Thermoplastic processing of thermotropic liquid-crystalline polymers under the influence of electric fields

US4668448A · kind A · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Gunter Weber · Linden, DE
• Hans-Rudolf Dicke · Bestwig, DE
• Roland Vogelsgesang · Leverkusen, DE
• Walter Simm · Leverkusen, DE
• Hermann Brinkmeyer · Krefeld, DE

Key dates

• Filing date: Jul 30, 1985
• Grant date: May 26, 1987
• Expiry date: Jul 30, 2005

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B29K2995/0041
• WIPO field: Other special machines
• WIPO sector: Mechanical engineering

Abstract

The processing by shaping, in particular includes here the moulding, spinning, extrusion, compression and injection moulding of polymers. An electric field thereby influences the flowing polymer melt before and/or during and/or after shaping. The temperature of the melt is maintained at a value between the glass temperature and the isotropic point. Thermotropic liquid-crystalline polymers are used as starting product. Among these are, in principle, all polymers which have mesogenic groups in the main and/or side chain and which can be processed from the liquid-crystalline melt phase. The orientation distribution and thus also the mechanical properties of the end product can be purposefully regulated by the electric field.