Synthesis And Properties Of Two Component High Solid Content Acrylic Resins

Acrylic coatings are widely used in buildings,automobiles and other fields because of their advantages of high fullness and good weather resistance.With the increasing awareness of environmental protection,the requirement of environmental protection in the production and application of coatings has also been raised.The research on the environmental protection modification in the synthesis and application of acrylic coatings has received extensive attention.It is one of the important research fields to reduce VOC during preparation and application and to adopt environmentally friendly solvent system.In this paper,the effects of the ratio of functionalized monomers and glass transition temperature and the properties of cured coatings were studied,aiming at the preparation of acrylic coatings with high solid content and low viscosity.Acrylic resin with high solid content and low viscosity was synthesized by solution polymerization at 105 °C with traditional toluene as solvent.The products were characterized by IR,hydroxyl value,molecular weight and viscosity of polymerization system.The changes of molecular weight and viscosity of the copolymers with different copolymerization compositions were compared.Finally,through the analysis of viscosity,hydroxyl value and glass transition temperature,it can be seen that the viscosity of high solid acrylic resin increases with the increase of monomer content and glass transition temperature.The test results show that the water resistance,chemical resistance,adhesion and the like of the paint film are good.In the further study,it is necessary to take into account the traditional synthesis of high solid acrylic resin solvents,such as toluene,xylene,which will cause human body damage and environmental pollution,but also need to take into account the solvent volatilization rate and solubility in the construction process.The toxicity,volatilization rate,solubility parameter and viscosity of the solvent were analyzed,and the environment-friendly ester mixed solvent was selected to synthesize high solid acrylic resin.As the good solvent of acrylic resin,the ester mixed solvent can not take place the photochemical reaction,and can adjust the suitable volatilization rate and prevent the defects such as hanging flow in the process of film forming.The relationship between viscosity and internal structure M(molecular weight),hydroxyl value and viscosity was discussed,and the viscosity of the system was optimized.When the ratio of butyl acetate to propylene glycol monomethyl ether acetate in mixed solvent is 9:1,the apparent viscosity of polymerization system is the lowest.The properties of the film obtained by crosslinking and curing show that the film has a smooth appearance,strong adhesion,grade 0,heat resistance,water resistance and solvent resistance.