Li-rong Nie,Shun Yao,Bing Dong,Xin-lu Li,Hang Song
In this paper, five novel cholinium-based organic magnetic ionic liquids (MILs) were synthesized. The carbon chain links to the nitrogen atom from cationic nucleus. The MILs were comprehensively identified by FT-IR, HPLC, UV–Vis, 1 H NMR and ESI-MS. The MILs have interesting performance to form aqueous two-phase system and can respond to the external magnetic field after the formation of aqueous two-phase system, which can assists magnetically phase separation. The magnetic susceptibility of the MILs was measured at 298 K. Other physical properties such as conductivities, acidity and density were measured in range of 278.15 K to 323.15 K for further application investigation. Satisfactory results were obtained after the data of physical properties were correlated. Based on the measurements and correlations above, some discussions were carried out, including the ion association and ion diffusion , the influences of MILs carbon chain and temperature on the molar conductivity , the influences of the cation size on the molar volume , acidity variation of the MILs.
In clinics it is extremely important for implanted devices to achieve the property of enhanced lubrication and bacterial resistance; however, such a strategy has rarely been reported in previous literature. In the present study, a surface functionalization method, motivated by articular cartilage-inspired superlubrication and mussel-inspired adhesion, was proposed to modify titanium alloy (Ti6Al4V) using the copolymer (DMA–MPC) synthesized via free radical copolymerization. The copolymer-coated Ti6Al4V (Ti6Al4V@DMA–MPC) was evaluated by X-ray photoelectron spectroscopy, water contact angle, and Raman spectra to confirm that the DMA–MPC copolymer was successfully coated onto the Ti6Al4V substrate. In addition, the tribological test, with the polystyrene microsphere and Ti6Al4V or Ti6Al4V@DMA–MPC as the tribopair, indicated that the friction coefficient was greatly reduced for Ti6Al4V@DMA–MPC. Furthermore, the bacterial resistance test showed that bacterial attachment was significantly inhibited for Ti6Al4V@DMA–MPC for the three types of bacteria tested. The enhanced lubrication and bacterial resistance of Ti6Al4V@DMA–MPC was due to the tenacious hydration shell formed surrounding the zwitterionic charges in the phosphorylcholine group of the DMA–MPC copolymer. In summary, a bioinspired surface functionalization strategy is developed in this study, which can act as a universal and promising method to achieve enhanced lubrication and bacterial resistance for biomedical implants.