Piperidine

Piperidine, DBU, trifluoroacetic acid and acetonitrile (ACN) were purchased from Energy Chemical Technology (Shanghai) Co., Ltd. 2,4,6-Trimethyl-1,3,5-triazine (TMT), 2,4,6-trimethylpyridine-3,5-dicarbonitrile (DCTP), 2,4,6-tris(4-formylphenyl)-1,3,5-triazine (TFPT), 1,3,5-tris(4-formylphenyl)benzene (TFPB), 4-[4-[3,5-bis[4-(4-formylphenyl)phenyl]phenyl]phenyl]benzoic acid (DAFB), 4,4,4-(benzene-1,3,5-triyltris(ethyne-2,1-diyl))tribenzaldehyde (BTTA), 4,4’-biphenyldicarboxaldehyde (BDA), 4,4”-p-terphenyldicarboxaldehyde (TDA), 4-[2-(4-formylphenyl)ethynyl]benzaldehyde (EDA), tris(4-formylphenyl)amine (TPA), and p-phenylenediamine (Pa) were purchased from Jilin Chinese Academy of Sciences-Yanshen Technology Co., Ltd. Tetrahydrofuran (THF), 1,4-dioxane, mesitylene, benzaldehyde, NaOH, KOH, EtONa, N,N-dimethylformamide (DMF), 2,2,6,6-tetramethylPiperidine (TEMP), ethanol, methanol, CH₂Cl₂, acetone, and n-BuOH were purchased from Sinopharm Chemical Reagent Co., Ltd. Ultrapure water was prepared from the Millipore system (18.25 MΩ-cm). All the electrochemical measurement used phosphate buffered (PBS, pH = 7.5) containing mixture solutions of 0.1 M KCl, 0.1 M K₂HPO₄, and 0.1 M KH₂PO₄ as the electrolyte.

Poly(oxyethylene)nonylphenyl ether (IGEPAL CO-520), tetraethoxysilane (TEOS), and 3-mercaptopropylmethyldimethoxysilane (MPTMS) were obtained from Sigma-Aldrich Chemistry, China. 2,4-Dihyoxybenzaldehyde, ethyl acetoacetate, and piperidine were purchased from Energy Chemical Co., Ltd. Phenyl-N-tert-butyl-nitrone (PBN), triallyl isocyanurate (TAIC), 3-bromopropene, cyanoisopropyl dithiobenzoate (CPDB) and isocyanuric acid diallyl ester (IADE) were purchased from Tokyo Chemical Industry, Shanghai. Butane-1,4-diyl bis(3-mercaptobutanoate) (BD-1) and 2,2-bis(((3-mercaptobutanoyl)oxy)methyl)propane-1,3-diyl bis(3-mercaptobutanoate) (PE-1) were supplied by Chembridge International Corp., methyl methacrylate (MMA), tert-butyl acrylate (tBA) and other reagents were supplied by Sinopharm Chemical Reagent Beijing Co., Ltd. Column chromatography was performed by conventional techniques on silica gel (200−300 mesh, Qingdao Haiyang Chemical Co., Ltd.), and silica gel plates were used for TLC analysis. MMA was purified using neutral alumina column to remove the inhibitor. The solvents were dried and purified by standard laboratory methods. All other chemicals were used without any further purification unless otherwise stated.