Affect of dope additives on finishing behavior of carbon fiber precursors

Finishing kinetics of acrylic precursor fibers was studied by using a new CGB finish. Effects of dope additives including polyvinyl pyrrolidone, glycerol, and polyvinyl acetate on finishing behavior of acrylic precursors were contrastively discussed. Diffusion coefficients for the finish were calculated from the Crank's equation. It is shown that the precursor fibers applied with the CGB finish do not give fluffs, broken, and adhered precursors. The increase of the finish uptake values is greater around the glass transition temperature, and the changes of uptake become less prominent as the finish bath temperature above the glass transition temperature. By use of the dope additives, the finish uptake values are enhanced; the diffusion coefficient for the finish is higher; the activation energy required for the finish is lower; the extent being greatest for the fibers containing polyvinyl pyrrolidone. The properties of the finished precursor fibers containing polyvinyl pyrrolidone are the best. (C) 2003 Wiley Periodicals, Inc.