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

Abstract Castor oil—a naturally occurring triglyceride of ricinoleic acid containing a special functionality of —OH group was reacted with hexamethylene diisocyanate to obtain liquid polyurethanes under different stoichiometric conditions varying NCO/OH ratio. These polyurethanes were then individually interpenetrated with n-butyl acrylate and ethylene glycol dimethacrylate as crosslinker by radical polymerization using benzoyl peroxide as initiator. The polyurethane/poly(n-butyl acrylate) interpenetrating polymer networks (IPNs) were obtained as tough films by transfer molding. These IPNs were characterized by their chemical resistance, thermal behavior (TGA, DSC), mechanical properties namely tensile strength, Young' s modulus, elongation at break (%) and Shore A hardness. The morphological behavior was analyzed by scanning electron microscopy and dielectrical properties namely, electrical conductivity (σ), dielectric constant (ε′), dielectric loss (ε″) and loss tangent (tan δ) at different temperature were studied. Key Words: PolyurethanesPoly(n-butyl acrylate)EthyleneglycoldimethacrylateInterpenetratingpolymernetworksscanningelectronmicroscopyMechanical propertiesDielectric properties