Methyl ethyl ketone

Butyl acrylate (>99%), 2-ethylhexyl acrylate (>99%), ethyl acrylate (>99%), 2-hydroxyethyl acrylate (>95%), acrylic acid (>99%), abietic acid (>80%), triethylamine (>99%), and 2-isocyanatoethyl methacrylate (>98%) were purchased from Tokyo Chemical Industry. Tris(4-hydroxyphenyl)methane triglycidyl ether (>95%) and dibutyltin dilaurate (95%) were purchased from Sigma-Aldrich Korea Ltd. (Yongin, Korea). Toluene (99.5%), ethyl acetate (99.5%), and methyl ethyl ketone (99.5%) were purchased from Samchun Chemical (Pyeongtaek, Korea). Azobisisobutyronitrile (AIBN, 98%) was purchased from Junsei Chemical (Tokyo, Japan). All chemicals were used as received without further purification. The epoxy crosslinker was used after dilution to a solid content of 5 wt% with Toluene. A 17-μm-thick graphite sheet was purchased from Tanyuan technology (Changzhou, China). A silicone-coated polyethylene terephthalate (PET) film and a polyethylene terephthalate (PET) film were purchased from SKC (Seoul, Korea). A stainless steel (SS) plate was purchased from MMSTECH (Bucheon, Korea). The micro structure of the g-TC film was analyzed using a scanning electron microscope (SEM, JSM 6380, JEOL, Tokyo, Japan) and a digital microscope (MXB-5000REZ, HIROX, Tokyo, Japan).

Hot-dipped Zn alloy-plated steel was obtained from POSCO (Korea). The zinc alloy layer comprises 97% Zn, 1.5% Mg, and 1.5% Al. Cr(NO₃)₃ and ethanol (absolute) were purchased from UNICOH (Korea) and Sigma-Aldrich (St. Louis, MO), respectively. Due to the carcinogenic nature of hexavalent chromium, we utilized trivalent chromium for the conversion coating process. Thiolated polyethylene oxide (PEO-SH, Mw: 356 g/mol) was procured from Polypure (Oslo, Norway). Nitric acid (60%) and methyl ethyl ketone were obtained from SAMCHUN (Korea) and DAE JUNG (Korea), respectively. Deionized (DI) water (18.3 MΩ·cm) was obtained using a reverse osmosis water system (Human Corporation, Korea).