Mechanical behavior of unsaturated polyester toughened epoxy hybrid polymer network reinforced with glass fibre

This research study investigates the effect of unsaturated polyester toughening on mechanical and morphological characteristics of glass fibre reinforced epoxy composites. Here, a polyester/epoxy matrix blend was prepared using an ultrasonicator. Three different epoxy/polyester blended composite specimens (75:25, 50:50 and 25:75) were prepared using the vacuum bag moulding process. The composite samples were evaluated for mechanical properties such as tensile, compression, shear, hardness and impact loadings. The mode-I fracture test is also conducted using a DCB specimen to characterize the inter-laminar fracture behaviour of blended matrix composite specimens. The evaluated results were compared with neat polyester and epoxy composites. The addition of polyester in the epoxy increases the hardness as well as fracture toughness, and it was found to be higher than the neat matrix specimens. But the tensile and compressive response of the blended matrix composites is intermediate between the neat epoxy and polyester composites. The mechanical response of the blended matrix composites degrades when the proportion of the polyester in the blend increases. © 2022