Studies On The Compatibility And Self-stratifying Behavior Between Epoxy Resin And Polyacrylate

Self-stratifying coating is composed of two or more incompatible resins, and can stratify with the evaporation of solvent when applied to substrate, and can form a concentration gradient across the film, which will provide the properties of two or more layers, and the more important thing is that self-stratification of coatings can solve the problem of adhesion between the multi-layers, so it has a comprehensive prospect in coating industry. Because of the complexity of self-stratifying coating itself, there are many problems leaved to be solved both in theory and in practice. In this thesis, epoxy resin of good corrosion resistance and splendid adhesion and acrylic resin of good protection against environment and protective decoration were chosen as systems of self-stratifying coating to do research.Combining the necessary conditions of forming efficient self-stratifying coatings, in this dissertation, the solubility parameters of epoxy resin were firstly determined. Then designed by approximately equal distributing point in triangle graph, a series of polyacrylate were synthesized and the compatibility between epoxy resin and polyacrylate was studied. At that basis, the self-stratifying behavior of these two resins was preliminary investigated.The results of research on the one-dimensional solubility parameter and three-dimensional solubility parameter of epoxy resins show that the change of temperature, concentration and molecular weight has influence on the one-dimensional and three-dimensional solubility parameter: the scope of solubility parameter is enlarged with the increase of temperature or the decrease of concentration and molecular weight.The co-solvent method and optical microscope were used to study the compatibility between the synthesized acrylic resins and epoxy resin, and found that the compatibility can be classified to three kinds from compatible to incompatible. The first kind was compatible and the solution was transparent and not delaminating and the film obtained was uniform and transparent. The second was incompatible and the solution was delaminating and the film was opaque and the degree of phase...