Dissolution regeneration and stable dispersion system of monomolecular cellulose

Abstract

The invention relates to a dissolution regeneration and stable dispersion system of monomolecular cellulose. In order to separate and obtain monomolecular chain cellulose and large-scale application of the monomolecular cellulose, adenine cations of prepared high-charge nitrogen-rich adenine trifluoromethanesulfonic acid ionic liquid [Aden] (CF3SO3) 3 have three positive charges, one adenine cation [Aden] < 3 + > can be simultaneously complexed with three O atoms on three hydroxyl groups of cellulose molecules, and a-NH2 group and a-NH-group of the adenine cation [Aden] < 3 + > and an anion CF3SO3- simultaneously form a new hydrogen bond network with H atoms on the hydroxyl groups of the cellulose molecules; the high-charge nitrogen-rich adenine ionic liquid [Aden] (CF3SO3) 3 can dissolve cellulose within a short time in a low temperature range including room temperature. According to a prepared polyethylene glycol lauric acid histidine ester dispersion stabilizer, the cellulose molecules are uniformly dispersed without hydrogen bond aggregation when being separated out from the ionic liquid, and after the cellulose is centrifugally separated, single cellulose molecules still exist stably under the dispersion effect of the polyethylene glycol lauric acid histidine ester dispersion stabilizer.

Description

technical field [0001] The invention relates to a high-charge-density ionic liquid for dissolving and regenerating unimolecular cellulose and its preparation, as well as a dispersion stabilizer for unimolecular cellulose separation and its preparation, in particular to a dissolving, regenerating and regenerating unimolecular cellulose Stable dispersion system. Background technique [0002] Cellulose is the most abundant renewable natural polymer on earth, with up to 90% cellulose in cotton. However, the strong hydrogen bonding between and within the cellulose molecules, as well as the complex aggregate structure and high crystallinity of cellulose molecules limit the wide application of cellulose. Therefore, researchers have developed solvents for dissolving cellulose, including organic solvent systems, aqueous solvent systems, and ionic liquids. Organic solvent systems include paraformaldehyde / dimethylsulfoxide (PF / DMSO) system, dinitrogen tetroxide / dimethylformamide (N ...

AI Technical Summary

Problems solved by technology

At present, most of the ionic liquid cations used in the dissolution of cellulose published in patents are imidazoles. Although there are nitrogen-rich triazole and tetrazole-type energetic ionic liquids, the cations of the ionic liquids are all monovalent charges, and the charge density is low. Dissolving High temperature and long time can damage the macromolecular chains of cellulose molecules

The ionic liquid with dual-nuclear structure announced by Chinese patent CN111057007A has two positive monovalent imidazole rings, but there are hydrocarbon chain links between the two positive monovalent imidazole rings, so that the charge density is very dispersed and remains stable when dissolving cellulose. It is equivalent to an ionic liquid with a monovalent charge of the cation, so that the temperature for dissolving cellulose is higher and the time is longer, and the patent only uses the dual-nuclear structure of the ionic liquid for the degradation of lignocellulose, not for the separation of monomolecular cellulose

[0005] The authorized Chinese patent CN103657144A discloses a separation method of monomolecular cellulose, but the yield of monomolecular cellulose obtained by the separation of the patent is extremely low, and only 50 μL of the solution system can be separated at a time, and in special occasions such as after The surface of siloxane-modified mica sheets is used for the separation of cellulose, which can only be used for research and analysis, and cannot be used for large-scale development of single-molecule cellulose products

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