Polyphenylmethyldimethylsiloxane is widly used in self-lubricating liquid silicone rubber, it can improves the lubricating properties of the silicone rubber, enhances its mold release properties, can also helps reduce surface defects such as sticking, tearing, or roughness, resulting in products with a smoother and more aesthetically pleasing finish. 

It exhibits good thermal stability, maintaining its lubricating and release properties over a wide range of temperatures and this is particularly important in applications where silicone rubber parts are exposed to fluctuating or extreme temperature conditions.

Overall, it plays a key role in enhancing the performance and quality of self-lubricating liquid silicone rubber by providing superior lubrication, mold release, surface quality, temperature stability, chemical inertness, and durability.