Benzylation of cellulose in the solvent dimethylsulfoxide/tetrabutylammonium fluoride trihydrate |
| |
| Authors: | L?A?Ramos E?Frollini A?Koschella Email author" target="_blank">Th?HeinzeEmail author |
| |
| Institution: | 1.Center of Excellence for Polysaccharide Research,Friedrich Schiller University of Jena,Jena,Germany;2.Instituto de Química de S?o Carlos,Universidade de S?o Paulo,S?o Carlos,Brazil |
| |
| Abstract: | The cellulose solvent dimethylsulfoxide/tetrabutylammonium fluoride trihydrate (TBAF·3 H2O) was studied as reaction medium for the synthesis of benzyl cellulose (BC) by treating the dissolved polymer with benzyl
chloride in the presence of solid NaOH or aqueous NaOH solution. BC samples with degree of substitution (DS) between 0.40
and 2.85 were accessible applying different molar ratios. The studies show that both the TBAF·3 H2O concentration and the molar ratio of the reagents to repeating unit influence the DS. The solubility of the BC synthesized
in a different way, however, of comparable DS is different. Structural analyses were carried out by means of FTIR-, 1H- and 13C NMR spectroscopy. SEC measurements revealed polymer aggregation in samples of low DS synthesized in a solvent containing
9.0% TBAF·3 H2O. At higher concentration of TBAF·3 H2O in the solvent, the BC samples obtained do not form aggregates. BC of high DS is crystalline and shows thermotropic liquid
crystalline behavior as analyzed by means of DSC. Melting point and degradation temperature are not related to the DS. |
| |
| Keywords: | Benzyl cellulose Cellulose ether Cellulose solvent Cotton linters Dimethylsulfoxide/tetrabutylammonium fluoride trihydrate Sisal cellulose Thermal properties |
| 本文献已被 SpringerLink 等数据库收录！ |
