The process oil that is used in PE battery separators has a triple role:

• It permits the gel-processing of UHMWPE, which as a result of high chain entanglement, does not melt-process.
• The extraction of the process oil from the silica-filled, UHMWPE-bound battery separator creates a porous film with pores averaging 26 and 27 nanometers in diameter.
• The oil that remains in the separator serves as initial protection for the UHMWPE against high-temperature electrochemical oxidation.

ENTEK International uses process oils with unique design characteristics to enhance the lead-acid battery's life and performance. Years and years of development work have created the most oxidation-resistant separators in the world as proven in Hi-Temperature Loss of Elongation BCI (BATTERY Council International) Perox 80° testing (extended to 72-hours), Hi-Temperature Loss of Puncture Strength, Japanese Overcharge testing, and Japanese "upside-down" Overcharge Oxidation testing, Honda Complex Life Cycle testing, etc.