Rheological properties of sulfoacetate derivatives of cellulose

Application of cellulose sulfoacetate obtained from sugarcane bagasse as an additive in mortars

“…The cellulose obtained from purified sugarcane bagasse was sulfoacetylated according to the methodology described next, which was a modification of the Chauvelon et al 13 procedure: 1 g of cellulose and 20 mL of glacial acetic acid were shaken at ambient temperature for 10 min. This procedure was repeated.…”

“…The measurements were performed in the Chemistry Department at the University of Coimbra in Portugal with a 4.5 kHz rotation, 13 C 75.43 MHz frequency, contact time of 0.7 ms with pulses of p/2 (a 4 ls length), and a waiting time of 1 s to perform another cycle.…”

“…Water-soluble CSA, produced by the direct acetosulfonation of cellulose, was initially synthesized by Chauvelon et al 13 The incorporation of sulfate groups into the glycosidic units confers high water solubility on the derivative. This solubility is due to the contribution of sulfate groups, which reduces the initial intermolecular interaction present in the juxtaposed glucose chains (hydrogen bond); this did not allow the solubilization of cellulose because these interactions were initially very strong.…”

“…The sulfoacetate derivative was characterized by Fourier transform infrared (FTIR) spectroscopy, determination of the degree of substitution of acetyl groups (DS acet ) through a saponification reaction, determination of the degree of substitution of sulfate groups (DS sulf ) by elemental analysis, 13 C-NMR, and measures of viscosity. The application of CSA was also investigated as an additive for mortars of Portland CPV-ARI cement.…”

“…CSA presented a degree of acetylation of 2.70 and a degree of sulfonation of 0.063, and the presence of sulfate groups in the derivative displaced the position of C(6) to a lower field in the 13 C-NMR spectrum and influenced reduced viscosity as a function of concentration. The evaluation of CSA as an additive showed that for a polymer/cement ratio of 0.6%, an increase of 13.80% was achieved consistently, and an increase of 21.05% in the potential tensile of adhesion strength was also achieved.…”