Mechanical characterization of phenolic foams modified by short glass fibers and polyurethane prepolymer

Short glass fibers and polyurethane prepolymer were used to modify phenolic foams. The mechanical properties of the composites were characterized and compared with those of foams unmodified and modified with only polyurethane prepolymer or short glass fibers in terms of friability, compression, and bending properties. It shows that polyurethane prepolymer significantly improved the toughness and reduced the friability of phenolic foams, while short glass fibers markedly increased the compression and bending properties. The compound modified foams exhibited significantly lower friability and higher resistance to cracking behavior than conventional phenolic foams and the foams modified with only short glass fibers, and were much stiffer and stronger than conventional phenolic foams and the foams modified with only polyurethane prepolymer. The compound modified phenolic foams with the 1:3 ratio of short glass fibers to polyurethane prepolymer exhibited excellent integrated mechanical properties. POLYM. COMPOS., 36:1584–1589, 2015. © 2014 Society of Plastics Engineers