Foams

Foams are pro­duced with or with­out pres­sure, depend­ing on the process. Foam­ing is achieved by mechan­i­cal or phys­i­cal pro­cess­ing or by a chem­i­cal reac­tion using blow­ing agents. The select­ed process and the raw mate­r­i­al com­po­si­tion of the mate­ri­als have a deci­sive influ­ence on the achiev­able den­si­ty of the foams, as they have an open, closed or mixed cell struc­ture after pro­duc­tion. The pro­cess­ing can be done by extru­sion or injec­tion mold­ing. Pre­fab­ri­cat­ed sheet prod­ucts are often die-cut. 

Com­mon to all foams is the low weight, due to the low den­si­ty. Para­me­ters such as restor­ing force, com­pres­sion set (DVR), water absorp­tion capac­i­ty, acoustic decou­pling, shock absorp­tion, damp­ing and insu­la­tion capac­i­ty some­times dif­fer greatly.