Degradation of glass fibre/polyester composites after ultraviolet radiation

Glass fabrics and unsaturated polyester resin were selected to fabricate 2, 3 and 5-layer laminates. After ultraviolet (UV) radiation for 20–200 h, laminates were subjected to tensile strength testing. For the 2-layer laminates, after 170-h UV lamp radiation, the tensile strength reduction of the materials became significant. Distinctive degradation was noticed after 200-h UV irradiation for the 3-layer specimens. No evident strength reduction was discovered for the 5-layer samples after 200-h treatment. It is concluded from the research that shot period of UV radiation has no significant influence on the material as far as tensile strength is concerned. Examinations of the fracture surface of the specimen under SEM revealed the deteriorated matrix after extended UV radiation.