(589a) Novel Highly Fluorinated Ionic Liquids As Nanometer-Thick Media Lubricants

Media lubricants are critical to the reliability of hard disc drives (HDDs). Ideally, the lubricants should have high thermal stability and low monolayer (ML) thickness. However, the state-of-the-art lubricant, perfluoropolyether (PFPE), only has limited thermal stability, and the ML is relatively thick. Ionic liquids (ILs) are promising candidates for the next-generation nanometer-thick media lubricants due to their excellent physiochemical properties and low ML thicknesses. However, the commercially available ILs have higher surface tension than the state-of-the-art PFPE lubricant. In the current study, a fluorinated IL (FIL) lubricant, which contains cations with highly fluorinated alkyl chains, has been successfully synthesized. The surface tension of FIL is comparable to that of PFPE, which is ideal for enhancing the tribological performance of the FIL lubricant. The thermogravimetric analysis (TGA) results showed that FIL has higher thermal stability than PFPE Ztetraol. The atomic force microscopy (AFM) revealed that, due to the intrinsically smaller molecular size of FIL, the ML thickness is only ~ 50% of that of Ztetraol, which is expected to induce a lower lubricant thickness and higher areal density. Compared to the commercially available ILs, reduced friction of the nanometer-thick FIL lubricant on carbon overcoat (COC) was also achieved due to its intrinsically lower surface tension. Our results demonstrate that the synthesized FIL lubricant has great potential for application as the next-generation lubricant in HDDs.