Manufacture of wood fiber reinforced polyvinyl acetate rigid foams

Abstract

In this work, rigid foams designed and manufactured using the freezedrying technique were made from polyvinyl acetate (PVAc), bleached kraft pulp and unbleached kraft pulp. The rigid foams designed as an environmentally-friendly product with no pentane or hydrochlorofluorocarbon included in the manufacturing process. The PVAc based foams were reinforced with different kraft pulp contents. Their performance properties such as compressive and flexural strength, physical and morphological properties were investigated according to relevant standards. The foam densities ranged from 0,017 g/cm3 with %17,65 coefficient of variation (CV) to 0,137 g/cm3 with %2,33 CV. The compression resistance was found between 0,001 N/mm2 with %50,00 CV and 0,03 N/mm2 with %5,98 CV. The flexural resistance was found between 0,005 N/mm2 with %20,00 CV and 0,11 N/mm2 with %6,06 CV. Optimum properties were observed B-4 (PVAc/Bleached Kraft pulp 1/0.8). Bleached kraft pulp reinforcement gave better results on performance characteristics of foam materials compared to unbleached kraft pulp reinforcement. Overall test results showed that the PVAc based rigid foams have promising results.