An imide rings and long aliph. chains-contg. diacid was synthesized in reaction of bicyclo[2,2,2]oct-7-en-2,3,5,6-tetracarboxylic dianhydride and NH2(CH2)(10)COOH and used as modifier of a corn. epoxy resin (epoxy no. 0.49-0.52) cured with NH2(CH2CH2NH)(2)CH2CH2NH2 and tested for mech. (impact and bending strength, hardness) and thermal properties (differential scanning calorimetry, thermogravimetry). Addn. of the diacid resulted in improving the mech. properties of the epoxy resins.