Method and composition for depolymerization of cured epoxy resin materials

Abstract

A cured epoxy resin material is depolymerized by using a composition including a compound represented by the chemical formula of XOmYn (wherein X is hydrogen, alkali metal or alkaline earth metal, Y is halogen, m is a number satisfying 1≦m≦8 and n is a number satisfying 1≦n≦6), and a reaction solvent, wherein X is capable of being dissociated from XOmYn and Y radical is capable of being produced from XOmYn in the reaction solvent. It is possible to carry out depolymerization of a cured epoxy resin material, for example, at 200° C., specifically 100° C. or lower, and to reduce a processing cost and an energy requirement. It is also possible to substitute for a reaction system using an organic solvent as main solvent, so that the contamination problems caused by the organic solvent functioning as separate contamination source may be solved and environmental contamination or pollution may be minimized.

Description

CROSS-REFERENCE TO RELATED APPLICATION[0001]This application claims the priorities of Korean Patent Application No. 10-2015-0104002, filed on Jul. 22, 2015 and Korean Patent Application No. 10-2016-0030526, filed on Mar. 14, 2016, and all the benefits accruing therefrom under 35 U.S.C. §119, the contents of which in their entirety are herein incorporated by reference.BACKGROUND[0002]1. Field[0003]The present disclosure relates to a method and a composition for depolymerization of cured epoxy resin materials. Particularly, the present disclosure relates to a method for depolymerization of cured epoxy resin materials and a composition used therefor, a method for separating fillers from cured epoxy resin materials, fillers obtained by the method, etc.[0004]2. Description of the Related Art[0005]An epoxy resin is a thermosetting resin including a network polymer formed by ring-opening of epoxy groups generated when mixing an epoxy monomer having two or more epoxy groups in its molecule ...

AI Technical Summary

Benefits of technology

[0024]The present disclosure is directed to providing a method for depolymerization of a cured epoxy resin material, which may allow depolymerization of a cured epoxy resin material at a temperature of 200° C. or lower, specifically 100° C. or lower, in a very simple and rapid manner and reduce a processing cost and an energy requirement, a composition used for the method, and a depolymerized product obtained by the method.

[0025]The present disclosure is also directed to providing a method for depolymerization of a cured epoxy resin material, which may substitute for an organic solvent reaction system using an organic solvent as a main solvent and thus minimize environmental contamination or pollution caused by an organic solvent functioning as separate contamination source, a composition used for the method, and a depolymerization product obtained by the method.

[0026]In addition, the present disclosure is directed to providing a method for depolymerization of a cured epoxy resin material, which may provide increased efficiency of depolymerization of a cured epoxy resin material without using organic solvent reaction system which adopts an organic solvent as a main solvent, a composition used for the method, and a depolymerization product obtained by the method.

[0027]In addition, the present disclosure is directed to providing a method for depolymerization of a cured epoxy resin material, which may allow easy decomposition of a cured epoxy resin material having relatively high difficulty in decomposition, a composition used for the method, and a depolymerization product obtained by the method.

[0028]Further, the present disclosure is directed to providing a method for recovering a filler from a cured epoxy resin material which may prevent degradation of the properties of the filler after decomposing the cured epoxy resin material to provide a recycled filler having excellent properties, and a filler obtained by the method.

[0063]According to example embodiments of the present disclosure, it is possible to carry out depolymerization of a cured epoxy resin material at a temperature of 200° C., specifically 100° C. or lower, and to reduce a processing cost and an energy requirement. It is also possible to substitute for a reaction system using an organic solvent as a main solvent, so that the contamination problems caused by the organic solvent functioning as separate contamination source may be solved and environmental contamination or pollution may be minimized. In addition, it is possible to increase depolymerization efficiency without using a reaction system based on an organic solvent as a main solvent. As well, it is possible to decompose a cured epoxy resin material having relatively high difficulty in decomposition with ease. Further, it is also possible to prevent degradation of properties of a filler recovered after decomposition of the cured epoxy resin material and thus to obtain recycled filler having excellent properties.

Problems solved by technology

Thus, such an epoxy resin advantageously imparts materials with high durability and anticorrosive property, but undesirably has a difficulty in treating and reutilizing the materials after use.

This is significant waste in terms of cost and may cause severe environmental pollution.

However, separation of carbon fibers through a pyrolysis process requires a pretreatment process including preliminarily crushing CFRP mechanically.

When CFRP is crushed to a size of several millimeters, carbon fibers may also be crushed and the carbon fibers to be recycled have a decreased length, which adversely affect the properties of carbon fibers.

In addition, above all, such a pyrolysis process requires a high temperature of 500° C. or higher where organic compounds produce materials, such as dioxin, harmful to the human body due to combustion thereof.

Thus, the above method requires a special processing system capable of resisting such conditions, resulting in poor cost efficiency.

However, in this case, it is not possible to dissolve various cured epoxy resin materials, including cured multi-functional epoxy resin materials or cured epoxy resin materials using an acid anhydride-based curing agent or aromatic diamine-based curing agent.

In addition, a long reaction time and high reaction energy are still required.

Moreover, it is problematic that various organic solvents harmful to the human body are used as main solvents for the reaction system.

Herein, since the organic solvent itself functions as contaminant source, such organic solvent reaction systems have a fundamental limit in that a problem of pollution caused by the organic solvent should be solved.

In addition, such methods according to the related art have low applicability to sparingly decomposable epoxy resins or require a large amount of energy, resulting in unsatisfactory reaction efficiency.

Images