Preparation And Properties Of UV-curable Conductive Waterborne Polyurethane

With the improvement of environmental awareness and national environmental laws and regulations,ordinary coatings can no longer meet people's needs,and special coatings gradually appear in people's field of vision.UV-curing technology has been widely used in the coatings industry because of its advantages of energy saving,environmental protection and high efficiency.As a special coating,conductive coatings are gradually appearing in people's lives.Considering the issues of energy conservation,environmental protection and protection against static electricity,UV-curing conductive coatings have received extensive attention from scientists and become one of the key research topics in the coatings industry.The content of this paper is mainly divided into two parts:In the first part,waterborne polyurethane?WPU?was synthesized by prepolymer method,then DPHA/DPGDA was added to the system to prepare UV-WPU.From the results of FTIR,DPHA/DPGDA was introduced into WPU system,under UV irradiation,the cross-linking curing reaction occurred in C=C of DPHA/DPGDA,which proved that the UV-WPU was successfully prepared.Through the study of the mechanical properties,thermal properties and water resistance of UV-WPU,it was found that when the DPHA/DPGDA content is 40 wt%,the curing time is 60 s,and the photoinitiator 184 is0.16 wt%,UV-WPU has the best mechanical properties and thermal stability,tensile strength up to 21.03 MPa,thermal decomposition temperature Tmax up to 586.31°C;at the same time,UV-WPU has good water resistance,water absorption as low as 3.75%.In the second part,PANI was used as a conductive filler,PANI was dissolved in deionized water,and then blended with UV-WPU emulsion to obtain conductive WPU?UV-C-WPU?by UV curing.The results of FTIR showed that N-H of PANI and C=O of UV-WPU were combined in the form of hydrogen bonds,and UV-C-WPU was successfully prepared.Through the study of UV-C-WPU conductivity and anti-static,it is found that as the PANI content increases,its electrical conductivity increases and the electrostatic half-life decreases.However,studies on the mechanical properties,thermal properties and water resistance of UV-C-WPU have found that as the PANI content increases,the tensile strength gradually decreases,the thermal stability deteriorates,and the water contact angle also decreases.When the PANI content is 10 wt%.the overall performance of UV-C-WPU is the best,the conductivity is 3.56×10^-3 S/cm,the antistatic half-life time is 1.92 s,and the mechanical property is 19.03 MPa.