Oxygen → Tetrahydrophthalic anhydride

Participants

Reaction Steps

3Me--THPA was produced by a combination of replacement and liquid phase aeration method. Thus, the reaction procedure of Example 8 was repeated except that the respective amounts of maleic anhydride, radical polymerization inhibitor p-tert-butylcatechol and auxiliary polymerization inhibitor dilauryl thiodipropionate were melted at 60° C. and the internal atmosphere was replaced with nitrogen gas containing 1 volume % of oxygen. Then, the same oxygen-containing nitrogen gas was introduced into the liquid phase at a rate of 5 ml/min. The procedure gave 164 g of 3Me--THPA. The investigation revealed no gels in the product.

Provenance & Evidence