TPV vs. PVC

Whether designing a static or dynamic seal, it is important not to overlook the long-term performance of the elastomer. Here are some facts you should know when choosing a material for your seal.

PVC is a common choice for seals, and has been around a long time. In our experience, however, flexible PVC does not hold up well over the years, especially if subject to warm air. In a heat aging test conducted by an independent lab, Reed held dozens of TPV and PVC specimens in a heat aging chamber for 12 weeks at 100°C. The results were dramatic: the TPV specimens changed very little, but the PVC specimens shrank by nearly 10%, and became much harder and less elastic. Of course, your seal may never see these temperatures, but the results do suggest how these two materials will perform at lower temperatures over an extended period of time. Also, different grades of TPV and of PVC could yield somewhat different results, but these findings are consistent with most of the literature available. Our results are tabulated below.

TPV vs. PVC