Small−angle x−ray−scattering study of microstructure of polyvinylchloride

Abstract

Small-angle x-ray-scattering (SAXS) measurements were made on polyvinylchloride ftlms which were stretched and/or annealed. The SAXS data showed only monotonically decreasing continuous-type scattering which varied according to the time and temperature of thermal treatment and to the amount of ftlm extension. It was concluded from the analysis of these data that annealing and stretching have a relatively small effect on the size of the scattering regions, the major effect being due to the variation in electron density difference between regions. The results were interpreted assuming a two-phase system containing ordered and disordered regions. It was thus concluded that annealing mainly increases the degree of order in those regions which were initially partially ordered, whereas orientation from stretching causes chain alignment and hence partial ordering within the initially disordered regions. This latter conclusion was found to be consistent with the interpretation of the results obtained from infrared dichroism measurements.

Orientation studies of poly(vinyl chloride). Part I: Intrinsic birefringence

“…Their obtained values are in the region of only 0.5% or less. Other studies using SAXS (26,27) concluded that a two-phase structure exists in PVC and that when PVC is annealed above Tg, the ordered structure is enhanced. Ohta, Kajiyama, and Takayanagi (28) used differential scanning calorimetry (DSC) to determine a maximum value of 5.7% crystallity, when PVC is annealed at 130°C.…”

“…The structural order in rigid commercial PVC has been investigated by many with frequent lack of agreement among workers with regard to the nature of the structure (19)(20)(21)(22)(23)(24)(25)(26)(27)(28). In 1956 Natta and Corradini (19) indicated that PVC is a polymer of fairly low degree of crystallinity and of relatively low perfection.…”

Towards a structural characterization of an epoxy based polymer using small-angle x-ray scattering

“…[13][14][15] By varying the incidence angle, samples can be probed on thickness going from atomic scale to few micrometers. Benefiting from the penetration capacity of x rays and the weak absorption of this kind of polymers, the diffuse reflection and the transmission of x radiations will be used in complementarity.…”