Process for producing high-purity polyphenylene sulfide resin

Abstract

The invention discloses a process for synthesizing high-purity polyphenylene sulfide resin. The high-purity polyphenylene sulfide resin is made of p-dichlorobenzene and sodium sulfide with certain crystal water, lithium chloride is used as a solubilizing assistant, and N-methyl-2-pyrrolidone is used as a solvent, so that the high-purity polyphenylene sulfide resin can be synthesized. The process includes that chemical raw materials such as oxygen-free deionized water, the sodium sulfide, the lithium chloride and the NMP (N-methyl-2-pyrrolidone) need to be added in a dehydration system before dehydration technological procedures are carried out, and then the p-dichlorobenzene is added into a synthesis system after heating dehydration is completely carried out on the synthesis system, so that condensation polymerization can be carried out. The process has the advantage that the high-purity polyphenylene sulfide resin synthesized and produced by the aid of the process can be widely applied to the fields of aerospace, electronic machinery, petrochemical engineering, foods, light industry, thermal power generation, cement industry, iron and steel manufacture, environmental protection, textile industry and the like.

Description

technical field [0001] The invention belongs to the field of polyphenylene sulfide high-tech material synthesis Background technique [0002] Linear high-molecular-weight polyphenylene sulfide (PPS) is widely used in aerospace, electronic machinery, petrochemical, food, light industry and other industrial technical fields because of its good chemical and physical properties. countries' attention. US Patent No. 4910294, European Patent No. EP0256757, and U.S. Patent No. 4794164 all describe the process of synthesizing PPS in two steps, but they do not involve the method of adding materials. As for the industrial synthesis process of PPS in China, only the synthesis process and its process condition control method announced by Chinese patent CN971073570, almost all adopt a one-time feeding method in the process of its polymerization reaction. When feeding in this method, the temperature in the kettle must be lowered to below 160°C, and then the kettle is opened to feed, othe...

AI Technical Summary

Problems solved by technology

When feeding in this method, the temperature in the kettle must be lowered to below 160°C, and then the kettle is opened to feed, otherwise, p-dichlorobenzene p-DCB, one of the materials participating in the PPS polymerization reaction, will cause a change in the material ratio due to vaporization escape; Reheating the reaction after adding materials not only affects the success rate of the reaction, but also consumes a lot of energy; the exothermic reaction generated by the synthesis of PPS causes vaporized materials to be produced in the kettle, which increases the pressure of the reactor. Synthesizing under pressure often exhausts and releases the pressure, but the exhaust will take away some materials at the same time, making the ratio of materials unbalanced, resulting in the possibility of reaction failure or small molecular weight

[0003] In Chinese patent applications CN001161407 and 201110066322.2, a process control condition for synthesizing polyphenylene sulfide resin is introduced, except for several conventional temperature and pressure parameters, there is no too much elaboration on the synthesis process control index of polyphenylene sulfide resin

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