Cellulose Tritylation Via Tridimensional Regioselective Substitution And Its Construction Of New Cellulose Derivatives

Cellulose is one of rich macromolecular polymer resources on the earth, but there is a bigstumbling block to make use of cellulose and its derivatives because of strong crystalstructure and abundant hydrogen-bonds of cellulose with intra-chain positions and inter-chainpositions. Based on the three hydroxyls with differences in the reactivity, regioselectivesubstitution is a hot research and utilization direction for utilizing cellulose efficiently atpresent.This paper summarizes the recent advances in cellulose derivatives via regioselectivelysubstituting pathway in detail. Homogeneous treatment with cellulose by ionic liquid andheterogeneous treatment with cellulose by NaOH and EDA were realized in the laboratory.The differences on molecular weights、crystalline structures、chemical structures and surfacetopographies were tested by FT-IR、XRD、TGA、SEM respectively. The pathway andtechnology condition of cellulose tritylation were studied deeply and groped repeatedly.Besides the paper also emphatically studied the pathway and technology condition ofcarboxylation and fluorination, the experiment phenomena and results were explained anddemonstrate by FT-IR、XPS、NMR (1H-NMR、13C-NMR、2D-1H,1H-NOESY) detectionmeans. Based on the trityl cellulose, a new type of macromolecular cellulose derivative wassuccessfully synthesized by grafting two different chemical functional groups on the cellulosestructural units.The experimental results showed that AHIMCl serving as homogeneous solvent hasmore effective on cellulose structures than heterogeneous treatment. The tritylation ofcellulose could succeed in BMIMCl and AHIMCl, and AHIMCl showed more effective thanBMIMCl. Not only did trityl groups exist in the location C6of ellulose structural units, butalso it was on location C2. The vast majority of trityl groups can be removed in thedetritylation of cellulose except very tiny amount of it. BMIMCl and toluene can serve aseffective solvents for trityl cellulose to be fluorination, but DMSO can not. Using twodifferent ways can remove the trityl groups of2,3-O-CH2COONa-6-O-trityl cellulosesuccessfully, however it didn’t work on2,3-O-CO(CF2)6CF3-6-O-trityl cellulose. Anhydridewas synthesized by-COOH or-COONa and ClCO(CF2)6CF3reaction in the process of preparing2,3-O-CH2COOH-6-O-CO(CF2)6CF3cellulose, furthermore anhydride react withCH3OH to form2,3-O-CH2COOCH3-6-O-CO(CF2)6CF3cellulose under washing of CH3OH.The final product, i.e.2,3-O-CH2COOH-6-O-CO(CF2)6CF3cellulose was synthetized withwater.