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An unconventional system for cellulose acetate hydrolysis, consisting of homogeneous mixtures of benzene/acetic acid/water of different compositions, was investigated from the perspective of kinetics and also with respect to the degradation of the cellulosic chains during the process. It was observed that the decrease of the degree of substitution of the polymer occurs with higher reaction rate than that in the reference system, free of benzene, and depends on the composition of the reaction medium. A pseudo-first-order kinetic law satisfactorily describes the deacetylation process performed in the presence of benzene. Also, the degradation of the polymeric chain during the process is dependent on the presence of the hydrocarbon and on the composition of the reaction system used. A lower degradation rate was found to characterize the first period of the process, compared with that produced in a benzene-free system. These peculiarities were explained by the influence of benzene on the composition of solvent shell in the vicinity of macromolecules.

Electrospinning of cellulose acetate phthalate (CAP) has been performed from an acetone−water mixture 85/15 (v/v), 2-methoxyethanol, and a 2-methoxyethanol−acetone−water mixture 50/42.5/7.5 (v/v/v). It has been observed that, at low polymer concentration (12.5%, w/v), a solution in an acetone−water mixture 85/15 (v/v) gave uniform fibers with diameters lower than 500 nm, whereas in 2-methoxyethanol fine particles that look like void hemispheres were obtained. The morphology of the electrospun CAP from this solvent gradually changed by increasing the polymer concentration and beaded fibers and fibers without beads have been produced from solutions of 25% (w/v) and 35% (w/v), respectively. Smooth filaments with no beads and diameters of about 600 nm could be obtained from a solution of CAP in the ternary system 2-methoxyethanol−acetone−water 50/42.5/7.5 (v/v/v) at a polymer concentration of 25% (w/v). The electrospinnability of CAP from 2-methoxyethanol-containing solvents was better than that from the acetone−water mixture 85/15 (v/v).