Preparation And Properties Of UV Cured Coatings Modified By Rare Earth Terbium Complex

UV curing technology has many advantages including highly efficient,energy-saving,economical,and environmental friendly.Thus,it is widely used in all kinds of fields such as coatings,inks,adhesives,3D printing,photoresist and so on.The rare earth element has excellent characteristics of light,electricity and magnetism.The rare earth polymer composite material can be obtained owning excellent characteristics of the rare earth material and the polymer material at the same time by introducing the rare earth complex into the UV-curable coating material.The work of this research is mainly divided into two parts:the synthesis of rare earth complexes and the preparation of rare earth complex composite UV curing materials.In this paper,we have chose terbium ion with good fluorescence properties to coordinate with organic carboxylic acids,and three kinds of rare earth complexes were synthesized,respectively.The structure and performance of these complexes were tested.Then,a series of rare earth polymer composites were prepared by the method of doping rare earth complexes into the UV curable coatings,and their properties were tested and studied.The work were summarized as follows:?1?The rare earth complex Tb-10-UA was synthesized by using unsaturated long-chain fatty acid 10-Undecenoic acid and terbium oxide as raw materials.The structure was characterized by infrared,elemental analysis,XRD and thermogravimetry.The molecular formula is Tb(C₁₁H₁₉O₂)₃·H₂O.The fluorescence spectrum shows that the complex Tb-10-UA can emit the typical emission peak of terbium ion???.The fluorescence intensity is strong and the chromaticity is pure.The effect of pH and reactant ratio(Tb³⁺/10-UA)on the yield and fluorescence intensity of the rare earth complex Tb-10-UA were investigated,respectively.The results show that when the pH is 6.0,the yield of rare earth complex is the highest and the fluorescence intensity is the strongest.When the reactant ratio is 1:4,the fluorescence intensity is the strongest.Moreover,the thermal stability of the complex Tb-10-UA is superior to that of undecylenic acid.?2?The rare earth complex Tb-ABA was synthesized selecting abietic acid with the structure of hydride phenanthrene and terbium oxide as raw materials.The structure was characterized by infrared,elemental analysis,XRD and thermogravimetry.The molecular formula is Tb(C₂₀H₂₈O₂)₃·H₂O.The fluorescence spectra shows that the complex Tb-ABA can emit the fluorescent characteristic peak of terbium ion with pure color.The effect of pH and reactant ratio(Tb³⁺/ABA)on the yield and fluorescence intensity of the rare earth complexes Tb-ABA were investigated,respectively.The results show that when the pH is 6.0,the yield of rare earth complex is the highest and the fluorescence intensity is the strongest.When the ratio is 1:3,the fluorescence intensity is the strongest.Moreover,the thermal stability of the complex Tb-ABA is superior to that of abietic acid.?3?The rare earth complex Tb-RA was synthesized selecting unsaturated long-chain fatty acid ricinoleic acid and terbium oxide as raw materials.It was characterized by infrared,XRD,thermogravimetry.The result shows the product was successfully synthesized.The fluorescence spectra shows that the complex Tb-RA can emit the fluorescent characteristic peak of terbium ion with pure color.The effect of pH on the yield and fluorescence intensity of the rare earth complex Tb-RA were investigated,respectively.The results showed that when the pH is 7.0,it is benefited for the synthesis of the product and the fluorescence intensity is the highest.Moreover,the thermal stability of the complex Tb-RA is superior to that of ricinoleic acid.?4?In order to obtain film with better comprehensive performance,the type and amount of reactive diluent and the amount of photoinitiator were changed.The best UV-curable coating formulation was found:80%B-369 urethane acrylate,15%reactive diluent TMPTA,5%Photoinitiator 1173.The rare earth complexes synthesized above were separately added to the optimum coating to prepare a series of rare earth polymer coating films.A serious of tests such as scanning electron microscopy,fluorescence analysis,thermogravimetric analysis were ultilized,the results show that the rare earth complexes are uniformly dispersed in the polymer matrix and the compatibility in the UV-curable coating are good.The rare earth polymer coating can emit green fluorescence.With the increase of the content of rare earth complexes,the fluorescence intensity increases.Besides,the thermal stability is also good and the hardness of films are 6H.