A polymeric foam is a

foam Foams are materials formed by trapping pockets of gas in a liquid or solid. A bath sponge and the head on a glass of beer are examples of foams. In most foams, the volume of gas is large, with thin films of liquid or solid separating the ...

, in liquid or solidified form, formed from

polymer A polymer (; Greek '' poly-'', "many" + ''-mer'', "part") is a substance or material consisting of very large molecules called macromolecules, composed of many repeating subunits. Due to their broad spectrum of properties, both synthetic a ...

s. Examples include: * Ethylene-vinyl acetate (EVA) foam, the copolymers of ethylene and vinyl acetate; also referred to as polyethylene-vinyl acetate (PEVA) *

Low-density polyethylene Low-density polyethylene (LDPE) is a thermoplastic made from the monomer ethylene. It was the first grade of polyethylene, produced in 1933 by Imperial Chemical Industries (ICI) using a high pressure process via free radical polymerization. Its ...

(LDPE) foam, first grade of polyethylene (PE) *

Nitrile rubber Nitrile rubber, also known as nitrile butadiene rubber, NBR, Buna-N, and acrylonitrile butadiene rubber, is a synthetic rubber derived from acrylonitrile (ACN) and butadiene. Trade names include Perbunan, Nipol, Krynac and Europrene. This rubber i ...

(NBR) foam, the copolymers of acrylonitrile (ACN) and butadiene * Polychloroprene foam or Neoprene * Polyimide foam *

Polypropylene Polypropylene (PP), also known as polypropene, is a thermoplastic polymer used in a wide variety of applications. It is produced via chain-growth polymerization from the monomer propylene. Polypropylene belongs to the group of polyolefins a ...

(PP) foam, including expanded polypropylene (EPP) and polypropylene paper (PPP) * Polystyrene (PS) foam, including expanded polystyrene (EPS), extruded polystyrene foam (XPS) and sometimes polystyrene paper (PSP) **

Styrofoam Styrofoam is a trademarked brand of closed-cell extruded polystyrene foam (XPS), commonly called "Blue Board", manufactured as foam continuous building insulation board used in walls, roofs, and foundations as thermal insulation and water barrie ...

, including extruded polystyrene foam (XPS) and sometimes expanded polystyrene (EPS) *

Polyurethane Polyurethane (; often abbreviated PUR and PU) refers to a class of polymers composed of organic units joined by carbamate (urethane) links. In contrast to other common polymers such as polyethylene and polystyrene, polyurethane is produced from ...

(PU) foam **

LRPu LRPu or low-resilience polyurethane is a material distinguished by an "ability to slowly return to its original shape". The resulting impact resistance results in LRPu being used in soft laptop sleeves and other lightweight cases for portable el ...

low-resilience polyurethane **

Memory foam Memory foam consists mainly of polyurethane with additional chemicals that increase its viscosity and density. It is often referred to as " viscoelastic" polyurethane foam, or low-resilience polyurethane foam ( LRPu). The foam bubbles or ‘cells� ...

Sorbothane Sorbothane is the brand name of a synthetic viscoelastic urethane polymer used as a shock absorber and vibration damper. It is manufactured by Sorbothane, Inc., based in Kent, Ohio. History Sorbothane was invented and patented in 1982 by Dr. Ma ...

*Polyethylene foam, as used in PEF rod * Polyvinyl chloride (PVC) foam **

Closed-cell PVC foamboard Closed-cell PVC foamboard is a lightweight rigid material used primarily in the manufacture of signs and displays. It is considered robust for outdoor use, being immune to rain and resistant to wind and sunlight. History In 1912, the first paten ...

* Silicone foam * Microcellular foam

See also