High density polythene

Fig. 1.6. The titanium alloy implant for a replacement hip joint. The long shank is glued into the top of the femur. The spherical head engages in o high-density polythene socket which is glued into the pelvic socket.

These polymers consist of long and straight chains. The examples are high density polythene, polyvinyl chloride, etc. These are represented as ... 

Wadless systems are made from a range of thermoplastics, with polypropylene and high density polythene being widely used. 

Briscoe, B. J. Pogosian, A. K. Tabor, D., "The Friction and Wear of High Density Polythene The Action of Lead Oxide and Copper Oxide Fillers," Wear, Vol. 27, 1974, pp. 19-34. 

The behavior of high density polythene is similar to that of P.T.F.E. while low density polythene behaves as a "normal" polymer. Low density polythene has a high coefficient of static friction... 

THE FRICTIONAL BEHAVIOR OF P.T.F.E. AND HIGH DENSITY POLYTHENE IN THE HIGH FRICTION REGIME... 

THE EFFECT OF LEAD ADDITIVES ON THE HIGH-SPEED FRICTION AND WEAR OF HIGH DENSITY POLYTHENE... 

Figure k shows the total wear of two specimens, unfilled and filled high density polythene, as a function of running time for two initial counterface temperatures, Tq The sliding velocity was 2.1 ms and the normal load 5.0 Kg for 5 mm diameter pins. The substrate observed temperature during the experiment is indicated at each data point (rubbing on mild steel (C.L.A.- 0.5 pm)). Four important differences between the samples are seen. 

D. Tabor We have not attempted to analyse the chain length distribution of the "extracted" polymer molecules. Such measurements would be very difficult as the amount of material available for analysis is quite small. In our experiments, we estimate that no more than 20 yg of PTFE or high density polythene could be extracted in a simple experiment. It may be possible to carry out a molecular weight analysis for examples using gel permeation chromatography. 

High density polythene, high density poly (methylene), low pressure polyethylene, linear high density polyethylene. 

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