Patent · US Expired

Method of processing a polycondensate in a multi-screw extruder

US6841656B2 · kind B2 · utility

0Cited by
2References
21Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 2, 2003
Grant dateJan 11, 2005
Priority date
Expiry dateMay 2, 2023

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB29K2105/26
  • WIPO fieldOther special machines
  • WIPO sectorMechanical engineering

Abstract

A method for processing a polycondensate to give a granulate formed as pellets is disclosed, whereby the polycondensate is fused in the course of the method and then later resolidified. In an exemplary method, a total time during which the temperature of the polycondensate is above the melting point thereof is less than about 60 seconds. This method can be carried out by a multi-shaft extruder, whereby the degrassing and/or drying of the polycondensate in the solid state occurs at a pressure below atmospheric pressure and/or with addition of an inert gas. The time period, during which the polycondensate remains in the extruder, after being melted therein, amounts to, for example, less than about 15 seconds.

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