Solid state deformation processing of crosslinked high molecular weight polymeric materials

US8262976B2 · kind B2 · utility

Assignee

• Biomet Manufacturing, LLC · US

Inventors

• David W. Schroeder · Winona Lake, US
• Jordan H. Freedman · Fort Wayne, US
• James E. Gunter · Claypool, US
• Brian D. Salyer · Warsaw, US
• H. Gene Hawkins · Warsaw, US

Key dates

• Filing date: May 22, 2009
• Grant date: Sep 11, 2012
• Expiry date: Oct 3, 2029

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08J2323/06
• WIPO field: Medical technology
• WIPO sector: Instruments

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 desirable combination of physical and chemical properties. Crosslinked bulk materials are heated to a compression deformable temperature, and pressure is applied to change a transverse dimension of the material. After cooling and stress relieving, a treated bulk material is obtained that has enhanced tensile strength in the axial direction orthogonal to the dimension change. In preferred embodiments, medical implant bearing materials are machined from the treated bulk material with the in vivo load bearing axis substantially parallel or coincident with the axial direction of the treated bulk material.