Bisphenol E cyanate ester as a novel resin for repairing BMI/carbon fiber composites: Influence of cure temperature on adhesive bond strength

TitleBisphenol E cyanate ester as a novel resin for repairing BMI/carbon fiber composites: Influence of cure temperature on adhesive bond strength
Publication TypeJournal Article
Year of Publication2013
AuthorsBauer A, Thunga M, Obusek K, Akinc M, Kessler MR
Journal TitlePolymer
Volume54
Pages3994-4002
Date Published07
Type of ArticleArticle
ISBN Number0032-3861
Accession NumberWOS:000321538000026
KeywordsBisphenol E cyanate ester, CONVERSION, glass-transition temperature, Injection repair, kinetics, mechanical-properties, nanocomposites, Polymer matrix composites, POLYMERS
Abstract

The increasing use of polymer matrix composites (PMCs) in structural applications created demand for advanced repair techniques to fix internal delaminations in PMCs. One of a variety of repair techniques is injection repair, which involves injecting a low viscosity resin directly into the damaged area and subsequently curing the resin to heal the damage. In this study, bisphenol E cyanate ester (BECy) was investigated as a potential resin for injection repair of bismaleimide-carbon fiber based composite panels for aircraft. Temperature sensitive repair applications required a technique that avoided the high temperature post-cure of the injection repair resin. Modulated differential scanning calorimetry (MDSC) experiments were used to examine the degree of cross-linking and the glass transition temperature (T-g) of under-cured injection repair resin. The chemistry of cross-linking in under-cured BECy was studied by Fourier transform infrared spectroscopy (FTIR). Lap shear tests of the under-cured injection repair resin on composite substrates revealed the influence of change in isothermal under-cure temperature on the bond strength. Temperature dependent dynamic mechanical analysis disclosed the significance of sub-T-g relaxations on the adhesive properties of the under-cured resin. Post-fracture surface analysis of the lap shear specimens, performed using Scanning Electron Microscope (SEM) micrographs, indicated a mixed mode of fracture in the form of a combination of resin and resin-composite interface failure. (c) 2013 Elsevier Ltd. All rights reserved.

URL<Go to ISI>://WOS:000321538000026
DOI10.1016/j.polymer.2013.05.030