Synthesis Of A Comb-like Rapidly UV-cured Polyurethane And Its Film Properties

UV radiation curing is polymerization of UV curing system composed of,unsaturation resin,reactive diluent and various additives under specific wavelength and intensity of UV radiation.All of the componet including the which leading to cross-linked network structure.In this paper,the first aim is to design and synthesize a comb-type UV-curable polyether and a comb-type UV-curable polyurethane;the second aim is to prepare a coating system with the comb-type UV-curing polyurethane as the main resin and research the properties of this coating.Namely the effect of different factors inculding the concentration and species of the initiator,the concentration and species of the active diluent on the properties of the UV curing speed of the unsaturation resin is studied.And then,the optimum rate of the comb-type UV curing resin system was determined.The coating properties of flexibility,hardness,adhesion,UV-cured speed,water resistance,salt tolerance,acid and alkali resistance were characterized which can provide the theoretical basis for the development of UV curing coating technology in the future.In the process of preparing different saturated photosensitive polyether,the different mass ratio of component initial agent to chain extenders is 1:2,1:4,1:6 have been tried to research the properties incluing the curing degree of the unsaturated polyether,viscosity,color and so on.And then,the different curing degree of polyether mix with IPDI(isophorone diisocyanate)to prepare the comb-type UV-curable polyurethane in the presence of metal catalyst.Beside,the properties of comb-type UV-curing polyurethane are also studied incuding the viscosity and color of the light-cured polyurethane.Then the new species of polyurethane was used to prepare the photocurable coating.In this thesis,the effects of photoinitiator 1173,184 and TPO on the UV curing rate were studied.several experiments showed that the photoinitiator TPO emobodies the best UV curing efficiency in the next experiments.And then,in order to choose the best ratio of photoinitiator the different characteristics of TPO in different concentrations and light conditions was also researched.The results showed that considering the curing rate,there exists an optimum cocentration for the the invistigated photoinitiator.The curing rate of the UV-curied resin system increased and compatibility decreased with the concentration of photoinitiator.However,experiments show that UV curing system perform bestly,when the concentration of photoinitiator equaling to 5wt.%.At the same time,physical properties of the terminal hydroxyl unsaturated polyether are as follow: viscosity increases with unsaturation increases;and the color of polyether gradually deepens.Then,the coating was synthesis with different unsaturated polyurethane.The results show that the coating has excellent photocurable properties,and the photocurable rate is less than 2S,and the results show that the coating has the excellent characteristics of UV-cured.Meanwhile,the coating also has excellent adhesion,flexibility,water resistance,acid and alkali performance.