Glass Fiber Reinforced Polyester Syntactic Foam

Abstract

Glass bubbles (GB) have been used as additives in polymer composites to produce light weight syntactic foams. Developments in light weight polyesters have provided an avenue for a class of low density (<1.5 g/cm3) composites. Low density glass fiber (GF) reinforced syntactic polyester (PE) foams were manufactured by incorporating GB into the PE resin paste prior to sheet molding compound (SMC) manufacturing. This study examines the mechanical properties of a syntactic foam composite in comparison to a baseline GF reinforced PE composite. Resin formulations are similar to those used in industrial SMC practice, and are modified with GB to produce syntactic foams. The mechanical properties are characterized by a variety of techniques including tensile testing, flexural testing, and impact testing. The rheological behavior of the PE paste prior to SMC fabrication is also determined. The syntactic foam composites are expected to reduce the density of the final composite without reducing the volume fraction of GF, thereby lowering part mass while maintaining mechanical integrity.