Hygrothermal aging of a filled epoxy resin

Abstract

The hygrothermal conditioning of an epoxy resin at 80°C under 80% RH has been followed by weight measurements, thermogravimetric analysis (TGA) and dynamical mechanical analysis (DMA). The samples are either filled with 60% by weight of silica flour or are not filled. Above an apparent saturation value of about 1.5% reached within a few days, a slight but significant mass uptake was observed in the filled resin, especially after 50 days. The TGA showed an evolution of the filled samples with conditioning after 50 days as well, which was not observed on unfilled samples. For the filled samples, the elastic modulus in the rubbery state decreased with conditioning. These evolutions have been attributed to the formation of a degraded inter-phase region due to hydrolysis occurring after the debonding of the filler-matrix interface caused by the absorbed water.

Influence of water ageing on variation in space charge and thermo‐mechanical properties of epoxy micro‐nano composites

“…Also, the mass loss profiles of water aged specimens are shifted towards the left side compared to that of unaged epoxy specimen, indicating that the thermal degradation is occurring in relatively lesser temperatures. The early thermal degradation in case of water aged specimens, could be due to degraded interphase region between the epoxy matrix and filler due to water ageing [36].…”

“…Also, the mass FIGURE 20 Strain distribution along the gauge length of (a) unaged specimen, (b) water aged specimen at RT and (c) water aged specimen at 90 • C FIGURE 21 Elongation in tensile direction (eyy) versus loading time of epoxy composite specimens loss profiles of water aged specimens are shifted towards the left side compared to that of unaged epoxy specimen, indicating that the thermal degradation is occurring in relatively lesser temperatures. The early thermal degradation in case of water aged specimens, could be due to degraded interphase region between the epoxy matrix and filler due to water ageing [36].…”

Dielectric and electrical properties of radiation-cured epoxy

“…Part of the dielectric response might be related to absorbed water. The effect of absorbed water on the properties of epoxy resin has been widely addressed in the literature and is known to induce a serious impact on both the mechanical and electrical properties of the material [9], [10], [11].…”

Fabricação E Caracterização De Materiais Compósitos Resina Epóxi/Fibras De Bucha (Luffa Cylindrica)

“…Observou-se que a imersão nas primeiras horas levou a uma perda de rigidez importante em todos os materiais testados. Os principais mecanismos que levam à degradação física e química de resinas epóxi foram previstos por outros autores [356], [361], [365], [366], [367].…”