Synthesis And Polymerization Of Urethane Acrylate Monomers

Photocuring technology was a process that transformed a reactive liquid into a solid polymer by radiation.Photopolymerization offers multiple advantages including quick curing,environmental friendly, energy saving,good performances of the curing polymer.A UV-curable resin system is generally composed of oligomer,monomer,photoinitiator, and various additives.Reactive diluents are divided to monofunctional monomers and multifunctional monomers.For the low reactive functional group concentration,the monofunctional monomer has low curing rate.In the current UV industrial processes,urethane(meth)acrylates are made through the reaction of isocyanate and polyols.The hydrogen bond of intermolecular and intramolecular makes the viscosity increase and decrease of the diluent-efficiency.In this thesis monofunctional monomers without hydrogen bond were synthesized though a non-NCO route.Three different monofunctional monomers were synthesized by two-step reaction by using pyrrolideine,piperidine,morpholine,ethylene carbonate and acryloyl chloride.Fourier transform infrared spectra(FTIR) and ~1H NMR spectra were used to identify the structures of monomers. The viscosity of monomers and mixtures of monomer/oligomer, photopolymerization kinetics and dynamic mechanical analyzer(DMA) were investigated as well.The synthesized monomers compared with isobornyl acrylate(IBOA).Results showed that the viscosity of monomer and mixture of monomer/oligomer were both lower than that of IBOA. During photopolymerization the light intensity,the concentration of initiator and different kinds of photoinitiator influenced the kinetics parameters.The DMA analysis showed that monomer/CN964(1/4,w/w) had lower Tg and E' than that of IBOA/CN964(1/4,w/w).