Polyurethane (PU)

Polyurethane is a lightweight engineering grade resin with a wide range of densities and applications. It can be processed as a thermoplastic or thermoset plastic. As a rigid foam, PU is used in building insulation because of its light weight, excellent thermal characteristics, and flame resistance. In the form of a rigid integral skin foam, PU is warp free and is easily painted and printed upon, which makes it a popular choice for interior decorating. In the form of a flexible integral skin foam, PU is lightweight and elastic, and can be molded into almost any shape. When cold cured, polyurethane is an elastic foam, which can be molded into an infinite number of shapes and it keeps its shape. These characteristics make PU an excellent choice for seat cushions, padding, etc. In summary, PU has the following physical properties:

  • Low water absorption
  • Excellent adhesion to a wide variety of materials.
  • Excellent flow properties
  • Good flame retardant properties
  • Easily colored and molded
  • Warp free
  • High mechanical strength
  • Light weight
  • Variable hardness


Modern Plastics, January 1997 estimated that U.S. consumption of PU was 4,256 million pounds in 1996. This number is up 5.6 percent from 1995.


Estimates are not available for the amount of PU used as manufacturing feedstock in California. In general, PU could be used in the manufacture of the following commodities:

  • Home and building insulation
  • Sporting equipment
  • Head rests
  • Bicycle seats
  • Packaging material
  • Seat cushioning


  • Society of the Plastics Industry, Inc. (SPI) is a trade association of over 2,000 members representing all segments of the plastics industry in the United States.
  • Society of Plastics Engineers (SPE) is a network of plastics professionals around the world promoting the knowledge and education of plastics and polymers.
  • Vehicle Recycling Partnership (VRP) was formed by the United States Council for Automotive Research (USCAR) to identify and peruse research and development efforts to promote the recycling of motor vehicles. Chrysler, Ford and General Motors formed USCAR to work together on shared technological and environmental concerns.
  • Advanced Recovery is a company involved in recycling scrap materials, specifically dangerous CRTs and electronic equipment.
  • American Plastics Council (APC) is the major national trade association representing the U.S. plastics industry on resource conservation issues.
  • Mat Web is an online materials information resource.

For more information, contact bzassist@calrecycle.ca.gov.