Structural study of cellophane

Abstract

Fine structural aspects of cellophane have been investigated using X-ray and electron diffraction techniques as well as a kinetic study of the dissolution of cellophane in 0.5 M cupriethylene diamine solution. The X-ray diffraction pattern for cellophane shows a typical cellulose II structure while the electron diffraction pattern highlights a typical cellulose I structure with very weak reflection for a cellulose II type lattice. The kinetics study of cellophane dissolution in cupriethylene diamine confirms the presence of these polymorphic forms of cellulose in cellophane. The paper also reports studies of the X-ray and electron diffraction patterns of cellophane in relation to crystallite size and degradation under electron beam. It is shown that the observed anomaly between the X-ray and electron diffraction patterns of cellophane is a consequence of (i) the larger minimum crystallite size requirement for producing diffraction patterns with X-rays than with the electron beam (ii) the much faster degradation of cellulose II crystallites than that of cellulose I crystallites under the electron beam and (iii) the reduction in the crystallite size of cellulose II in cellophane from that in wood pulp alkali cellulose during the process of regeneration.