New process for producing liquid methyl tetrahydro phthalic anhydride

Abstract

The new process of producing liquid methyl tetrahydro phthalic anhydride uses solid methyl tetrahydro phthalic anhydride or coarse methyl tetrahydro phthalic anhydride produced with C5 mixture and maleic anhydride as material and through reaction in the presence of acid isomeric catalyst at 130-060 deg.c for 1-5 hr, further reaction after adding weak alkaline compound in the same equivalent as the acid catalyst for 15-30 min, and decompression distillation to obtain liquid methyl tetrahydro phthalic anhydride. Thus produced liquid methyl tetrahydro phthalic anhydride has high indexes of solidifying point, stability, viscosity, chroma, etc.

Description

technical field

[0001] The invention relates to a new method for producing methyltetrahydrophthalic anhydride, in particular to a new method for producing liquid methyltetrahydrophthalic anhydride. Background technique

[0002] Liquid methyltetrahydrophthalic anhydride is an excellent curing agent for epoxy resin. It has the characteristics of low melting point, low toxicity, low volatility, etc. It is easy to use, has high reactivity with epoxy resin, and has good miscibility. The cured epoxy resin has excellent electrical insulation and mechanical properties. In recent years, with the continuous improvement of the insulation performance and reliability requirements of the motor, electronics, and electrical industries, the application of this type of curing agent has developed rapidly and has a good market prospect. However, compared with similar imported products, domestic liquid methyl tetrahydrophthalic anhydride still has a large gap in quality, mainly reflected in dar...