Experimental investigation on mechanical performance of PVC foam‐based E‐glass isophthalic polyester composites

Abstract

AbstractThe present research paper investigates the chemical, thermal, mechanical, thermo‐mechanical properties, and fractography of sandwich composites made from E‐glass‐reinforced isophthalic polyester with Poly Vinyl Chloride (PVC) foam as a core by hand. These composites are commonly used in marine applications and manufactured by hand lay‐up method. A comparison is made between the properties of the PVC foam polyester sandwich composite with E‐glass layers on both sides (SC1) and the PVC foam isophthalic polyester sandwich composite with double layers of E‐glass on both sides (SC2) in relation to single‐layer E‐glass. Fourier transform infrared (FTIR) spectroscopy is employed to analyze the chemical composition of the composites. Various mechanical properties, including impact strength, flexural strength (FS), fracture toughness, and tensile strength (TS), are evaluated for the fabricated composites. Thermo‐mechanical and thermal properties are examined using dynamic mechanical analysis and thermogravimetric analysis (TGA), respectively. The chemical analysis identifies the unsaturation sites of (CH2)n, carbonyl group CO of the ester group, and the stretching of CH and CH3. The mechanical properties of SC2 composites are observed to be superior to those of SC1 composites. TGA revealed that both SC1 and SC2 composites showcased comparable temperature‐dependent weight loss patterns. Nonetheless, the SC2 composite displayed elevated glass transition temperature values and superior damping properties, as indicated by its higher Tanδ values. Examination of the fractured surfaces using a scanning electron microscopy (SEM) micrograph reveals a honeycomb structure, matrix cracking, and fiber pullout.Highlights Examination of the chemical, thermal, mechanical, and thermo‐mechanical attributes of sandwich composites made from E‐glass‐reinforced isophthalic polyester with PVC foam as the core. Evaluation of the impact of E‐glass layering on the thickness of the composite skin. Analysis of interfacial properties through FTIR techniques. Assessment of mechanical properties like impact strength, FS, fracture toughness, and TS. Investigation of fracture surfaces using SEM.