Product Name/English Name：cis-1,2,3,6-Tetrahydrophthalic anhydride

English abbreviation：THPA

CAS：935-79-5

Molecular Formula： C₈H₈O₃

Article No.：S1112

Structural Formula：

Product Introduction

THPA is an important chemical product, mainly used as a curing agent for epoxy resins, a modifier for unsaturated polyester resins and alkyd resins, and an important intermediate in the synthesis of pesticides and pharmaceuticals. In addition, THPA can also be applied to Flame retardant.

Application of THPA

Due to the flammability of polymer materials, thermoplastic and thermosetting polymers require the use of flame retardants in many applications. Halogenated compounds are commonly used as flame retardant additives in polymers. However, due to the generation of more smoke and the release of irritating and corrosive gases during combustion, traditional halogen flame retardants pollute the environment and pose a threat to human health, the European Union banned the use of halogen flame retardants in 2006. In existing technology, it has been shown that organic phosphorus compounds can impart flame retardancy to polymers. However, due to their mobility and the fact that some flame retardants are easily soluble in water, the flame retardancy of the material will gradually weaken, and the migrated small molecules are prone to polluting the environment; On the other hand, the processing of polymer materials often requires a high temperature environment above 200℃, where flame retardants often decompose or participate in certain side reactions, resulting in a loss of flame retardancy and also affecting the mechanical properties of the material. Therefore, the CN112442083A patent has developed a phosphorus containing flame retardant with anhydride and its preparation method and application. The structure of the phosphorus containing flame retardant with anhydride is as follows:

Firstly, 1 mol of tetrahydrophthalic anhydride, 1 mol of diethyl phosphite, and 500 mL of glacial acetic acid were added to the reactor and stirred under nitrogen protection at 65℃; Then add 1mmol of platinum catalyst glacial acetic acid solution dropwise to the reactor and continue the reaction for 15 hours; Finally, isolate and purify the product to obtain the target product.

The phosphorus containing flame retardant with anhydride can participate in the polymerization reaction of polymers as a reactive monomer or chain extender. The phosphorus containing groups of the flame retardant exist in the form of chemical bonds in the polymer material, and there is no phenomenon of small molecule precipitation, nor does it dissolve in water and precipitate, achieving permanent flame retardancy.

References

CN112442083A A phosphorus containing flame retardant with anhydride and its preparation method and application.