Influence of substitution of direct dye having biphenylenebis(azo) skeletal structure on nascent cellulose produced by Acetobacter xylinum [II]

The influence of Direct Blue 14 and 53 dyes, both having biphenylenebis(azo ) skeletal structure but different sulfonate groups substitution on the str ucture of the nascent microbial cellulose was examined. The product obtaine d from the Acetobacter culture in the presence of each dye is a characteris tic dye-cellulose complex, and the dye molecule is included between the cel lulose sheets in the complex corresponding to the (1(1) over bar 0) plane o f microbial cellulose. Due to the inclusion of dyes between the cellulose s heets through hydrogen bonding or van der Waals forces, the hydrogen bondin g between cellulose chains of microbial cellulose is hindered. The differen t position of sulfonate groups has no major influence on the two products e xcept on the uniplanar orientation of the product. Celluloses regenerated f rom both products are cellulose II, but their fine structures are different from each other. (C) 1999 John Wiley & Sons, Inc.