Pure, well soluble p-toluenesulfonyl (tosyl) starch samples with a DSTos range from 0.4 to 2.0 were prepared by reacting starch with tosyl chloride in the presence of triethylamine dissolved in the solvent N,N-dimethyl acetamide in combination with LiCl. The thermal degradation starts at a temperature of 166 °C for a sample with DSTos of 0.61 which is sufficiently high for subsequent modifications of the remaining OH groups, for instance by acylation reactions. The total DSTos can be determined using the signal of the methyl protons of the tosyl, acetyl or propionyl moieties of peracylated samples. Moreover, the NMR characterisation reveals that a predominant functionalisation at position 2 occurs. On the other hand, 6-O-tosyl starch products can be synthesised via 2-O-acetyl starch which is accessible by a new acylation procedure. The functionalisation patterns of new synthesised polymers with an unusual distribution of functional groups and high DS values were unambiguously characterised by various NMR techniques.
KeywordsSulfonyl Chloride Starch Sample Starch Product Tosyl Chloride Starch Derivative
Unable to display preview. Download preview PDF.
- 1.Heinze, Th., Glasser, W.G., 1998, The role of novel solvents and solution complexes for the preparation of highly engineered cellulose derivatives. In Cellulose derivatives: modification, characterization, and nanostructures, (Thomas J. Heinze, Wolfgang G. Glasser, eds.) ACS Symposium Series 688. Washington, DC: American Chemical SocietyCrossRefGoogle Scholar
- 2.Wurzburg, O.W., 1986, Modified starches: properties and uses. Boca Raton, USA: CRC PressGoogle Scholar
- 11.Klemm, D., Stein, A., 1995, Silylated cellulose materials in design of supramolecular structures of ultrathin cellulose films. J.M.S.-Pure Appl. Chem. A32: 899–904.Google Scholar
- 12.Matulova, M., Toffanin, R., Navarini, L., Gilli, R., Paoletti, S., Cesaro, A., 1994, NMR analysis of succinoglycans from different microbial sources: partial assignment of their 1H and 13C NMR spectra and location of the succinate and the acetate groups. Carbohydr. Res. 65: 167–179.CrossRefGoogle Scholar
- 14.Dicke, R., 1999, Ph.D. Thesis, Friedrich Schiller University of Jena, Germany.Google Scholar
- 18.Dicke, R., Rahn, K., Haack, V., Heinze, T., Starch derivatives of high degree of functionalization 2. Determination of the functionalization pattern of p-toluenesulfonyl starch by peracylation and NMR spectroscopy. Carbohydr. Polym., in press.Google Scholar
- 19.Heinze, T., 1998, Ionische Funktionspolymere aus Cellulose: Neue Synthesekonzepte, Strukturaufklärung und Eigenschaften. Shaker Verlag, AachenGoogle Scholar