Thickeners are a new type of functional polymer material that has developed rapidly in recent years. They are mainly used to increase the viscosity or consistency of products, and are characterized by small dosage, significant thickening effect, and ease of use. They are widely used in pharmaceuticals, printing and dyeing, cosmetics, food additives, oil extraction, papermaking, and leather processing industries.
Industrial thickeners originated in the 20th century. In 1953, Coodrich introduced the first completely synthetic thickener-polyacrylic acid thickeners-to the market. In the 1960s, sodium polyacrylate began to be used in the food industry abroad. Currently, W/O type polyacrylic acid latex, as an aqueous phase thickener, is widely used in textile printing pastes, dyeing and finishing, and industrial coatings.
In the mid-1970s, my country began research on synthetic thickeners. In recent years, several synthetic thickeners have been successfully developed domestically, most of which are anionic synthetic thickeners, such as the synthetic thickener KG-201 developed by the University of Science and Technology of China and the synthetic thickener PF developed by the Shenyang Chemical Research Institute. Cross-linked polyacrylic acid latex is widely used as a thickener for coatings and printing. However, this type of anionic thickener still has some drawbacks, such as less than ideal electrolyte resistance, thixotropic properties of pigments, and color yield during printing. In the 1980s, polyurethane associative thickeners were developed. Currently, only a few internationally renowned companies such as ICI, DuPont, Sun Chemical, and KYK produce this product, and their production technology is strictly controlled, resulting in monopolistic pricing. Research on waterborne polyurethane thickeners in my country started relatively late. In recent years, domestic companies have imitated foreign products and developed some, but the results have been unsatisfactory, and the products have not been serialized, limiting their application to low-end products.
