Polyurethane resins can be classified according to raw materials and structures, reaction mechanisms and molecular structures. First, according to raw materials and structures, they can be divided into polyurethane emulsions, vinyl polyurethane emulsions, polyisocyanate emulsions and blocked polyurethane emulsions. Polyurethane emulsions are prepared from oligomer polyols, chain extenders and diisocyanates; vinyl polyurethane emulsions are two-component systems, formed by mixing vinyl resins and isocyanates; polyisocyanate emulsions are formed by emulsifying polyisocyanates containing hydrophilic groups in water; blocked emulsions contain blocked isocyanate groups, are single-component and stable. Secondly, according to the reaction mechanism, they can be divided into polyurethane emulsions and polyurethane-urea emulsions, the latter of which is formed by chain extension of prepolymers in water. Finally, according to the molecular structure, they can be divided into linear molecular polyurethane emulsions (thermoplastic) and cross-linked polyurethane emulsions (thermosetting), and the cross-linked type can be divided into internal cross-linking and external cross-linking. Polyurethane emulsions are widely used in coatings, adhesives, textiles and leather processing due to their excellent properties.

silicone adhesive products are as follows:Products-IOTA (siliconeadhesives.net)