Product Description-Polyurethane CAS#53504-41-9

Polyurethanes are widely used in water‑based, solvent‑based and hot‑melt adhesives. They may be thermoplastic or reactive, and supplied as one‑component or two‑component systems. Their diverse performance stems from urethane chemistry. Polyurethanes are mostly synthesized by condensation of isocyanates with alcohols, or by polymerizing polyisocyanates with hydroxyl‑rich polyols such as polyesters and polyethers.

Major polyurethane products are foams, adhesives, coatings and elastomers.

1. Polyurethane Foams

Produced from diisocyanates, polyether/polyester polyols plus catalysts, blowing agents and foam stabilizers to yield flexible or rigid foams. Three foaming technologies are available: prepolymer, semi‑prepolymer and one‑shot processes. Prepolymer and semi‑prepolymer suit small‑scale production; the one‑shot method is for large‑volume output. These thermosetting foams feature oil resistance, cold resistance, thermal insulation and sound‑absorbing properties. They serve as thermal insulators, sound‑proof structural parts, leak‑proof layers, shock‑absorbent packaging, cushioning materials and filter media.

2. Polyurethane Adhesives

Two‑component systems mixing polyisocyanates and hydroxyl‑containing polyesters on‑site. They deliver strong bonding to multiple substrates, with good resistance to water, mineral oil and weathering after curing. They bond metals, glass, plastics and ceramics for construction, machinery and aerospace applications.

3. Polyurethane Coatings

Formulated from various isocyanates matched with polyesters, polyethers and polyols, classified as two‑component or one‑component grades. Two‑component polyether‑based coatings are mixed before use. One‑component types include blocked, oil‑modified and moisture‑curing unsaturated‑polyester variants. Application techniques include dipping, spraying and electrodeposition. Cured coatings offer fine insulation, adhesion, abrasion, oil, water and inorganic‑acid‑vapor resistance, suitable for concrete structures, chemical equipment, aircraft components and furniture.

4. Polyurethane Elastomers

Formulated polyurethanes show rubber‑like elasticity over certain temperature ranges. First synthesized by Bayer AG, they fall into cast, compounded and thermoplastic categories. Combining rubber elasticity and plastic processability, they have outstanding oil resistance, wear resistance, low‑temperature flexibility and anti‑aging performance. End‑uses include automotive bearings, textile high‑speed drive belts, and oil‑field & geological‑exploration cables.