Urška Stankovič Elesini, Alenka Pavko Čuden
Oddelek za tekstilstvo, Naravoslovnotehnična fakulteta, Univerza v Ljubljani, Snežniška 5, 1000 Ljubljana, Slovenija
 
Andrew F. Richards
Bolton Institute, Faculty of Technology – Textile, Bolton, UK

Abstract
Recent investigation of naturally coloured cottons have shown that brown cotton is very similar in morphology to white cotton while green cotton is different since it contains suberin. Suberin containing mainly bifunctional fatty acids can theoretically form a three dimensional network in the presence of glycerol, which is also found in green but not in white cotton. How this three-dimensional network influences the structure of the individual crystallites of cotton cellulose was investigated in this research. To confirm the presence of suberin in the green cotton fibre, infrared spectroscopy measurements were performed. According to the results of infrared spectroscopy, it was found, that O6 - H … Obridge bond which is normally found in cellulose I, is missing at the spectrum of green cotton. Additionally, two bands at 700 cm-1 and at 1201 cm-1 due to the OH - in plane bending appeared. To get a clear picture concerning the structural differences between the green cotton and the other types, the X-ray diffraction measurements and iodine absorption were carried out. According to the results we found out, that the presence of suberin does not influence the structure of the individual crystallites but hinders the development of the crystallites in the green cotton fibres.