Preparation And Study On The New Property Of Dicyclopentadiene Dioxide Epoxy (DCPDE) /Polyurethane(PU) Interpenetrating Polymer Networks (IPNs)

Dicyclopentadiene dioxide epoxy (DCPDE) resins is an white solid which is water-resistant and insoluble in most organic solvents. DCPDE resins have capabilities of sustaining greater loads at hyperthermia than other known polycarboxylic acid hardened epoxide resins. DCPDE resin is typically employed to encapsulate microelectronic devices and bear hyperthermal and antisepsis coatings because of its excellent heat,moisture,solvency and chemical resistance,superior electrical and mechanical properties,and good adhesion to many substrates. Additionally,the cycloaliphatic epoxy resins,unlike the aromatic epoxy resins,do not have strong UV chromophore groups. So they are highly resistant to ultraviolet light and more durable for outdoor applications such as electrical insulators.After curing,this multifunctional DCPDE resin provides a densely crosslinked protected layer. However,it has inherent objection,such as it,s relatively brittle,the curing agents of DCPDE resin are not easily attacked by nucleophilic reagent and its curing agents could only be few organic acid or anhydride. All these especially limit the the physical properties of the cured DCPDE resin in industry application.Novel copolymer (CPMI-EMDCPE) and copolymer (NA-DCPD) were firstly synthesized by radical polymeration as curing agents of Dicyclopentadiene dioxide epoxy(DCPDE)/ polyurethane(PU) interpenetrating polymer networks(IPNs) ,which were made of Nadic anhydride (NA),Dicyclopentadiene (DCPD) and N-(p-carboxyphenyl) maleimide (CPMI) monomer and ethylene glycol monodicyclopentenylether (EMDCPE) monomer. Infrared spectral analysis and UV spectral analysis were utilized to characterize the chemical structures of the copolymers and DCPDE/PU IPNs,TGA analythsis was utilized to characterize the thermal stability of the copolymers and DCPDE/PU IPNs. The thermal stability and mechanical properties of resulted coatings were further investigated. The incorporation of copolymers (CPMI-EMDCPE) as curing agent into the polyurethane modified Dicyclopentadiene dioxide epoxy resin obvious increased the thermal stability of PU/DCPDE IPNs. The thermal stability of copolymer (CPMI-EMDCPE) was more excellent than copolymer (NA-DCPD). Copolymer (CPMI-EMDCPE) as curing agent increased the thermal stability of DCPDE/PU IPNs and the mechanical property of the resulted coatings when copolymer (NA-DCPD) did the contrary. The results indicated that the formation of DCPDE/PU IPNs increased the flexibility, traction and strike of resulted coatings according to their nature and percentage concentration.The morphology of the resulted coatings was also investigated. Surface morphology of modified Dicyclopentadiene dioxide epoxy resin investigated by scanning electron microscopy (SEM) showed that modified DCPDE resin exhibited heterogeneous morphology.