Purging for spinning hydrated acrylic polymer melt

In the process of melt-spinning acrylonitrile polymer fiber which comprises furnishing a composition of acrylonitrile polymer and water in solid form to a compacting zone, converting said polymer and water composition to a homogeneous single-phase fusion melt while in said compacting zone, and extruding the resulting fusion melt through a spinnerette assembly, the improvement which comprises adding a purge composition prior to or subsequent to said furnishing of said polymer-water composition, said purge composition comprising from about 65 to 85 weight percent of an acrylonitrile copolymer, from about 15 to 35 weight percent of ethylene carbonate, and from 0 to about 5 weight percent of water, said purge being in solid state at a temperature below about 40.degree. C. and atmospheric pressure and having a melt viscosity which is about equal to or greater than that of the fusion melt to be purged or extruded at the melting temperature of said fusion melt, the quantity of purge composition employed being sufficient to fill the processing areas of said compacting zone and said spinnerette assembly.