Chlorinated polyvinyl chloride resin acid-phase method production process

Abstract

The invention discloses a chlorinated polyvinyl chloride resin acid-phase method production process. The working procedures of the production process comprises chlorination, deacidification by filtering, washing by water, neutralizing and drying, reactants of the chlorination procedure comprise the following components in parts by weight: 100 parts of polyvinyl chloride, 500 to 600 parts of hydrochloric acid solution with the mass concentration being 0.1 to 22 percent, 0.2 to 0.4 part of dispersing agent, 0.1 to 0.2 part of emulsifier and 0.1 to 0.3 part of initiator; the operating steps of the chlorination procedure are as follows: (1) adding the dispersing agent, the emulsifier and the polyvinyl chloride into the hydrochloric acid solution, and then stirring for emulsification and dispersion; (2) heating up to 70 to 80 DEG C, adding the initiator, then pumping a chlorine gas into reaction liquid for a chlorination reaction, wherein the reaction temperature is not over 110 DEG C, the pressure is controlled to be not higher than 0.45 MPa, and when the chlorine content reaches needing, the reaction is finished. According to the production process, the chlorination reaction is performed by replacing an aqueous medium with a hydrochloric acid medium with a certain concentration, so that the uniformity of the chlorination reaction is improved, and the chlorine content is stable; meanwhile, after the concentration of acid is increased, acid liquor is recycled, and an assistant in mother liquor is recycled, so that the discharge of waste acid is reduced, the discharge of organic matters is also reduced, the efficiency is improved, the cost is lowered and environment protection is strengthened.

Description

technical field [0001] The invention relates to the technical field of polymer material synthesis, in particular to a chlorinated polyvinyl chloride resin acid phase production process. Background technique [0002] At present, the methods for producing chlorinated polyvinyl chloride resin in China are all water-phase methods. The solvent method has been eliminated due to high production costs. The product quality of the solid-phase method cannot meet the requirements and industrialization cannot be realized. Therefore, the water-phase method is the main production method. The aqueous phase suspension method is to use a certain amount of dispersant to disperse and suspend polyvinyl chloride in pure water, and pressurize chlorine gas under stirring for chlorination. When the required chlorine content is reached, filter and deacidify, wash with water, Neutralized and dried finished product. However, the existing water-phase production process has disadvantages such as low pro...

AI Technical Summary

Problems solved by technology

However, the existing water-phase production process has disadvantages such as low production efficiency, unstable product quality, and large wastewater discharge.