Polyurethane (PU) refers to a polymer whose molecular structure contains urethane groups (-NH-COO-). Urethane is generally produced by the reaction of polyisocyanates (including diisocyanates) with polyols (including diols). Organic polyisocyanates and oligomeric polyols (such as polyethers and polyesters) are the two primary raw materials used in the production of polyurethane, typically accounting for more than 80% of the weight of polyurethane products (excluding solvents). Additives are another key component; although used in small quantities, they are also essential raw materials for polyurethane materials.
There is a wide variety of polyisocyanates and polyols, and an even greater variety of additives.
Based on their functions, additives include catalysts, chain extenders, crosslinking agents (curing agents), flame retardants, blowing agents, foam stabilizers, antioxidants, UV absorbers, hydrolysis inhibitors, biocides (mold inhibitors), coupling agents, primers, antistatic agents, rheological modifiers and additives, leveling agents, wetting and dispersing agents, pigments and color pastes, water-removing agents, modified monomers and resins, and release agents, among others; some of these can be further subdivided into several subcategories.
Polyurethane was invented by German chemist O. Bayer in the 1930s. Due to its flexible formulations, diverse product forms, and excellent performance, its applications across various industries are becoming increasingly widespread.
Polyurethane plays a significant role in the materials industry, and countries around the world are competing to develop their polyurethane resin industries. In recent years, China’s polyurethane materials market has experienced the fastest growth globally, and the share of polyurethane materials within the synthetic resin sector has been steadily increasing. New technologies, raw materials, and processes are constantly emerging, and the variety of products continues to grow year by year.
