol. The method for preparing high-activity polyphenylene sulfide disclosed in the present disclosure can be simultaneously realized in a PPS polymerization process, and that is to say, an end-capping reagent is not required to be additionally added to affect the molecular weight and thermal stability of the finally prepared PPS; and activation treatment is also not required to be performed after the PPS resin is prepared to additionally increase the technological process and the production cost.

The present disclosure discloses a method for preparing high-activity polyphenylene sulfide (PPS) by regulating and controlling a water content in a polymerization process and a high-efficiency polyphenylene sulfide resin prepared thereby. The preparation method includes: carrying out a polycondensation reaction with sodium hydrosulfide and p-dichlorobenzene as raw materials and N-methyl-2-pyrrolidone as a solvent until a conversion rate of the p-dichlorobenzene reaches 97% or above, adding deionized water, reducing the temperature in a reactor to 250-260 C. for heat preservation for 1-3 h, and performing cooling for post-treatment; and calculated with the sodium hydrosulfide as 1.0 mol, a molar amount of the added deionized water is 1.0-2.5 mol. The method for preparing high-activity polyphenylene sulfide disclosed in the present disclosure can be simultaneously realized in a PPS polymerization process, and that is to say, an end-capping reagent is not required to be additionally added to affect the molecular weight and thermal stability of the finally prepared PPS; and activation treatment is also not required to be performed after the PPS resin is prepared to additionally increase the technological process and the production cost.

A method for producing a polyarylene sulfide comprising: initiating a polymerization reaction by heating a mixture containing an organic polar solvent, a sulfur source, water, a polyhaloaromatic compound, and an alkali metal hydroxide in the presence of at least one auxiliary agent selected from the group consisting of carboxylates and the like, to form a reaction mixture containing a prepolymer having a conversion rate of a polyhaloaromatic compound of 50 mol % or greater, then a phase separation agent addition step of adding a phase separation agent into the reaction mixture, then continuing the polymerization reaction, and then cooling the reaction mixture, in the cooling step, the coolant being added to the reaction mixture at a temperature that is at least 5 C. higher than a maximum thickening temperature and lower than 250 C., and a cooling rate at the maximum thickening temperature being 2.2 C./min or higher and 3.9 C./min or lower.

A method for producing a polyarylene sulfide comprising: initiating a polymerization reaction by heating a mixture containing an organic polar solvent, a sulfur source, water, a polyhaloaromatic compound, and an alkali metal hydroxide in the presence of at least one auxiliary agent selected from the group consisting of carboxylates and the like, to form a reaction mixture containing a prepolymer having a conversion rate of a polyhaloaromatic compound of 50 mol % or greater, then a phase separation agent addition step of adding a phase separation agent into the reaction mixture, then continuing the polymerization reaction, and then cooling the reaction mixture, in the cooling step, the coolant being added to the reaction mixture at a temperature that is at least 5 C. higher than a maximum thickening temperature and lower than 250 C., and a cooling rate at the maximum thickening temperature being 2.2 C./min or higher and 3.9 C./min or lower.

Provided are a purification method for a polyarylene sulfide (PAS) that can efficiently reduce the amount of a carboxyalkylamino group-containing compound in the PAS by treating the carboxyalkylamino group-containing compound in the PAS under a low pressure without using a strong acid, and a production method for a PAS having a reduced amount of the carboxyalkylamino group-containing compound in the PAS. The purification method for a PAS includes: a step of obtaining a crude PAS-containing mixture by removing a solvent from a crude reaction product containing the PAS obtained by reacting a polyhalo aromatic compound with a sulfidizing agent in an organic polar solvent; a step of bringing the crude PAS mixture into contact with water and an oxygen atom-containing solvent to convert the crude PAS into porous particles; and a step of bringing the obtained porous particles into contact with carbonated water.

Provided are a purification method for a polyarylene sulfide (PAS) that can efficiently reduce the amount of a carboxyalkylamino group-containing compound in the PAS by treating the carboxyalkylamino group-containing compound in the PAS under a low pressure without using a strong acid, and a production method for a PAS having a reduced amount of the carboxyalkylamino group-containing compound in the PAS. The purification method for a PAS includes: a step of obtaining a crude PAS-containing mixture by removing a solvent from a crude reaction product containing the PAS obtained by reacting a polyhalo aromatic compound with a sulfidizing agent in an organic polar solvent; a step of bringing the crude PAS mixture into contact with water and an oxygen atom-containing solvent to convert the crude PAS into porous particles; and a step of bringing the obtained porous particles into contact with carbonated water.

A method for forming a polydisulfide polymer is described. In various implementations, the method includes forming a mixture including one or more thiols, agitating the mixture, precipitating the mixture, and extracting a polydisulfide polymer from the mixture. In various implementations, the polydisulfide polymer has a refractive index of at least 1.7.

A method for forming a polydisulfide polymer is described. In various implementations, the method includes forming a mixture including one or more thiols, agitating the mixture, precipitating the mixture, and extracting a polydisulfide polymer from the mixture. In various implementations, the polydisulfide polymer has a refractive index of at least 1.7.

A method for producing polyarylene sulfide that can have a high melt viscosity while suppressing ultra-fine powder generation. The method for producing polyarylene sulfide includes: (1) preparing a prepared mixture containing an organic polar solvent, a sulfur source, and a dihalo aromatic compound; (2) initiating a polymerization reaction by heating the prepared mixture to produce a prepolymer; (3) adding water as a phase separation agent to a reaction mixture in a reaction system to form a phase-separated state; and (4) continuing the polymerization reaction after phase separation. In the method, when a dihalo aromatic compound conversion ratio is 80 mass % or greater and 93 mass % or less and after the prepolymer reaches a weight average molecular weight of 10000 or greater in the first-stage polymerization step, an aromatic compound having 3 or more halogen atoms bonded to an aromatic ring is added to the reaction mixture.