The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 16, 1990
Filed:
Oct. 06, 1989
Elvina Z Bokareva, Moscow, SU;
Jelena V Schinkorenko, Moscow, SU;
Viktor V Terenko, Moscow, SU;
Larisa A Nosova, Moscow, SU;
Garri I Faidel, Moscow, SU;
Sijar N Nurmuchomedov, Moscow, SU;
Anatolij V Beljakov, Kalinin, SU;
Ivan M Vlasov, Kalinin, SU;
Anton Fuerst, Stuttgart, DE;
Heinz Herrmann, Stuttgart, DE;
Eckart Pantzer, Freiberg/Neckar, DE;
Bernhard Stoehrer, Pleidelsheim, DE;
Eberhard Uhland, Bietigheim-Bissingen, DE;
Hans Werner, Stuttgart, DE;
Abstract
A process for separating low molecular weight compounds from a crude polycaproamide melt comprises heat treating the melt in vacuo with superheated steam, in an extruder having a plurality of degassing zones, under precise conditions of temperature, pressure and configuration, such that the occurrence of side reactions and dehydration of the melt are substantially eliminated, the molecular weight of the polymer during the heat treatment in vacuo, during transport and subsequent processing remains substantially unchanged, a residual content of low molecular weight compounds of .ltoreq.1.8% is achieved, and the operating flexibility of the process is increased.