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Indexed by:期刊论文

Date of Publication:2018-06-01

Journal:PURE AND APPLIED CHEMISTRY

Included Journals:SCIE

Volume:90

Issue:6

Page Number:969-987

ISSN No.:0033-4545

Key Words:a simultaneous SAXS and WAXD measuring instrument; controversial defect; crystal planes parallel to the surface of films; POLYCHAR-25; theta-2 theta scanning

Abstract:Simultaneous rotations of sample and X-ray detected counter are needed to evaluate orientation distribution of crystallites and amorphous chains oriented predominantly parallel to the film surface in addition to exact diffraction peak profiles obtained without the complicated intensity corrections. The rotation mode is known as "theta-2 theta scanning" system (theta: film, 2 theta: counter). The system has been mainly used in research and development institutes. However, such instruments are not produced at present. Recently, small angle X-ray scattering (SAXS) and wide angle X-ray diffraction (WAXD) intensities have been measured by using X-ray beam generated along one direction. The brand name of the instrument is "a simultaneous SAXS and WAXD measuring instrument". The X-ray beam generated by the instrument has surely high luminance providing high degree resolution of peak profiles by diffraction and/or scattering. The sample stage and detector, however, are fixed, since the intensities for SAXS and WAXD are obtained by the digital display of the number of X-ray photons detected on the imaging plate. Such optical system contains controversial defect on evaluating orientation of crystal planes parallel to the surface of films prepared by T-die and inflation methods as well as the exact profile. The imaging plate cannot detect the diffraction intensity from the crystal planes existing in the angle range between incident beam and Bragg angle associated with the diffraction peak position of the individual crystal planes.