FIBER DIFFRACTION STUDIES OF CELLULOSE SOLUBILIZATION

这个子项目是众多研究子项目之一

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Cellulose is the most abundant biopolymer on earth and is a renewable resource. This makes it an attractive research target for renewable energy studies, especially for bioethanol production. Amorphous cellulose is a much more tractable feedstock for biofuel production. We have identified a method that solubilizes cellulose with ionic liquid to produce amorphous material. On replacement of ionic liquid with water or ethanol the treated cellulose fibrils manifest varying degrees of crystallinity. We are following the crystallinity of treated material with fiber diffraction to determine the parameters of cellulose lattice disruption and amorphous cellulose production. Synchrotron X-ray fluxes are needed to produce a signal from the amorphous samples to determine the level of lattice preservation and the effects on single cellulose crystallite dissolution vs. gross fibrillar degradation. Specifically, we are asking the question of how the single cellulose crystallite is affected by solubilization, as compared with the changes seen in the overall fibril. Exposures are made of the starting fibril, the fibril after various time steps of ionic liquid treatment, and the material after the ionic liquid has been displaced with water or ethanol. The fiber is kept in a nitrogen gas stream to prevent atmospheric water from displacing the ionic liquid during diffraction experiments. As the ionic liquid is non-toxic, these experiments represent no health hazard.