Study On The Application Of A Block Copolymer As Wetting And Dispersing Agent In Coatings

This paper is focused on the application of a new type of block copolymer used as wet and dispersing agent in coatings.The working mechanism of some important types of dispersing agent and its application is reviewed.1.The main types of wetting and dispersing agent,mainly focused on macromolecular type,are reviewed in detail in the light of their structure-property relations.2.According to the above knowledge,the commercial products with best properties is investigated by size exclusion chromatography(SEC) to measure the molecular weight and molecular weight distribution of the products.3.The mechanism and application of living radical polymerization,especially RAFT polymerization,is reviewed on the basis of many previous publications.The chemical structure of super-dispersant is proposed according to the dispersing mechanism.Using a block copolymer of VAc and VEOVA,which is synthesized in our laboratory by a colleague via RAFT polymerization,the possibility to form stable dispersion of different pigment is assessed.4.The application of the block copolymer as wetting and dispersing agent is investigated in great detail.The application properties such as dispersing efficiency, viscosity decreasing,stability,color spread-out property,are measured and discussed according to polymer molecular weight and chemical structure.Although this polymer is found unsuitable for wetting and dispersing agent,we have found its other application possibility and thereby the possible improvement in its structure.