Synthesis, Modification And Performance Research Of Bio-based Water-based UV Oligomers Based On Itaconic Acid

At present,most of the monomers used to synthesize oligomers of waterborne coatings come from a kind of fossil energy-petroleum.However,these petroleum-based polymer materials have a long degradation period in the natural environment,and some of them are more difficult to degrade.In the long run,they will pollute the soil,water and so on;On the other hand,petroleum energy belongs to primary energy.Since the Industrial Revolution,the global utilization rate of fossil energy such as oil has increased year by year.As far as the coatings industry is concerned,the demand growth rate of oil-based monomers has reached an average of 5.4%per year between 2007 and 2018.According to the current rate of human consumption of fossil energy,some researchers predict that the global fossil energy will be exhausted by 2050.For this reason,green,recyclable biological-based chemical materials have been favored by industry and researchers.Itaconic acid has been rated as one of the top12 potential biological-based chemical materials by the U.S.Department of Energy^[1].The special structure of two-COOH and a double bond enables it to polymerize not only by itself but also with other monomers containing unsaturated double bonds.In addition,this structure can also take place a variety of esterification,addition reactions,Thus it can prepare a variety of new polymer materials^[2].Itaconic acid can be produced by biological effect of colony on waste straw,sugar beet,etc.In this paper,The main studies around itaconic acid and citric acid biomaterials are as follows:1.An all-biological unsaturated oligomer w₁ with branched structure was prepared by using itaconic acid?unsaturated?,citric acid?saturated?and 1,4-butanediol as raw materials.By measuring the acid value to monitor the reaction process,the molecular structure of the synthesized unsaturated polyester was characterized and analyzed by FT-IR.In addition,the obtained resin was watered down and diluted,and the particle size of the waterborne oligomer was determined.The varnish was prepared based on the oligomer.After smearing and curing,the adhesion and thermal stability of the film were tested according to?GB/T 24148-2009?.The results show that the target oligomer is synthesized,and the hardness of the coating pencil is 4H,the flexibility is 4,and the water resistance is good.2.On the basis of₁,in order to improve its comprehensive properties,Using adipic acid or sebacic acid instead of part of citric acid,Two different kinds of UV waterborne all biological base resins were prepared,they are w₂ and w₃.the molecular structure of the synthesized unsaturated polyester was characterized and analyzed by FT-IR.The varnish was prepared based on the oligomer.After smearing and curing,the adhesion and thermal stability of the film were tested according to?GB/T 24148-2009?.meanwhile,Comparison and analysis of thermal stability of coatings containing adipic acid,sebacic acid,and neither acid is introduced,The surface morphology of the coating with and without adipic acid was compared after soaking in water for a certain period of time by electron microscope.3.First,Polyols containing silicon were synthesized by the reaction of DMPA with KH560.Then The compound is used to replace part 1,4-butanediol in the formula in Table2-3,And then react with itaconic acid and citric acid,Finally,A kind of water-borne UV biomarker containing Si was prepared,It is w₄.the molecular structure of the synthesized unsaturated polyester was characterized and analyzed by FT-IR.After smearing and curing,In addition,the particle size of the waterborne oligomer was determined.The varnish was prepared based on the oligomer.After smearing and curing,The adhesion and other properties of the film were tested according to?GB/T 24148-2009?.At the same time,the water contact angle of paint film with different Si content was determined.The results show that:With the introduction of Si,the water resistance of the paint film has been improved,the hydrophobicity has been improved,and it is 108.67°,and the comprehensive properties of the paint film have been improved.