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Materials of Construction - UHMWPE
March 13, 2003
| Common Name |
UHMWPE |
| Chemical Name |
Ultra High Molecular Weight
Polyethylene |
| Trade Names |
RCH 1000 (Hoechst’s
early trade name for UHMWPE)
Hostalen GUR 1020 (Type 1) (manufactured by Hoechst/Ticona, Inc.)
Hostalen GUR 1050 (Type 2) (manufactured by Hoechst/Ticona, Inc.)
1900H (Type 3) (previously manufactured by Basell Polyolefins, now discontinued) |
| General |
Ultra-high molecular weight
polyethylene (UHMWPE) is a unique polymer with outstanding physical and mechanical
properties. For the past 40 years, UHMWPE has been used in orthopedics as a bearing
material in artificial joints. Each year, about 1.4 million joint replacement procedures
are performed around the world. Despite the success of these restorative procedures,
UHMWPE implants have only a finite lifetime. Wear and damage of the UHMWPE components is
one of the factors limiting implant longevity. UHMWPE comes from a family of polymers with a deceptively
simple chemical composition, consisting of only hydrogen and carbon. However, the
simplicity inherent its chemical composition belies a more complex hierarchy of
organizational structures at the molecular and supermolecular length scales. At a
molecular level, the carbon backbone of polyethylene can twist, rotate, and fold into
ordered crystalline regions. At a supermolecular level, the UHMWPE consists of powder
(also known as resin or flake) that must be consolidated at elevated temperatures and
pressures to form a bulk material. Further layers of complexity are introduced by chemical
changes that arise in UHMWPE due to radiation sterilization and processing. |
| Specifications |
ASTM
D4020 Standard Specification for
Ultra-High-Molecular-Weight Polyethylene Molding and Extrusion Materials
ISO
11542-1 gives a range of viscosity numbers that defines the viscosity of UHMW-PE grades.
The viscosity numbers are determined in accordance with ISO 1628-3. |
| Application |
General
- Bearing material in artificial joints
Sulphuric Acid Plants
- Weak acid pumps (i.e. Wernert)
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