X‐ray studies on cellophane¹

Abstract

SynopsisX-Ray diffractograms of cellophane showed a considerable variation in the intensity corresponding to the 101, 107, and 002 planes. Application of generally accepted procedures for estimating crystalline content in cellulosic materials yields varying results for crystallinity in cellophane. It is concluded that such procedures are not applicable to cellophane used in this study. EXPERIMENTALThe present work on cellophane was carried out in connection with an investigation of the dielectric properties of cellulose of various lateral order structures. l v 2 The cellophane samples were obtained from Visking Company, Chicago.Cellophane (regenerated cellulose) used in this study was 3l/4 in. dialysis tubings made from a viscose composition of 7% cellulose by weight, 6%NaOH by weight, and a gamma number of 28.5.3 The cellophane tubings contained 20y0 glycerin by weight, based on total dry weight of glycerin and cellulose. Significantly, the processing included simultaneous drying and stretching (linearly and transversely) of the plasticized gel tubing (neverdried glycerin and cellulose), "said stretching being within the range of 17% to 23% in the transverse direction and 2% to 8% in the longitudinal direction.,13 The chemical analysis of the sample has been reported earlier.2 X-ray Diffractograms of CellophaneThe apparatus and the procedure for obtaining x-ray diffraction patterns have been described previously. The cellophane samples were placed in the holder and mounted in the goniometer. The diffraction intensity was measured from an angle of 20 = 10-26". Any error due to misalignment of the samples in the holder was corrected by testing the samples again by rotating them through 90". Figure 1 gives the diffractogram of cellophane with glycerin plasticizer; Figure 2 shows the diffractogram of water-washed and air-dried cellophane (to remove the plasticizer) ; and Figure 3 shows the water-washed, swollen in 95% monoethylamine and then air-dried cellophane. 2459