Toughening mechanisms in thermoplastic-modified epoxies: 1. Modification using poly(phenylene oxide)
نویسندگان
چکیده
An epoxy based on the diglycidyl ether of bisphenol A (DGEBA) has been modified with poly(phenylene oxide) (PPO) and cured with piperidine. A two-phase alloy resulted, in which the DGEBA epoxy was the continuous phase. Several PPO loadings were investigated. The tensile yield strengths of these PPO-modified epoxies were found to be independent of PPO content. In contrast, the fracture toughness improved with PPO content in a linear fashion. The micromechanical mechanism responsible for the improvement in toughness was found to consist of crack bifurcation and microcracking. Some evidence of particle bridging was also observed, and it is thought that particle bridging may play an important role in the formation of a microcracked damage zone.
منابع مشابه
Toughening mechanisms in elastomer-modified epoxies
The role of matrix ductility on the toughenability and toughening mechanism of elastomermodified, diglycidyl ether of bisphenol A (DGEBA)-based epoxies is investigated. Matrix ductility is varied by using epoxide resins of varying epoxide monomer molecular weights. These epoxide resins are cured using 4,4' diaminodiphenyl sulphone (DDS) and, in some cases, modified with 10vol % carboxyl-termina...
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