A highly divided polyurethane sub-compound formed by the action of a binary or polyvalent isocyanate with a binary or polyvalent hydroxy compound, a diamine or the like.
Polyurethane is a polymer compound containing a -NHCOO- unit in a molecular structure. The unit is formed by reacting an isocyanate group and a hydroxyl group. The reaction formula is as follows:
-N=C=O+HO-→-NH-COO-
Discovery of polyurethane: In the 1930s, Otto Bayer of Germany first synthesized TPU. Around 1950, TPU appeared as a textile finishing agent in Europe, but most of them were solvent-based products for dry coating finishing. In the 1960s, water-based TPU coatings emerged as a result of increased environmental awareness and the introduction of government environmental regulations. After the 1970s, water-based PU coatings developed rapidly, and PU-coated fabrics have been widely used. Since the 1980s, breakthroughs have been made in the research and application of TPU. Compared with foreign countries, domestic research on PU textile finishing agents is relatively late.
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