Heat Transfer from Gas to Polymer During High Strain Compression

5 Heat Transfer from Gas to Polymer During High Strain Compression 

Mills and Gilchrist (270) analysed the heat transfer that occurs when closed cell foams are subjected to impact, to predict the effect on the uniaxial compression stress-strain curve. Transient heat conduction from the hot compressed gas to the cell walls occurs on the 10 ms 

Compressive stress versus gas volumetric strain curve, for EPP foam of density 43 kg m (254). The loading 

When products are stored in warehouses for long periods, the foam packaging must not creep by more than about 10%, or the impact protection will 

At strains 10%, when the polymer structure has begun to collapse, gas loss, by diffusion through the cell faces of closed cell foams, may contribute to the creep. The effect of this on the creep of LDPE and EVA foams was determined (266). The foam diffusivity for air was predicted from the polymer permeability P and the foam density p using  

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