Preparation And Properties Of Modified Rosin-based UV-curable Resin

Ultraviolet(UV)curing inks,coatings and adhesives without organic solvent can solve the environmental pollution problems of volatile organic compounds(VOCs),in the future,it will gradually replace the traditional inks,coatings and adhesives containing organic solvent.However,UV curing inks,coatings and adhesives have poor adhesion on non-absorbent substrate(such as polyethylene and polypropylene),which limits their applications.Therefore,the development of a new material with small surface tension,low cost and good adhesion on polyethylene and polypropylene is necessary in UV curing industry.The maleic anhydride(MPA)was prepared through the Diels-Alder reaction,then dimaleopimaric amide acid(DMPAA)was prepared by MPA and aliphatic diamine,FT-IR and ~1HNMR two methods had been used to characterize the structure of intermediates.Next,we studied the effect of experimental conditions such as temperature and time on the output rate of DMPAA,determining the best reaction conditions is that taking N,N-dimethyl formamide as solvent,reaction is under 90?for 8 h,the acid value of target product is 156 mgKOH/g.Next we took the DMPAA as raw materials,methyl glycidyl ester of acrylic(GMA)as modifier,tetrabutyl ammonium bromide as catalyst,hydroquinone and4-methoxy phenol as reaction inhibitor,and toluene as solvent to prepare the modified rosin-based UV curable resin.The reaction conditions were studied and finally we select the appropriate reaction conditions as follows:the quality of catalyst is 3wt%of the quality of DMPAA,the quality of inhibitor dosage is 5wt%of the quality of the GMA,and the reaction is under 110?for 5 h.The application of resin in UV curing system was studied by using the modified resin as the main body reference to relevant national standards.We has carried on the preliminary research and discussion on the properties of the cured film and solution such as the tensile properties of the cured film,adhesion on polypropylene film,coating resistance,thermal stability,resistant glass transition temperature,contact Angle,light curing time,viscosity,surface tension and so on.We took coating flexibility and adhesion as the main index,and through a series of experiments to determine the best formula:butyl acrylate(BA)as the active diluents,resin is at the top of the solubility of diluent,the coating flexibility of resin is well,the hardness of resin was moderate.Moreover,with the increasing proportion of resin content in the system,the glass transition temperature of the film increases continuously,and the adhesion of polypropylene film increases continuously.When the proportion of resin and BA of 1:1,light initiator content is 1wt%,the coating adhesion on polypropylene film can reach a level 0,film hardness as 2 B,tensile strength and elongation at break of 11.9 MPa and 49.3%,curing speed can reach 2.3s,the viscosity of formula is moderate for 151 mPa·s(25?).This resin can be used for printing ink and coating industrial connection as expected.The UV light-curable modified rosin resin was used as the main body,the properties of the emulsions prepared by the relevant national standards were determined,and the properties of the cured films were investigated preliminarily.The results showed that the UV curable modified rosin based resin has good solubility in water with triethylamine as neutralizing agent.the coating have excellent resistance to water.After immersing in 10wt%sodium hydroxide aqueous solution,and 10wt%sulphuric acid solution for 24 h,the cured film did not show massive erosion phenol-menon,the coating adhesion on polypropylene film can reach a level 0-1,the overall performnce is well.The research results of this paper lay a foundation for further application research.