1 vinylimidazole

Al₂O₃ powders with an average particle size of 500 nm and 3-methacryloxypropyltrimethoxysilane (KH570, 99%) were purchased from Shanghai Aladdin Biochemical Technology Co., Ltd. (Shanghai, China) and Shanghai Macklin Biochemical Co., Ltd. (Shanghai, China) respectively, and were mainly used to prepare KH570 modified nano-Al₂O₃ (KH570-Al₂O₃). The reactants of IL and the initiator of the double bond polymerization reaction, 1-vinylimidazole (99%), 2-bromoethanol (96%) and 2,2-azobis (2-methylpropionitrile) (AIBN, 99%), were all purchased from Shanghai Macklin Biochemical Co., Ltd. (Shanghai, China). Other chemicals (analytical purity) used in this study were purchased from Hunan Huihong Reagent Co., Ltd (Changsha, China). The PUE materials were provided by Qingdao Green World New Material Technology Co., Ltd (Qingdao, China), which composed of two components: A (an isocyanate: –NCO, 6.212 wt.%) and B (a polyol: –OH, 6.358 wt.%).

PVDF (FR 904, >99.5%, Mw 400,000) was purchased from 3F New Materials Co. Ltd., Shanghai, China. Poly(ethylene glycol) methyl ether methacrylate (PEGMA, average Mn 950, contains 300 ppm BHT and 100 ppm MEHQ as inhibitor) was purchased from Aldrich (St. Louis, MO, USA). 1-Vinylimidazole (C₅H₆N₂, 99%), 1-bromobutane (C₄H₉Br, >99%), N,N-dimethylformamide (DMF, AR) and azobisisobutyronitrile (AIBN, 98%), n-hexadecane (AR, 98%) were supplied by Macklin Biochemical Technology Co., Ltd., Beijing, China. BSA (Mn 67 kDa) was obtained from Aladdin Chemical Co., Ltd., Shanghai, China. Other chemicals utilized in this study were purchased with analytical quality and purified before use. Deionized (DI) water (18.2 MΩ) purified with a Milli-Q system from Millipore (Burlington, MA, USA) was used to prepare all solutions as needed in the work.