Accession Number : AD0657351

Title :   LIGHT SCATTERING BY BANDED SPHERULITES.

Descriptive Note : Technical rept.,

Corporate Author : MASSACHUSETTS UNIV AMHERST POLYMER RESEARCH INST

Personal Author(s) : Clough,S. B. ; van Aartsen,J. J. ; Stein,R. S.

Report Date : MAY 1967

Pagination or Media Count : 55

Abstract : Previous studies (see AD-657 351) of light scattering from banded (or ringed) spherulites are extended to: (1) Two-dimensional spherulites having biaxial crystals with helicoidally varying orientation of their optic axes about the radius. Scattering patterns from such spherulites are calculated and prove to be more complex than corresponding patterns from spherulites containing uniaxial crystals. (2) The scattering from two-dimensional spherulites containing helicoidally oriented uniaxial crystals where the spherulite is affinely deformed. Calculated scattering patterns indicate that the HV scattering maxima resulting from this helicoidal orientation which is initially in the form of symmetrical arcs becomes deformed and displaced with spherulite deformation. (3) The case of banded spherulites with step variation of density or orientation of scattering material. This gives rise to higher order scattering maxima (as are experimentally observed) in contrast to the prediction of the existance of only first order maxima for spherulites with uniformly periodic variation in density or orientation. The predictions are compared with theoretical predictions and experimental results for the scattering from circular gratings. (Author)

Descriptors :   (*POLYMERS, OPTICAL PROPERTIES), (*CRYSTAL STRUCTURE, POLYMERS), LIGHT, SCATTERING, POLARIZATION, DIFFRACTION, CRYSTAL LATTICES, DEFORMATION

Subject Categories : Physical Chemistry
      Plastics
      Electricity and Magnetism
      Optics

Distribution Statement : APPROVED FOR PUBLIC RELEASE