The effect of temperature and thermal history on the WAXS pattern of polycarbonate

The effect of annealing on the local structure of glassy polycarbonate

“…The scattering patterns for the as-supplied, quenched and annealed materials are very similar, apart from die nature of the weak peak at s -0.7 ]~-~. It has been shown previously that the area of the peak was reduced at higher temperatures [8]. Extending the work of Saffell and Windle [8] and Turska et al [9] we have monitored this peak as a function of annealing time and temperature.…”

“…It has been shown previously that the area of the peak was reduced at higher temperatures [8]. Extending the work of Saffell and Windle [8] and Turska et al [9] we have monitored this peak as a function of annealing time and temperature. To define the area of the peak, an artificial background was constructed ( fig.…”

“…A radial distribution function analysis [7] failed to detect any differences between quenched and annealed samples, although such techniques may be insensitive to small changes. Other X-ray studies [5,8,9] have revealed some small changes occurring in the scattering pattern with annealing particularly at small scattering vectors. The loss of impact strength which appears to be associated with a change in deformation behaviour from yielding to crazing [10] on annealing is also seen as a consequence of the reduction in free volume [11].…”

“…This paper reports a development of the wide angle X-ray scattering (WAXS) work of Neki and Geil [5] and Saffell and Windle [8] and uses recent analyses of the local structure of polycarbonate and other phenylene based polymers [15,16].…”

Eliminating the small-angle component of the scattering calculated for models

“…The model is a section of a poly(bisphenol A carbonate) chain in zig-zag conformation of overall length 40 A. The experimental scattering pattern from this material exhibits a temperature-sensitive peak at --0.5/k -1 (Saffell & Windle, 1980), which is thought to arise from interferences within a chain. The small cross section of the model chain means that the scattering calculated from (2) (Fig.…”