Process for melt spinning acrylonitrile polymer fiber using hot water as stretching aid

A process for producing an acrylonitrile polymer fiber which comprises preparing a single phase melt of acrylonitrile polymer and water, extruding said melt through a spinneret directly into a steam-pressurized solidification zone maintained under conditions of temperature, pressure and saturation that enable the nascent extrudate to solidify, and to retain sufficient water to remain in a stretchable plastic state, wetting the extrudate with hot water and stretching the wetted extrudate in at least two stretch stages so as to provide molecular orientation thereof while it remains within said solidification zone.