Solid state deformation processing of crosslinked high molecular weight polymeric materials
US7993401B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 21, 2008 |
| Grant date | Aug 9, 2011 |
| Priority date | — |
| Expiry date | Feb 21, 2028 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29K2105/25
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
Solid-state deformation processing of crosslinked high molecular weight polymers such as UHMWPE, for example by extrusion below the melt transition, produces materials with a combination of high tensile strength and high oxidative stability. The materials are especially suitable for use as bearing components in artificial hip and other implants. Treated bulk materials are anisotropic, with enhanced strength oriented along the axial direction. The material is oxidatively stable even after four weeks of accelerated aging in a pressure vessel containing five atmospheres of oxygen (ASTM F2003). Because of its oxidative stability, the deformation processed material is a suitable candidate for air-permeable packaging and gas sterilization, which has thus far been reserved for remelted crosslinked UHMWPE.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.