A new recyclable crosslinked polymer combined polyurethane and epoxy resin

Inspired by the nature material, a crosslinked network structure of polyurethane/epoxy resin composite material was built through Diels-Alder (DA) reversible covalent bond reaction between the dienes and dienophile group on the side chain of epoxy resin and polyurethane respectively. The synthesized composite material combined the advantages of polyurethane and epoxy resin. The hard segments of polyurethane and epoxy resin were closely combined through the DA reaction and high density hydrogen bonding. The strength, hardness and toughness of the composite material were greatly enhanced. DA covalent bonds can be reversible with varying the temperature, which led to the heat reprocessing ability of the synthesized composite material. The well-established structure-property relationship shown in this paper could further provide guidance for fabrication of high performance recyclable material with precisely controllable microstructures and behaviors. [Display omitted] •First example combining the polyurethane and epoxy resin blends with containing Diels Alder groups.•Synthesizing the blends based on Diels Alder reaction combining the advantages of polyurethane and epoxy resin.•Structure-property relationship in high performance recyclable material was well-established.