Media lubricants are critical to the reliability of hard disc drives (HDDs). Ideally, the lubricant should have high thermal stability and low monolayer (ML) thickness. Unfortunately, the state-of-the-art lubricant perfluoropolyether (PFPE) only has limited thermal stability, and its ML is relatively thick due to the polymeric chain structure. In this study, we showed that an ionic liquid (IL) with imidazolium cations and fluorinated anions, [Bmim]­[FAP], has higher thermal stability than PFPE Z-tetraol based on thermogravimetric analysis (TGA). Moreover, both AFM and friction test results demonstrated that the ML thickness of [Bmim]­[FAP] is only ∼50% of that of PFPE Z-tetraol, which can be attributed to the smaller molecular size of [Bmim]­[FAP]. These findings suggest that ILs are promising candidates for the next-generation media lubricants.

Ionic liquids (ILs) are promising candidates for the nextgeneration nanometer-thick lubricants in hard disc drives (HDDs) because of their excellent physiochemical properties and low monolayer (ML) thicknesses. However, the commercially available ILs have higher surface tension and higher friction than the state-of-the-art perfluoropolyether (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 results showed that FIL has higher thermal stability than PFPE Ztetraol. Atomic force microscopy revealed that because of 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 nanometerthick FIL lubricant on carbon overcoat was also achieved because of its intrinsically lower surface tension. Our results demonstrate that FIL has great potential for application as the next-generation media lubricant in HDDs.

Ionic liquids (ILs) have attracted intensive research interest due to their outstanding physiochemical properties. However, comprehensive design is necessary for targeted applications and has rarely been conducted. As a result, the industry‐scale application of ILs is still very limited. In this academia–industry collaborative research among the University of Pittsburgh, Virginia Tech. University, and Seagate Technology LLC, we report the design, synthesis, molecular dynamics (MD) simulation, and characterization of a nanometer‐thick IL, which contains abundant fluorinated segments and a hydroxyl endgroup, as the next‐generation nano‐lubricant for hard disk drives (HDDs). The lab‐ and industry‐level testing results indicate that the IL lubricant performs significantly better than the state‐of‐the‐art lubricant, that is, perfluoropolyether (PFPE) that has been utilized for three decades in the HDD industry in two key functions: thermal stability and fly clearance. Meanwhile, the IL lubricant also shows excellent lubricity and durability. The outstanding performance of the IL has been attributed to its unique molecular structure on the solid substrate, which is supported by MD simulation results. Our work establishes the IL as a promising candidate among the next‐generation media lubricants in HDD industry. Meanwhile, the finding obtained here has important implications in many other applications involving nano‐lubricants.

Maleic anhydride is an important raw material in many chemical reactions, and very often, condensation is required to reflux maleic anhydride back to the reactor. It has been shown that severe fouling occurs to the maleic anhydride condenser, which is a major challenge to the operation in chemical plants. Clearly, an efficient mitigation plan is highly dependent on the understanding of the underlying mechanisms. However, the mechanisms of the fouling in the maleic anhydride condenser remain unclear to date. Here we report our experimental efforts in (1) uncovering the governing mechanisms of the fouling in maleic anhydride condensers and (2) developing the strategy to combat the condenser fouling. Our in-situ interface characterization and 1H NMR results suggest that the condensed maleic anhydride, which is a liquid, is pinned on the condenser surface and thus reacts with the trace amounts of water to produce maleic acid, which is a solid. The maleic acid solid particles accumulate on the condenser surface and over a short period of time, i.e., days to weeks, will plug the condenser tubes. The key enabler of this process is that the maleic anhydride droplets are pinned on the tube surface and do not roll off the surface, which results from the high roughness of the condenser surface. We found that, after the surface roughness is reduced by machining, the maleic anhydride droplets roll off the tube surface much more easily, indicating this is a promising approach to reduce the condenser fouling.

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