Bio-based epoxy/polyurethane interpenetrating polymer networks (IPNs) derived from plant oils with tunable thermal and mechanical properties.

Bio-based interpenetrating polymer networks (IPNs) with tunable thermal and mechanical properties were prepared by bio-based polyurethane (PU) and epoxy resin (EP) derived from plant oils. The cure reaction, dynamic mechanical properties, thermal stability, mechanical performance and morphology of bio-based PU/EP IPNs were characterized by Fourier transform infrared spectroscopy, dynamic mechanical analysis, thermogravimetry, universal test machine and scanning electron microscopy. Dynamic modulus, glass transition temperature, thermal stability and tensile strength of bio-based EP/PU IPNs decreased in the content of soybean oil-based PU prepolymers. However, the damping properties of bio-based EP/PU IPNs increased in the content of soybean oil-based PU prepolymers. The elongation at break of bio-based EP/PU IPNs was greatly higher than that of the plant oil-based EP. The elongation at break of the bio-based EP/PU IPN containing 20% soybean oil-based PU prepolymer was fourfold higher than that of the plant oil-based EP. Soybean oil-based PU prepolymer significantly improved the damping properties and the elongation at break of the plant oil-based EP. By adjusting the mass ratio of the plant oil-based EP to the soybean oil-based PU, the glass transition temperature, damping and mechanical properties of bio-based PU/EP IPNs can be optimized. [ABSTRACT FROM AUTHOR]