Abstract
Fibrid is a material with complex, fibrous, film-like, and intermediate forms. The diameters of the particles vary from $20-50{\mu}m$ and $100-10,000{\mu}m$. The optimal form and size of the particles depend on the area of application. The form of fibrid is the result of two processes, a wave process and diffusion. The life span and break-up pattern of the polymer depend on the interphase surface tension, viscosity of the polymer, and speed ratio of the polymer to the medium. In this study, fibrids were produced using a fibridator with high-speed shearing force. Several kinds of fibrids were obtained by changing the processing conditions, including solvent content (20, 30, and 40 wt%) in the coagulating solution, viscosity of the m-aramid dope solution (8, 10, and 12 wt%), and rotor speed of the fibridator (2000, 4000, and 6000 rpm). With low solvent content, m-aramid dope was rapidly transformed into the floc form because the coagulation rate was fast. However, as the solvent in the coagulation bath increased, the coagulation rate slowed, and the fibrids stuck together. Lower m-aramid dope viscosity and faster rotor speed were effective in obtaining proper fibrid morphology because of weakened interaction between the polymer chains.
