Effects of Hygrothermal Ageing on the Mechanical Properties of Glass-Fibre-Reinforced Polymer Pultruded Profiles

This paper presents the results of an experimental study on the physical and mechanical changes suffered by glass-fibre-reinforced polymer (GFRP) pultruded profiles, made of either unsaturated polyester or vinylester resins, after accelerated hygrothermal ageing. Specimens from both types of profiles, comprising identical fibre contents and architectures, were subjected to: (a) immersion in demineralized water; (b) immersion in saltwater at temperatures of 20, 40 and 60°C for 12 months and; (c) continuous condensation at 40°C for 9 months. Batches of test specimens from both profiles, conditioned in those accelerated exposure environments, were periodically monitored with respect to: (a) mass changes; (b) variation in glass transition temperature evaluated through dynamic mechanical analysis (DMA) and; (c) degradation of mechanical properties, assessed by means of tensile, flexural and interlaminar shear tests.