Determination of crystallinity in polyethylene by X‐ray diffractometer

Abstract

A convenient and rapid x‐ray diffraction method is described for the determination of per cent crystallinity in polyethylene, using a scanning goniometer with Geiger tube and scaler counter. Results are presented on per cent crystallinities of a number of polyethylenes and on samples made by quenching polyethylene melt at different temperatures in the range of 20–102°C. The samples of polyethylene studied were found to have 65‐71% crystallinity. The temperature at which plyethylene melt is quenched has no appreciable effect on the crystalline content.

X-ray determination of crystallinity and diffuse disorder scattering

“…The characteristic differences in the X-ray diffraction of crystalline and amorphous substances have led to methods (Goppel & Arlmann, 1949;Kast & Flaschner, 1948;NIatthews, Peiser & Richards, 1949;Hermans & Weidinger, 1950;Krimm & Tobolsky, 1951;Aggarwal & Tilley, 1955) which use the intensity relations between the 'crystalline peaks' and the 'amorphous background' or the absolute intensity of one of these to determine the relative amounts of crystalline and amorphous material. These methods imply that the intensity of the 'crystalline peaks' and the 'amorphous background' can be unambiguously correlated with the weight fractions of crystalline and amorphous material.…”

Investigations of surface degradation of high‐density polyethylene materials resulting from tracking, using physicochemical analysis

“…Because the WAXD patterns of the tracking formed zone are formally similar to virgin samples, for brevity, only the virgin HDPE specimen spectrum is shown in Figure 5. Agarwal et al 11 obtained the spectra of polyethylene showing peaks at 21.5 and 23.9°, which are the characteristics of 110 and 220 lattice planes, respectively. Similar characteristic spectra were obtained in the present work, with a shift in peak position of 0.5°.…”

Crystallization behavior of carbon nanofiber/linear low density polyethylene nanocomposites

“…[26][27][28] The degree of crystallinity was found to be 36% 6 2%, 34% 6 2%, 34% 6 3%, and 35% 6 2% for pure LLDPE, PR-19, PR-24, and MJ 1 wt % nanocomposites, respectively. These WAXD-based values are consistent with those obtained from DSC (Table II), and indicate that there was not any appreciable difference in the overall degree of crystallinity with the addition of various CNFs.…”