Cure Characterization of Bismaleimide/Diallyl Bisphenol-A Resin by Fluorescence,UV and FTIR Spectroscopy

摘要

Reaction of 4,4'-bismaleimidodiphenylmethane (BMI) with 0,0-diallyl bisphenol-A(DABPA) results in the formation of a high temperature thermosetting resin. Fluorescence, FT-IR, and UV-Reflection spectroscopic methods have been used to monitor chemical changes which occur during step curing (140 deg C, 200 deg C, and 250 deg C). Fluorescence spectral signals were quenched during the 140 deg C cure cycle. Fluorescence emission and excitation spectra showed increases in intensity during 200 deg C and 250 deg C curing. The fluorescence excitation spectra blue shifted by approximately 22 nm during curing. The conversion of maleimide moieties to succinimide moieties as well as the destruction and reformation of aromatic rings were detected by FT-IR. FT-IR results indicated that Ene and Diels-Alder involved rearomatization. Corroborating evidence for the destruction and reformation of aromatic rings during resin curing was obtained using UV-reflection spectroscopy. The percent reflectance at 295 nm decreased during 140 deg C and 200 deg C curing and then underwent increases during the 250 deg cure cycle. jg.