Thermosetting bis(isoimide)-diphenol resin

A thermosetting polymer resin prepared by the reaction of an ethylenically unsaturated bis(isoimide) having the general structure ##STR3## wherein U represents a divalent radical containing a carbon-to-carbon double bond and having from two to twelve carbon atoms, and A represents a divalent radical having from two to thirty carbon atoms, with a dihydric phenol having the general structure

• HO--A'--OH
• wherein A' represents phenylene or substituted derivatives thereof and contains from six to thirty carbon atoms, the molar ratio of said bis(isoimide) to said dihydric phenol being between 50:1 and 1:1 and the reaction temperature being between about 250.degree. F. to about 500.degree. F.