Cellulose in ionic liquids: getting solvent in or out.

Cellulose is a biodegradable polymer of many uses. It is soluble in some ionic liquids(IL), being environmental solvents. This implies complex interactions between chain and the two IL constituents. We observed that SAXS at large concentration is different from what expected for a usual polymer solution. Moreover, in presence of a few % of water (IL are hygroscopic), an even stronger scattering is measured. This suggests strong concentration fluctuations, getting solvent out of possible clusters. Our first goal here is to study concentration fluctuations, over the full q range. We need a higher flux than lab SAXS due low contrast and low concentrations of chains and water; D2AM is sufficient for medium q range. We need ID02 for its irreplaceable low q range. Our second goal is in-situ study solvent penetration in nanocellulose crystals of a textile fiber, through scanning exploration of a gradient of concentration during swelling. We need a narrow beam only available on synchrotron.