Methyl tetrahydrophthalic anhydride (MTHPA, MeTHPA
) is used in a wide range of applications. What are the characteristics of methyl tetrahydrophthalic anhydride? What is the scope of the specific use?
Methyl tetrahydrophthalic anhydride (MTHPA, MeTHPA) can be prepared by reacting isoprene and piperylene, the main components of C5, which is a rich and inexpensive ethylene by-product. Therefore, it strengthens the deep processing of C5. Research, using it to produce MTHPA
(MeTHPA), has certain practical significance.
Methyl tetrahydrophthalic anhydride (MTHPA, MeTHPA) is an important intermediate in electronic information materials, pharmaceuticals, pesticides, resins, and the defense industry. 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 epoxy resin cured product using the curing agent has excellent electrical insulation performance and mechanical properties. In recent years, with the continuous improvement of the reliability requirements of insulation performance in the motor, electronics and electrical industries, the application of such curing agents has developed rapidly and has a good market prospect. The annual output of the world is 30,000 tons, the output value exceeds 300 million yuan, and the annual growth rate is 16% to 20%. They are mainly used in high-grade electronic packaging materials for epoxy resins, and can also be used in coatings, plasticizers, pesticides and other industries.
Isomerization reaction 1 to 5 at 130 ° C to 160 ° C in the presence of an acidic isomerization catalyst using solid methyltetrahydrophthalic anhydride (MTHPA, MeTHPA) or crude methyltetrahydrophthalic anhydride
(MTHPA, MeTHPA) formed by the reaction of mixed carbon five with maleic anhydride. In an hour, a weakly basic compound equivalent to an acidic catalyst was further added, and the reaction was continued for 15 to 30 minutes, followed by distillation under reduced pressure to obtain a liquid MTHPA. The key to the technology is to add an appropriate amount of weakly basic compound to the system after the isomerization reaction and before the distillation under reduced pressure to react with the catalyst to form an inert substance, thereby preventing the isomerization reaction and the side reaction from continuing. The quality is improved and the yield is increased.