| With the progress of the times, people environmental protection consciousness unceasing enhance and environmental regulations gradually consummate. The traditional solvent-based coatings because of their high content of VOC do more harm to the environment and cannot have satisfied the needs of people. The development of environmental friendly water-based coatings and water-based resins have become the hot topic. Alkyd resin as a good overall performance, a wide range of raw materials, not dependent on oil products, cost-effective, is the largest amount of coating resins in a class.So research of waterbrone alkyd resin and waterbrone alkyd coationg become the focus.First, waterbrone alkyd resin is synthesized.The testing indicated that alkyd shortcomings are obvious, slow drying, low hardness, water resistance, particularly in poor alkali resistance. So alkyd resin must be modified. Alkyd resin is modified by styrene and acrylic acid for its shortcomings and styrene modified waterbrone alkyd resin of quick drying,self drying and environmental friendly is obtained. The hardness,water resistance and alkali resistance of styrene modified water-brone alkyd resin are further enhanced by nano SiO2 and aziridine crosslinker.The main contents are as follows:â‘ Waterbrone alkyd is synthesized with bean oleic acid, pentaerythritol TMP,TMA and so on. The result indicated,when oil length is 60%,K value is 1.01 1.03, excess of alcoho is 7%-15%,the amount of TMA is 5-%7%, the surface drying time of modified alkyd resin could be 150 min and the hard drying time could be 36h in room temperature;film hardness could be 2B;film became white in water in 2h, film disbonding in alkali in 0.5h.â‘¡The basic alkyd resin is was synthesized as the per-polymer modified by styrene. The influence of different oil length, K value, acid value of basic resin,for the modifacation stage and the performance of flim,are studied and the optimal formulation of basic alkyd resin is defined. The result indicated, when the basic resin's oil length is 60%,K value is 1.05,end acid value of basic resin is 22-25mgKOH/g, excess of alcoho is 20%-25%, the basic alkyd resin is appropriate for graft copolymerization of styrene.In the modifacation stage,the influence of the amount of styrene, acrylic acid,maleic anhydride and the dropping way of are studied and monmoers and initiating agent, for the modifacation stage and the performance of flim,are studied.Then the optimal formulation of modifacation stage is defined and the styrene modifined water-brone alkyd resin have a high performance. The result indicated, when the mass fraction of styrene was 35% and the mass fraction of acrylic acid was 6%-7%,the surface drying time of modified alkyd resin could be 30min and the hard drying time could be 15h in room temperature; film hardness could be HB;water resistance is no abnormal in 8h.Waterborne alkyd resin, waterborne styrene-modified alkyd varnish and solvent-based styrene-modified alkyd resin were compared.The experimental results showed that the film of drying time and handness of waterborne styrene-modified alkyd resin had been much improved than alkyd resin,could compare with solvent-based styrene-modified alkyd resin.â‘¢The influence of the amount of nano SiO2 and aziridine crosslinker on the film drying time,hardness,water resistance and alkali resistance are studied. The result indicated, aziridine crosslinker has improved the film hardness,water resistance,alkali resistance and no influence on the film drying time; nano SiO2 has improved the film hardness but reduced transparency and no influence on the film drying time; water resistance,alkali resistance.when the mass fraction of aziridine crosslinker is 4% and the mass fraction of nano SiO2 is 3%, film hardness could be 2H;water resistance in 15days and alkali resistance in 120 hours are no abnormal.
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