ISSN:
1022-1352
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Physics
Notes:
Trimethylsilylcellulose (TMSC) was prepared from commercial cellulose with a mixture of hexamethyldisilazane and chlorotrimethylsilane in the solvent system N,N-dimethylacetamide/lithium chloride. The soluble, highly silylated polymer (degree of substitution, DS 2.9) had a molar mass M̄w of 500 kg/mol and a molecular non-uniformity U = (M̄w/M̄n) - 1 of 2.9. In order to investigate the principal suitability of a continuous polymer fractionation for polysaccharides like cellulose derivatives and to obtain TMSC with different molecular weights and lower non-uniformity TMSC was fractionated by means of CPF (Continuous Polymer Fractionation), well-established in the field of synthetic polymers. The samples were fractionated using a mixed solvent, composed of toluene and dimethyl sulfoxide, and characterized by capillary viscometry, gel permeation chromatography (GPC), and GPC-light scattering coupling. The molar masses of the fractions range from 110 to 600 kg/mol and their U values vary between 0.9 and 1.9. The intrinsic viscosities of TMSC in tetrahydrofuran at 25°C and M̄w are related by [η] = K · Mwa, where K = 0.0089 mL/g and α = 0.82.
Additional Material:
7 Ill.
Type of Medium:
Electronic Resource
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