Damage‐Tolerant Woven Glass Fiber Composites Developed Using Polyvinyl Butyral (PVB) Unsaturated Polyester (UP) Blends

The thermoset matrix is brittle and shows low damage characteristics, and their impact and damage performance can be improved significantly by blending with the thermoplastic matrix. In this way, the properties of both the matrices can be gathered in one composite. This study is focused on the development and optimization of novel blends of unsaturated polyester (UP) resin with polyvinyl butyral (PVB), a thermoplastic polymer, to improve the mechanical properties, especially delamination and impact behavior of associated glass fiber composites. The five blends of UP and PVB were prepared in different concentrations by the solution mixing method. Composite samples of woven glass fabric were fabricated using prepared blends and pure resins as matrices on compression molding. Tensile, flexural, T-peel tests, and the instrumented Charpy impact tests were conducted on the developed samples. A significant improvement in the impact energy absorption (102%) and delamination resistance (110%) was observed for a blend ratio of 40 : 60 and 50 : 50 of PVB : UP, respectively, as compared to pure UP composite samples.