Recovery method of polycarbonate

Abstract

The invention relates to a recovery method of polycarbonate. The method comprises the following steps: by using a high-dissolving-property solvent as a reaction medium, adding polycarbonate and the solvent into a three-neck flask; after the polycarbonate is completely dissolved, adding a catalyst and an alcoholysis agent into the reaction system to perform alcoholysis reaction; after the reaction finishes, washing the reaction solution, carrying out vacuum filtration and drying to obtain alcoholysis products with different viscosity numbers, which have hydroxy groups at the tail end and have the same structure as the repeated chain link of the polycarbonate; and after the reaction finishes, carrying out washing, vacuum filtration, drying and other after-treatment processes on the reaction system to obtain the alcoholysis product. The recovery method degrades the polycarbonate under mild conditions; different reaction conditions are set to obtain products with different chain links; and both ends of the product are provided with the hydroxy groups, and thus, the product can perform polycondensation reaction with other proper monomers, thereby implementing cyclic utilization of polycarbonate in deed.

Description

technical field [0001] The invention relates to a polycarbonate treatment method, in particular to a polycarbonate recovery method. Background technique [0002] Polycarbonate has outstanding mechanical properties, good heat resistance and cold resistance, and excellent electrical properties, low water absorption, and good light transmission. It is a thermoplastic with excellent comprehensive properties. It is widely used in packaging, electronic appliances, automobile industry, building materials and other fields. With the continuous increase of production and demand, a large amount of waste is produced, because it cannot be degraded in nature, and the existing recycling methods have their own shortcomings. Therefore, it is necessary to find an effective way to recycle polycarbonate waste. . [0003] In the prior art, most polycarbonate recovery methods use monohydric alcohols as alcoholysis agents to recover monomers, and the utilization value of monomers is limited. In...

AI Technical Summary

Problems solved by technology

With the continuous increase of production and demand, a large amount of waste is produced, because it cannot be degraded in nature, and the existing recycling methods have their own shortcomings. Therefore, it is necessary to find an effective way to recycle polycarbonate waste.

[0003] In the prior art, most of the polycarbonate recovery methods use monohydric alcohol as the alcoholysis agent to recover the monomer, and the utilization value of the monomer is limited.

In addition, the defects of traditional polycarbonate degradation, such as low monomer selectivity and many by-products under pyrolysis conditions; harsh requirements for equipment and conditions under supercritical conditions; reactions caused by insolubility of polycarbonate and alcoholysis agent Time extension, etc.