Patent · US Expired

Process and apparatus for removing evaporable components from polyamide melts

US4128453A · kind A · utility

1Cited by

5References

3Claims

0Family size

Assignee

Zimmer, Inc. · US

Inventors

Dieter Angerer · Großkrotzenburg, DE
Peter C. Freund · Ketsch, DE
Werner Hansel · Karben, DE
Fritz Wilhelm · Karben, DE

Key dates

Filing date	Dec 22, 1975
Grant date	Dec 5, 1978
Priority date	—
Expiry date	Dec 22, 1995

Classification

Technology area (CPC Y)Emerging Cross-Sectional Technologies
CPC primaryY10S159/10
WIPO fieldMacromolecular chemistry, polymers
WIPO sectorChemistry

Abstract

An apparatus and process for removing undesired monomers and oligomers from polyamide melt at subatmospheric pressure by passing steam through the melt to absorb the undesired components and carry them away. Various constructions are disclosed for vigorously intermixing the gas with the melt in which the gas is passed through a foraminous surface over which a thin film of melt flows, and a rotating agitator, spaced less than 50 mm from the surface, mixes the gas with the melt film. In a preferred form of the invention the rotating shaft comprising the agitator carries screw threads and serves as a conveyor for discharging treated melt from the pressure vessel in which the process is carried out.

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