Spinning Carbon Fiber Precursors from 1-Butyl-3-Methylimidazolium Chloride Cellulose Solutions

Cellulose is an abundant natural renewable polymer that is used in the production of many materials. However, limited processibility and reduced solubility have restricted its use in fibers, films, and other products. Ionic liquids (IL) show promise as a new class of cellulose solvents.

The primary goal of this research was to spin highly oriented and highly crystalline cellulose fibers from an IL solution. These fibers, in addition to their environmentally advantageous processing, have potential as precursors for carbon fibers. The IL selected for this study was 1-butyl-3-methylimidazolium chloride, ([C₄mim]Cl). An elongational flow spinning technique was used to induce molecular orientation in the spinneret thus producing highly oriented, highly crystalline fibers. The effect of spinning conditions on fiber properties was determined. One prime consideration for carbon fiber precursors is the degree and size of defects. The elongational flow imposition of orientation inside the hyperbolic dies was especially effective.