EPOXY-POLY(2-ETHYLHEXYL ACRYLATE) INTERPENETRATING POLYMER NETWORKS MORPHOLOGY AND MECHANICAL AND THERMAL-PROPERTIES

Full and semi-IPNs of Poly(2-ethylhexyl acrylate), PEHA and crosslinked epoxy homopolymer were prepared and characterized by measurements of mechanical, thermal and morphological properties. Aromatic polyamine adducts and ethylene glycol dimethacrylate were used as the cross-linker for epoxy and comonomer/cross-linker for 2-ethyl hexyl acrylate monomer. Effects of changes of blend ratio on the properties were examined. Semi-IPNs were characterized by higher tensile strength and modulus than the corresponding full IPNs. Both semi- and full IPNs were characterized by broadening of transitions in their respective DSC curves while the weight retention in the thermal decomposition of the IPNs and pseudo-IPNs was higher than the epoxy homopolymer network. Phase separated rubber domains of various sizes are presumed to be responsible for the increased roughness of poly(2-ethyl hexyl acrylate)-modified epoxy which is substantiated by SEM micrographs.