Process for the production of high-strength filaments from dry-spun polyacrylonitrile

US4421708A · kind A · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Manfred Reichardt · Weinsberg, DE
• Christian Pieper · Neuss, DE
• Alfred Nogaj · Dormagen, DE
• Surinder S. Sandhu · Dormagen, DE
• Eckhard Gartner · Dormagen, DE

Key dates

• Filing date: Feb 4, 1982
• Grant date: Dec 20, 1983
• Expiry date: Feb 4, 2002

Classification

• Technology area (CPC D): Textiles; Paper
• CPC primary: D01F6/18
• WIPO field: Textile and paper machines
• WIPO sector: Mechanical engineering

Abstract

High-strength filaments of dry-spun polyacrylonitrile are obtained by a process in which tension-reduced spun filaments are continuously stretched hydrothermally in one or more stages: where it involves several stages, stretching is carried out at a temperature of the stretching medium gradually increasing from stage to stage up to .theta.=.theta..sub.n and, in the final (n-th) stage, to a degree of at least 50% of the maximum degree of stretching; where it is carried out in a single stage, stretching is carried out at the optimal stretching temperature .theta..sub.n, after which the material is further treated in the conventional way, optionally with fixing of the stretched material to a pre-determined extent.