Studies of the structure and water absorption properties of cellulosic materials by infra-red spectroscopy

The work presented in this thesis applies the high resolution derivative technique developed in this laboratory to a study of the structure and water absorption of viscose, dicel and tricel films, prepared in a pure form by techniques develope d during the course of this work. These three materials provide a means of following how progressive acetylation (from 0% in viscose to 88.3% in dicel to 98.3%'in tricel) influences structure and water absorption. A controlled Temperature and Relative Humidity cell was developed to standardize experimental conditions and to enable reproducible spectra to be recorded especially in spectral regions where temperature sensitive hydrogen bonding occurred. The use of the call enabled structural and/or water absorption properties of these materials to be observed by changing the temperature or Relative Humidity at which spectra were recorded; or by observing annealed sample spectra at a standard temperature. Experiments were undertaken to determine the existence of chain folding in viscose, dicel and tricel films. The results of these experiments support the existence of chain folding in viscose and the nature of the fold is discussed in detail. A,T,R, absorption spectra of the film surfaces were recorded in an attempt to study water absorption at surfaces and these spectra were correlated where possible with stereoscan tracings of the surfaces of the films. Evidence is presented from the results of the work in this thesis for the involvement of CH groups in hydrogen bonding.