Interpenetrating Polymer Networks from Castor Oil Based Polyurethanes and Poly(n-Butyl Acrylate)

Castor oil was reacted with diphenyl methane diisocyanate under different experimental conditions and varying NCO/OH ratios to obtain liquid crosslinked polyurethanes. These polyurethanes were then subsequently interpenetrated with n-butyl acrylate monomer and ethylene glycol dimethacrylate as cross linker by radical polymerization using benzoyl peroxide as an initiator. This lead to the formation of novel interpenetrating polymer metworks PPU/PnBA IPNs films by transfer moulding technique. All these IPNs films were characterized by their resistance to chemical reagents, thermal behaviour (TGA), mechanical properties namely tensile strength, Young' s modulus, elongation at break (%) and shore A hardness. The morphology of the IPNs was studied by scanning electron microscopy and dielectric properties namely electrical conductivity ([sgrave]), dielectric constant (e′), dielectric loss (e″) and loss tangent (tan δ) at different temperature were computed.