Preferential wetting phenomenon in bicomponent polymer melt flow

For two polymer melts spun in a side‐by‐side configuration through a capillary, interface shape and spinneret exit angle data are presented as a function of viscosity ratio, spinneret dimensions, and relative polymer‐steel wettability. Nylon‐nylon versus nylon‐polyurethane bicomponent flow systems are compared. A surface tension phenomenon is postulated to be significant in controlling the bicomponent fiber interface shape for capillary length‐to‐diameter ratios of the order of unity.