UHMWPE Definition and Comments

Definition

UHMWPE is the acronym of Ultra High Molecular Weight PolyEthylene

UHMWPE is a linear, low-pressure, Ziegler-type-catalyst, polyethylene resin.

Comments

UHMWPE has an extremely weight-average molecular weight, approximately ten times that of high molecular weight, High density polyethylene (HDPE) resins.

Because of its ultra high molecular density, UHMWPE has both the highest abrasion resistance and highest impact strength of any plastic.

In fact, a 25mm (1″) thick slap can stop a 0.38 caliber pistol slug at 150 mm (6″).

UHMWPE is the simple linear background (PE) polymers with unique properties.

UHMWPE has highest impact strength among the other engineering polymers along with excellent abrasion and wear resistance, biocompatibility, noise resistance, very low coeficient of friction, good chemical resistance and electrical insulation resistance.

Combined with abrasion resistance and toughness, the low coefficient of friction of UHMWPE yields a self-lubricating, non-stick surface.

Static and dynamic coefficients are significantly lower than steel and most plastic materials.

UHMWPE can act as a biomaterial, especially as in total joint replacement components as for example hip prosthesis or any joint replacement surgery.

Components made from UHMWPE are subject to complex loading over extended periods of time.

UHMWPE has high viscosity even above the melting temperature.

Thus, it is difficult to process pure UHMWPE by injection molding, blow molding, or conventional screw extrusion.

However, reducing the viscosity by the addition of short chain oligomers could affect the properties of the products.

The poor processability restricts the extensive existing applications of UHMWPE.

To facilitate its processing for applications, UHMWPE is combined with polyethylene (PE), polypropylene (PP), polyacrylate (PA), polycarbonate (PC), polyaniline (PANI), and other materials to improve the properties of such polymers.

High density polyethylene (HDPE) has been widely used in the industry on account of good processability, desired properties and relatively low cost.

The UHMWPE/HDPE blend has drawn much attention as a promising human joint repair material because such a blend has better creep resistance than neat UHMWPE

Furthermore, HDPE is also a biocompatible polymer and the presence of HDPE could improve the processibility of a UHMWPE blend.

Many properties of UHMWPE/HDPE blend have been studied, such as processing performance, rheological properties, thermal oxidative properties and impact behavior.

If UHMWPE is not so much known outside a circle of specialists, its applications are well-known in the industry, biomedical and protection sectors.