Foamed polymers mechanical deformation

Cellular Polymers IV. Conference proceedings.. Shawbury, 5th-6th June, 1997, paper 15. 6124 DEFORMATION MECHANISMS EM LDPE CLOSED CELL FOAMS... 

The applicability of the Gibson and Ashby approach, whereby deformation mechanisms are identified, to a range of thermoplastic polymer foams is explored. LDPE, EVA and PP foams were produced by the BXL Plastizote nitrogen expansion process. A full range of mechanical properties is discussed from the simpler aspects of modulus and strength to the complexities of creep and recovery performance. 8 refs. 

Micro-mechanics models for foam deformation are simplifications of the real structure. Figure 4.23 shows a repeating element of the Kelvin foam cell of Fig. 4.22, prior to deformation. The flat surface at the front is a mirror symmetry plane through the polymer structure, as is the hidden flat surface... 

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