Hybrid composites from coir fibers reinforced with woven glass fabrics: Physical and mechanical evaluation

Sandwich composites based on coir fiber nonwoven mats as core material were manufactured by Vacuum Assisted Resin Transfer Molding technique. Mechanical and physical properties of produced coir/polyester and coir-glass/polyester composites were assessed. Samples were evaluated according to their reinforcement contents, resin contents, areal density, and thickness. Tests on physical properties revealed that coir-glass/polyester sandwich structure has the lowest values of thickness swelling, water absorption and moisture contents compared with coir/polyester composite. Mechanical tests such as tensile strength, open-hole tensile strength, and flexural strength were also performed on all samples. Coir-glass/polyester sandwich structure showed significant increase in tensile strength of 70 MPa compared with 8 MPa of coir/polyester composite. Introducing two skins of fiber glass woven roving to coir/polyester increased its flexural strength from 31.8 to 131.8 MPa for coir-glass/polyester. POLYM. COMPOS., 38:2212–2220, 2017.