Polyvinyl chloride fatigue

Many workers have been exposed to vinyl chloride because of its use in polyvinyl chloride plastic manufacture. The central nervous system, respiratory system, liver, and blood and lymph systems are all affected by exposure to vinyl chloride. Among the symptoms of poisoning are fatigue, weakness, and abdominal pain. Cyanosis may also occur. Vinyl chloride was abandoned as an anesthetic when it was found to induce cardiac arrhythmias. 

When polymers slide on machined metal surfaces, it is quite possible that steady-state wear Involves a combination of abrasive, fatigue, and adhesive wear mechanisms. To study fatigue wear, it would be desirable to minimize the contributions of the abrasive and adhesive wear modes. In this paper, the following polymers polycarbonate, polyvinyl chloride, ultra-high molecular weight polyethylene, siloxane modified epoxies, and polylmldes are tested in experiments in which the fatigue wear mode is predominant. 

This polyvinyl chloride compound family is highly elastomeric and exhibits a dry non-tacky surface even at hardnesses as low as 40 Shore A durom-eter. Their rubber-like resilience, high elongation and low permanent set and fatigue resistance offer advantages over conventional formulations (Tables 4.6, 4.12, and 4.13). 

Figure 3.20 The effect of molecular weight of polyvinyl chloride on fatigue crack propagation [4],...

Figure 3.30 The effect of adding methacrylate-butadiene styrene rubber (MBS) toughener to polyvinyl chloride on the fatigue crack propagation rate.

Figure 9.25 Fatigue cycles to failure versus stress in tension with a stress ratio of 0.1 at 25°C and 10 Hz for filled and unfilled polyvinyl chloride [11].

Natural rubber s utility as a blood pump material however was shortlived because of its short fatigue life and its tendency to promote blood clotting and hemolysis. Polyvinyl chloride was used in total artificial hearts (4,5), but this also was soon abandoned because it was cumbersome to handle and the surface was very thrombogenic. 

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