Synthesis of new cationic surfactants based on recycled poly(ethylene terephthalate) for deinking of solvent-based ink from low-density polyethylene surface



Water-soluble oligomers based on poly-(ethylene terephthalate) waste, PET, were prepared from transesterification of PET with diethanolamine and triethanolamine in the presence of manganese acetate as a catalyst at temperature of 200°C for 8 h. New cationic surfactants were prepared by reaction of the produced recycled oligomers with bromoacetic acid followed by quaternization with pyridine. The chemical structure of the prepared surfactants was confirmed by 1H-NMR analysis. The surface tension, critical micelle concentration, and surface activities were determined at different temperatures. Surface parameters such as surface excess concentration (Γmax max), the area per molecule at interface (Amin), and the effectiveness of surface tension reduction (∏CMC) were determined from the adsorption isotherms of the prepared surfactants. The prepared surfactants were tested as ink removal for printed low-density polyethylene surface. The effect of surfactants concentrations, pH, soaking time, and shaking time were investigated for deinking process. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010