Entropy and energy effects upon deformation of a rubbery ethylene-octene copolymer

The mechanism of elastic response of a low-crystallinity ethylene-octene co polymer as a representative of the new class of nanoelastomers was consider ed. Based on the analysis of the deformation thermodynamics, intra- and int ermolecular entropy and energy contributions, and temperature coefficients for unperturbed molecular dimensions were determined. It was shown that the region of large deformations is determined by conformational changes in am orphous regions. Intermolecular effects suggest the degradation of the netw ork structure in the beginning of stretching and additional low-order struc turing upon further deformation.