One of the prominent features of STPA sealant is the excellent oil resistance at ambient or even at high temperatures. The cured material of STPA polymer is very similar to acrylic rubber, which is well known for having excellent oil and heat resistance and is used in automotive applications. Results of oil and chemical resistance test are shown in Table 4.
FIG. 12—Self-cleaning mechanism of photocatalytic glass (SCG).
The STPA sealant exhibited very good oil resistance against a couple of standard oils even at 150 ° C.
Silicone is also used for applications requiring heat and oil resistance because silicone has excellent heat resistance and low oil-swelling property; however, the latter is still higher for silicone than for STPA based materials. Actually silicone is very durable in oil at high temperature, but some oil is seeping through silicone without any seal failure occurring. On the other hand, STPA based materials can almost completely eliminate the oil penetration problem