Patent · US Expired

Process for the continuous, counter flow/direct flow extraction of polyamides

US4978743A · kind A · utility

23Cited by

1References

9Claims

0Family size

Assignee

BAYER HEALTHCARE LLC · DE

Inventors

Harald Selbeck · Krefeld, DE
August Horsthemke · Krefeld, DE
August Bockmann · Krefeld, DE
Frank Elmo Weber · Plochingen, DE

Key dates

Filing date	Sep 19, 1988
Grant date	Dec 18, 1990
Priority date	—
Expiry date	Sep 19, 2008

Classification

Technology area (CPC C)Chemistry; Metallurgy
CPC primaryC08G69/28
WIPO fieldMacromolecular chemistry, polymers
WIPO sectorChemistry

Abstract

This invention relates to a process for the continuous extraction of polyamides, in which the residue of low molecular weight components left in the polyamide is very small. It also relates to a two-part extraction tube suitable for this purpose, in which the upper part is connected to the lower part by a transition tube of smaller diameter and a counterflow extraction is carried out in the upper part and a direct flow extraction in the lower part under particular conditions.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.