Process for production of monofilaments from polyvinylidene fluoride

US4264555A · kind A · utility

Assignee

• Dynamit Nobel GmbH · DE

Inventors

• Egon Lang · Röthis, AT
• Wilhelm Nachtigall · Troisdorf, DE
• Joachim Stark · Berlin, DE

Key dates

• Filing date: Aug 24, 1979
• Grant date: Apr 28, 1981
• Expiry date: Aug 24, 1999

Classification

• Technology area (CPC D): Textiles; Paper
• CPC primary: D01D5/0885
• WIPO field: Textile and paper machines
• WIPO sector: Mechanical engineering

Abstract

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 .degree.K., a viscosity at 100.degree. C. of over 0.5 cp and a density at 100.degree. C. of over 1.1 g/cm.sup.3. 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.