Process for production of monofilaments from polyvinylidene fluoride

摘要

A process for the production of monofilaments of polyvinylidene fluoride is disclosed wherein polyvinylidene fluoride is plasticized in an extruder and fed to an extrusion die and passed through an extrusion nozzle orifice to enter a liquid cooling medium having a thermal conductivity of under 0.4 W/m DEG K., a viscosity at 100 DEG C. of over 0.5 cp and a density at 100 DEG C. of over 1.1 g/cm3. Extusion is performed by passing the plasticized polyvinylidene fluoride over separate extrusion zones such as by passing the polyvinylidene fluoride over a first extrusion zone maintained at a first extrusion temperature and thereafter passing the polyvinylidene fluoride through a second extrusion zone maintained at a temperature of 10 to 30 percent higher than the preceeding extrusion zone. An apparatus for carrying out the process is also described.