Production of sustainable polyester composite building material using industrial waste plastic core, hemp fabric, and shrimp shell powder: Effect of quasi-isotropic fiber stacking and particle loading

This study investigates the mechanical, fatigue, and creep properties of commercial plywood (6 mm) alternative polyester composite prepared using waste plastic core, hemp fiber, and shrimp shell powder. The primary aim of this research was to develop an exact replacement for plywood building material and study the effect of fiber stacking order as well as the volume fraction of shrimp shell biopolymer on load-bearing and time-dependent properties. Composites' distinct quasi-isotropic stacking orders with varying hemp fiber angles and shrimp filler contents of 0%, 1.0%, and 3.0% were prepared via compression molding and tested based on ASTM standards. Results revealed that the “D” stacking order {(−45/45) + (−30/60) + WPC + (−60/30) + (−45/45)} composite consistently outperformed others, exhibiting superior mechanical strength. Specifically, the D2 composite exhibited elevated strength, including a tensile strength of 168 MPa, flexural strength of 199 MPa, compression strength of 181 MPa, impact energy of 6.23 J, interlaminar shear strength of 25.9 MPa, and v-notch rail shear of 19.7 MPa. The addition of shrimp filler, rich in hydroxyl groups, enhanced intermolecular interactions, contributing to a resilient network and improved fatigue resistance. Moreover, the creep resistance was notably influenced by the quasi-isotropic arrangement, with the “D” designation showcasing optimal performance. Microscopic analysis revealed the critical role of shrimp shell content in promoting cohesion and interlocking fiber structures. The findings underscore the intricate synergy between stacking angles; filler composition and content in achieving robust and eco-friendly polyester composite building material to replace the termite, weather, and water affect commercial plywood.