Glass fiber reinforced rigid polyurethane foams

Rigid polyurethane foam (RPUF)/glass fiber composites have been fabricated from glass fiber, polymeric 4,4′-di-phenylmethane diisocyanate (PMDI) and polypropylene glycols (PPG) using HFC 365mfc as blowing agent. Thermal conductivity, glass transition and decomposition temperatures as well as the mechanical strengths of the foam increased with the addition of glass fiber. This indicates that an optimum fiber content should depend on the balance between the mechanical reinforcement and thermal insulation.The results were interpreted in terms of cell size, closed cell content, density, fiber dispersion and a simple series model for heat transfer of the composite foam.