A new approach for blending waste plastics processing: Superabsorbent resin synthesis

The current study reports a multi-functional superabsorbent resin (SAR) developed from blending waste plastics. The new process successfully overcame the incompatibility of blending waste plastics through polymerization process and the products could be used as water-retaining agent and desiccant. Structure studies indicated that the monomer was successfully grafted onto the blending waste plastics, causing improved thermal stability and a porous and coarse surface. The maximum water absorbing capacities reached 343 and 125 g/g in distilled water and tap water, respectively, and the optimum operation temperature, reaction time, mass ratio of waste plastics to monomer, the amounts of cross-linker and initiator were respectively 95 degrees C, 3 h, 1:8, 0.25 wt% and 0.60 wt%, The swelling kinetic mechanism of the prepared SAR was well described by pseudo-second order and non-Fickian diffusion type followed an anomalous mechanism. Moreover, the product could be applied in a vast pH range of 3-10, and also could be cyclic utilization. In addition, the SAR showed superior moisture absorbing capacity which was 3-5 times higher than that of commercial desiccants under the same condition. Accordingly, this study provides a practical, environmentally friendly and high value-added approach for blending waste plastics recycling. (C) 2018 Elsevier Ltd. All rights reserved.