| Abstract: | A mathematical development interrelating the orientation distribution functions of three kinds of orientation units for a polymer spherulite (i.e., a crystal lamella, a crystallite, and a given reciprocal lattice vector of the crystallite) is formulated on the basis of series expansions of the distribution functions in generalized spherical harmonies. Two types of uniaxial deformation models of a polyethylene spherulite, taking account of micronecking and untwisting of crystal lamellae, and of chain tilting and untwisting of crystal lamellae, respectively, both in addition to affine deformation of the lamellae are discussed. The models are tested by comparison of the theoretical orientation distribution functions of some reciprocal lattice vectors of the crystallite with the results of x-ray diffraction experiments. |
