Patent · US Expired

Extrusion grade polyethylene terephthalate

US4219527A · kind A · utility

41Cited by
6References
3Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 31, 1978
Grant dateAug 26, 1980
Priority date
Expiry dateOct 31, 1998

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB29C49/0005
  • WIPO fieldMacromolecular chemistry, polymers
  • WIPO sectorChemistry

Abstract

A process is disclosed for modifying polyethylene terephthalate so that the polyethylene terephthalate may be processed into plastic containers using conventional extrusion blow molding equipment. The polyethylene terephthalate is modified by the incorporation into a polyethylene terephthalate prepolymer of a chain branching agent and a chain terminating agent. The prepolymer is subsequently solid-state polymerized to form a polyethylene terephthalate polymer having high zero shear rate melt viscosity and shear sensitivity. This modified polyethylene terephthalate polymer may be extrusion blow molded in intermittent and continuous processes.

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