No abstract

No abstract

No abstract

Scattering by extruded polyethylene films has been used to analyze in detail the small‐angle scattering of x‐rays by strained spherulitic samples. It is shown that the basic small‐angle patterns in spherulitic specimens can be obtained by summing small‐angle reflections from films drawn both parallel and normal to the direction of extrusion. The representation of a complex pattern by superposition of simpler reflection makes it possible to calculate local strains in various regions of spherulites in bulk specimens.

Polyalkane imides based on 3,3′,4,4′‐diphenyloxidetetracarboxylic, pyromellitic and 1,4,5,8‐naphthalenetetracaboxylic acids, and aliphatic diamines containing 4, 6, 8, 10, or 12 methylene groups have been studied. Relations governing the effect of structure on solubility, heat resistance, density, and crystallizability have been established. Conformation analysis has been carried out and models of the macromolecules have been constructed. The morphology of the crystalline polymers has been studied. For the polymers of the given class, crystallization capability is shown to be associated with the conformational flexibility of the macromolecular unit determining a given acid moiety by the number of methylene groups in the diamine unit.