Chain extended vinyl aniline modified cyclohexanone formaldehyde resin

Purpose - The purpose of this paper was as follows. The in situ chemical oxidation (ICO) of vinyl aniline modified cyclohexanone formaldehyde resin (CFVAnR) in the presence of potassium persulphate salt (K2S2O8) was accomplished in dimethyl sulphoxide (DMSO) solutions at 35°C and 70°C. The chemical composition and structure of the oxidized CFVAnR were characterised by nuclear magnetic resonance (1H-NMR) spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, DSC, TGA and SEM.Design methodology approach - The reactive vinyl and amine groups of the cyclohexanone formaldehyde resin were reacted in the presence of potassium persulphate. CFVAn resin was dissolved in DMSO inside a round bottom flask immersed in a water bath thermostated at reaction temperature of 35°C and 70°C, respectively. Solution of K2S2O8 was prepared in DMSO and this was added into the resin solution.Findings - It was shown that the vinyl groups in the resin were reacted easily with persulphate salt to obtain chain extended CFVAnR (CECFVAnR). The oxidised 4-vinyl aniline modified cyclohexanone-formaldehyde resin has solublity in organic solvents.Research limitations implications - The reaction mixture must be stirred continuously. Temperature should be controlled to prevent the thermal polymerisation of vinyl group and higher branching of amino groups. The persulphate ion (S2O82−) has a standard oxidation potential, but when activated by heat (40-60°C). Furthermore, sulphate radical can react with water or hydroxide to produce hydroxyl radical (−OH). When persulphate is used for in situ chemical oxidation (ISCO) application at relatively low temperatures (e.g.