Polyurethane is often referred to as PU or PUR. Polyurethanes are one of the most versatile plastic materials that exist. They can be tailored to be either rigid or flexible and adapt easily to different applications. They can molded into unusual shapes supporting the needs for a range of industrial and consumer products. We use polyurethanes in one form or another every day. Polyurethanes play an important role in making our lives more convenient, and comfortable. Polyurethane is a chemical reaction between polyol and a diisocyanate, both derived from crude oil. Depending on the desired end product, chemical formulations may contain other ingredients such as stabilizers, catalysts, blowing agents or flame retardants. Polyurethanes can be produced in four different forms; elastomers, coatings, flexible foams, and cross-linked foams. Elastomers are materials that can be stretched but will eventually return to their original shape. They are useful in applications that require strength, flexibility, abrasion resistance, and shock absorbing qualities. Polyurethane coatings show a resistance to solvent degradation and have good impact resistance. These coatings are used on surfaces that require abrasion resistance, flexibility, fast curing, adhesion, and chemical resistance such as bowling alleys and dance floors.
Flexible foams are the largest market for polyurethanes. These materials have high impact strength and are used for making most furniture cushioning. Rigid, or cross-linked, polyurethane foams are used to produce insulation in the form of boards or laminate, used in the commercial roofing industry. Buildings are often sprayed with a polyurethane foam.
Because polyurethanes are petrochemical-based polymers, research is being carried out to look for alternatives for recycling polyurethanes after their original life cycle has ended, to avoid it turning into landfill. There are various recycling options, including mechanical, chemical and feedstock recycling.