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The mechanical properties of blocked polyurethane(PU)/epoxy interpenetrating polymer networks (IPNs) were studied by means of their static and damping properties. The studies of static mechanical properties of IPNs are based on tensile properties, flexural properties, hardness, and impact method. Results show that the tensile strength, flexural strength, tensile modulus, flexural modulus, and hardness of IPNs decreased with increase in blocked PU content. The impact strength of IPNs increased with increase in blocked PU content. It shows that the tensile strength, flexural strength, tensile modulus, and flexural modulus of IPNs increased with filler (CaCO3) content to a maximum value at 5, 10, 20, and 25 phr, respectively, and then decreased. The higher the filler content, the greater the hardness of IPNs and the lower the notched Izod impact strength of IPNs. The glass transition temperatures (Tg) of IPNs were shifted inwardly compared with those of blocked PU and epoxy, which indicated that the blocked PU/epoxy IPNs showed excellent compatibility. Meanwhile, the Tg was shifted to a higher temperature with increasing filler (CaCO3) content. The dynamic storage modulus (E′) of IPNs increased with increase in epoxy and filler content. The higher the blocked PU content, the greater the swelling ratio of IPNs and the lower the density of IPNs. The higher the filler (CaCO3) content, the greater the density of IPNs, and the lower the swelling ratio of IPNs. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 1826–1832, 2006

This work presents a process developed to manufacture glass fiber-reinforced vinyl ester (VE)/nano-Al2O3 matrix composites by pultrusion method. The matrix prepolymer for pultrusion in this study was prepared from blends of VE, initiator (t-butyl perbenzoate), and nano-Al2O3. The process feasibility and kinetic analysis of the unidirectional glass fiber-reinforced VE/nano-Al2O3 matrix composites by pultrusion have been investigated. From the investigations of the long pot life of VE/nano-Al2O3 matrix, the high reactivity of VE/nano-Al2O3 matrix, and excellent fiber wet-out of VE/nano-Al2O3 matrix and glass fiber, it was found that the VE/nano-Al2O3 matrix showed excellent process feasibility for pultrusion. A kinetic autocatalytic model, dα/dt = A exp(−E/RT)αm(1 − α)n, was proposed to describe the curing behavior of glass fiber-reinforced VE/nano-Al2O3 matrix composites. Kinetic parameters for the model were obtained from dynamic differential scanning calorimetry scans using a multiple regression technique. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012