Preparation, curing kinetics, and thermal properties of bisphenol fluorene epoxy resin

Diglycidyl ether of 9,9-bis(4-hydroxyphenyl) fluorene (DGEBF) was synthesized to introduce more aromatic structures into an epoxy resin system. The structure of DGEBF was characterized with Fourier transform infrared and H-1-NMR. 4,4'-Diaminodiphenylmethane (DDM) was used as the curing agent for DGEBF, and differential scanning calorimetry was applied to study the curing kinetics. The glass-transition temperature of the cured DGEBF/DDM, determined by dynamic mechanical analysis, was 260 degrees C, which was about 100 degrees C higher than that of widely used diglycidyl ether of bisphenol A (DGEBA). Thermogravimetric analysis was used to study the thermal degradation behavior of the cured DGEBF/DDM system: its onset degradation temperature was 370 degrees C, and at 700 degrees C, its char yield was about 27%, whereas that of cured DGEBA/DDM was only 14%. (C) 2007 Wiley Periodicals, Inc.