| 摘要 |
Chopped fiber strands are produced by (1) wetting a continuous unsized fiber tow with a volatile agent, (2) chopping the fiber tow while still wetted with the agent in its liquid state into predetermined lengths, and (3) exposing the chopped fibers to conditions of temperature and pressure that remove the agent by volatilizing but do not cause any structural changes in the fiber. Bundles of the unsized fibers have a high bulk density and are easily dispersible in air or other media to individual filaments or groups of small numbers of individual filaments. The process is especially useful for producing high bulk density packages of polyacrylonitrile-based carbon fibers. Volatile wetting agents used are: water, alcohols, ketones, chlorinated hydrocarbons, and mixtures thereof. |
