Preparation method of polyphenylene sulfide resin, and polyphenylene sulfide resin prepared thereby

Patent metadata

Field	Value
Publication number	US-11440996-B2
Application number	US-201816957934-A
Country	US
Kind code	B2
Filing date	Jul 12, 2018
Priority date	Dec 27, 2017
Publication date	Sep 13, 2022
Grant date	Sep 13, 2022

Abstract

A preparation method of a polyphenylene sulfide resin, and a polyphenylene sulfide resin prepared by the method using a sulfur-containing compound, an alkaline substance and p-dichlorobenzene as raw materials, a fatty acid as a polycondensation aid to carry out a polycondensation reaction. After purification treatment, a primary polyphenylene sulfide is obtained, which then reacts with a terminal-group adjusting agent at a high temperature to generate the polyphenylene sulfide resin resulting in high yield and low cost. The prepared polyphenylene sulfide resin has high reactivity, high melting crystallization temperature and excellent thermal stability. The resulting polyphenylene sulfide resin can be directly used for extrusion and injection molding.

First claim

What is claimed is:

1. A method for preparing a polyphenylene sulfide resin, wherein a primary polyphenylene sulfide is used as a raw material, and a hydroxyl-containing aromatic thiol compound and 4-thiophenyl-thiophenol are used as terminal-group adjusting agents to perform a terminal-group adjusting reaction, so as to obtain the polyphenylene sulfide resin, wherein the hydroxyl-containing aromatic thiol compound has a structure of:
HS—Ar—R—OH;

wherein Ar is a phenylene group; and
R is a carbon chain alkylene group or a carbon chain alkylene acyl group, which is selected from a linear structure or a branched structure; and —R—OH and —SH form a para-, meta- or ortho structure on a benzene ring.

2. The method for preparing the polyphenylene sulfide resin according to claim 1 , wherein R is a C1-C4 linear carbon chain alkylene group or carbon chain alkylene acyl group.

3. The method for preparing the polyphenylene sulfide resin according to claim 1 , wherein based on 100 g of the primary polyphenylene sulfide, the hydroxyl-containing aromatic thiol compound is used in an amount of 0.01 to 0.04 mol, and 4-thiophenyl-thiophenol is used in an amount of 0.01 to 0.03 mol.

4. The method for preparing the polyphenylene sulfide resin according to claim 1 , wherein the terminal-group adjusting reaction has a pH of 9 to 12 and a reaction temperature of 250 to 280° C., and wherein a reaction solvent of the terminal-group adjusting reaction is N-methylpyrrolidone.

5. The method for preparing the polyphenylene sulfide resin according to claim 4 , wherein after the terminal-group adjusting reaction is completed, a filtration is performed, a filter cake is washed until a filtrate has a pH of 6 to 8, and the filter cake obtained after washing is dried to obtain a finished polyphenylene sulfide resin.

6. The method for preparing the polyphenylene sulfide resin according to claim 1 , wherein the primary polyphenylene sulfide has a thermal stability index of 0.96 or more.

7. The method for preparing the polyphenylene sulfide resin according to claim 6 , wherein the primary polyphenylene sulfide is obtained by the following method: performing a polycondensation reaction using a sulfur-containing compound and p-dichlorobenzene as raw materials, and separating a reaction solution by cooling, followed by washing and drying, to obtain the primary polyphenylene sulfide.

8. The method for preparing the polyphenylene sulfide resin according to claim 7 , wherein the sulfur-containing compound is a hydrosulfide selected from the group consisting of sodium hydrosulfide, potassium hydrosulfide and mixtures thereof.

9. The method for preparing the polyphenylene sulfide resin according to claim 7 , wherein based on 1.0 mol of total sulfur, p-dichlorobenzene is used in an amount of 1.02 to 1.05 mol.

10. The method for preparing the polyphenylene sulfide resin according to claim 7 , wherein a reaction solvent of the polycondensation reaction is N-methylpyrrolidone, the total amount of the solvent is 5.5 to 6.0 mol based on 1.0 mol of total sulfur, and a reaction system of the polycondensation reaction has a water content of less than 0.5 mol/mol total sulfur.

11. The method for preparing the polyphenylene sulfide resin according to claim 7 , wherein the temperature of the polycondensation reaction is 220 to 280° C.

12. The method for preparing the polyphenylene sulfide resin according to claim 7 , wherein the washing comprises pickling and/or washing with water, and the filter cake is washed until a content of chloride ions remained in the filtrate is 0.01% or less.

13. The method for preparing the polyphenylene sulfide resin according to claim 12 , wherein the pickling step comprises washing the filter cake with an acid selected from the group consisting of hydrochloric acid, sulfuric acid, phosphoric acid and mixtures thereof, wherein the acid is used in an amount of 1.1 to 1.2 mol based on 1.0 mol fatty acid.

14. The method for preparing the polyphenylene sulfide resin according to claim 7 , wherein the polycondensation reaction is carried out in the presence of a polycondensation aid; and the polycondensation aid is an alkaline substance.

15. The method for preparing the polyphenylene sulfide resin according to claim 14 , wherein the alkaline substance is selected from hydroxides of alkali metals; based on 1.0 mol of total sulfur, the alkaline substance is used in an amount of 1.00 to 1.02 mol; the fatty acid is selected from one or more of medium- and short-chain fatty acids; and a molar ratio of the fatty acid to the sulfur-containing compound is 0.8 to 1.0:1.

16. The method for preparing the polyphenylene sulfide resin according to claim 14 , wherein a preparation of the primary polyphenylene sulfide specifically comprises the following steps:
1) adding an alkaline substance and a fatty acid to the solvent to perform a dehydration treatment;
2) adding the sulfur-containing compound to a dehydrated solution obtained in step 1) to perform a secondary dehydration;
3) adding p-dichlorobenzene and conducting a polycondensation reaction to obtain a reaction solution; and
4) separating the reaction solution by cooling, followed by washing and drying, to obtain the primary polyphenylene sulfide.

17. The method for preparing the polyphenylene sulfide resin according to claim 16 , wherein the temperatures for the dehydration and the secondary dehydration in step 1) and step 2) are 180 to 250° C.; and the secondary dehydration is performed until the water content in the reaction system is less than 0.5 mol/mol total sulfur.

18. The method for preparing the polyphenylene sulfide resin according to claim 8 , wherein the sulfur-containing compound is selected from the groups consisting of sodium hydrosulfide, potassium hydrosulfide and mixtures thereof.

19. The method for preparing the polyphenylene sulfide resin according to claim 13 , wherein the pickling step comprises washing the filter cake with hydrochloric acid in an amount of 1.1 to 1.2 mol based on 1.0 mol fatty acid.

20. The method for preparing the polyphenylene sulfide resin according to claim 15 , wherein the alkaline substance is NaOH or KOH; based on 1.0 mol of total sulfur, the alkaline substance is used in an amount of 1.00 to 1.02 mol; and the fatty acid is selected the group consisting of C5-C6 fatty acids; and a molar ratio of the fatty acid to the sulfur-containing compound is 0.8 to 1.0:1.

Assignees

• Zhejiang Nhu Co Ltd
• Univ Zhejiang
• Zhejiang Nhu Special Mat Co Ltd

Inventors

• Li Woyuan
• Yin Hong
• Chen Zhirong
• Hu Baishan
• Zhou Guiyang
• Deng Hangjun
• Lian Ming
• Zhang Xiongwei
• Li Qichuan
• Zhao Jiang

Classifications

• C08G75/0254 Primary

  using metal sulfides · CPC title

• C08L81/02

  Polythioethers; Polythioether-ethers · CPC title

• C08G75/0213 Primary

  containing elements other than carbon, hydrogen or sulfur · CPC title

• C08G75/0259

  metal hydrogensulfides · CPC title

• C08G75/0209

  derived from monomers containing one aromatic ring · CPC title