Industry is now attaching great importance to the efficient re-use of production waste and the recycling of consumer durables. The best-established and most widely-used method of recycling flexible foam offcuts is to produce rebonded foams from flakes.
Despite intense efforts to develop alternative technologies such as hydrolysis, glycolysis, adhesive pressing, grinding into powder etc., producing rebonded foam is still the method of material recycling with the greatest technical and economic potential. In Western Europe alone, the volume of foam rebonded in 2006 amounted to approximately 130,000–150,000 tons (conservative estimate) and thus accounts for around 80 % of all material recycling.
Production and cutting waste is shredded into flakes, sprayed with an isocyanate-terminated prepolymer and chemically bound to the required grade of foam (hardness and degree of density) using a superheated steam injection process.
Large blocks of foam are produced during the discontinuous process, as illustrated, and appropriate cutting machinery is used to produce the required elements. Direct production of molded parts is possible and is carried out.
What began as recycling technology has evolved in the past few years into a technology in its own right, with a wide range of products and applications, e.g.: