Polyurethane (PU for short) is a general term for a class of high-molecular polymers whose molecular structure contains carbamate groups (-NHCOO-). It is not a single substance but is made through the addition polymerization reaction of two core raw materials, namely polyols and isocyanates. By adjusting the types, ratios and processes of raw materials, products with completely different properties can be manufactured, and thus it is hailed as the "universal material".
The core characteristic of polyurethane lies in its designability:
1. Diverse forms: It can continuously change from a soft elastic body to a hard rigid body.
2. Excellent performance: It features outstanding wear resistance, high elasticity, oil resistance, aging resistance and insulation.
3. Flexible processing: It can be formed through various processes such as foaming, casting, spraying, and thermoplastic.
Based on its form and performance, polyurethane is mainly classified into the following major categories:
1.Soft foam: such as the filling material for sofas, mattresses and car seats, providing comfortable support.
2. Rigid foam: With excellent heat insulation performance, it is widely used in the insulation of building walls and the insulation layer of refrigerators and cold storage.
3. Elastomers: including wear-resistant tires, shoe soles, conveyor belts, and sports field paving materials (such as plastic running tracks).
4. Coatings, adhesives and sealants: Due to their strong adhesion and corrosion resistance, they are used in industrial protection, furniture coatings and building sealing.
5. Fiber (spandex) : It has excellent elasticity and is a commonly used fabric component for swimsuits, sportswear and underwear.
Since its invention by German scientist Otto Bayer in the 1930s, polyurethane has become an indispensable basic material in modern industry, penetrating into numerous fields such as construction, transportation, home furnishing, electronics, and textiles. Its continuous innovation plays a crucial role in energy conservation, environmental protection, and improving the quality of life.
