Submitted to: National Cotton Council Beltwide Cotton Conference
Publication Type: Proceedings
Publication Acceptance Date: February 5, 2008
Publication Date: July 5, 2008
Citation: French, A.D., Johnson, G.P. 2008. Update on Models of Cellulose cCrystals. National Cotton Council Beltwide Cotton Conference. p. 1806-1811. Interpretive Summary: Computerized molecular models of cellulose should be useful for visualizing the structures that are involved in the chemical reactions and the physical properties of cotton fibers. Potential improvements in cotton fibers could be investigated with computer software, saving time and providing guidance for further improvement. However, the present models are inadequate to the point that they do not reproduce known experimental data. Therefore, we have been continuing to improve these models. The present paper provides an update on this work, which involves larger, more realistic models and a wider range of modeling methods.
Technical Abstract: This paper describes progress in the computational modeling of cellulose crystals since our 2007 report. These crystal models are needed to better understand the interactions of cotton cellulose with water, enzymes and chemical finishing agents. Previous models resulted from molecular dynamics simulation, but many of the differences between model and experiment could be revealed with much less computer time by the energy minimization technique. The deviations of our models, and those of other workers, could be described in terms of twists of both the individual molecules and the entire crystal. Other deviations described last year have been accepted by the original authors as artifacts of the modeling techniques. The present work describes the twisting of the molecules in terms of deviations from a two-fold screw-axis, and presents results from a periodic boundary calculation with quantum mechanics.