Abstract
The α mechanical loss region of low-density polyethylene has been studied by vibrational and relaxational X-ray diffraction, birefringence, IR dichroism, light-scattering, and dielectric methods. These experiments are consistent with the proposal of Takayanagi that the α1 process is intercrystalline in nature and exhibits an activation energy of about 25 kcal/mole, where the α2 loss is intracrystalline and possesses an activation energy of about 50 kcal/mole.