Dielectric evidence for thermal creation of defects in polyethylene crystals

A recent study of the effect of pressure on the dielectric α process in slightly oxidized linear polyethylene showed that the intensity of the process decreases with increasing temperature. This phenomenon was attributed to thermal generation of conformational defects. In the present work a quantitative interpretation of that data is carried out to arrive at defect creation energy parameters. It is found that the creation energy lies in the range of 3–6 kcal/mole and that it has a high degeneracy or statistical weight (in the range 40–800). The statistical weight is interpreted as largely arising from the number of sites in a given crystalline chain for a defect to occur, that is, the number of CH2 units spanning the crystal. It is speculated that kinks are the likely conformational defect.