Cellulosebased nanofibers

Cellulose-based materials are useful for wound dressings and, less importantly, for sutures and related applications. Natural cellulosic materials, such as cotton, decompose before they melt, and cannot be melt-spun. Efforts have been made to regenerate cellulose from solution so as to form nanofibers. Frey [32] successfully produced electrospun cellulose fibers from polar fluid/salt solutions. It is clear from this work that cellulose nanofibers could potentially be spun from inexpensive renewable resources or reclaimed cellulosic material.

Another experimental route to the production of nanofibers based on cellulose consists of derivatizing cellulose and subsequently removing the sub-stituents at the cellulosic hydroxyl groups. For instance, cellulose acetate was electrospun from acetone, acetic acid, and dimethyl acetamide. These solvents and the resulting fibers were studied in connection with the type of collector used [33]. Depending on the composition of the solvent and the concentration of cellulose acetate, fibrous products or beads were obtained. Deacetylation with alcoholic sodium hydroxide solution was performed to various degrees of acetylation from 0.15 to 2.33 without major changes in surface characteristics.

Ding et al. [34] produced blended nanofibrous mats of cellulose acetate and poly(vinyl alcohol) PVA, extruded from separate syringes. Higher mechanical strength was achieved as the content of PVA was increased.

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