Synthesis of starch-based super absorbent polymer with high agglomeration and wettability for applying in road dust suppression.

Dust pollution is an important factor restricting social development and affecting human health, especially in some developing countries. Herein, mechanical activation-assisted solid phase reaction (MASPR) and conventional liquid phase (LP) method were employed to synthesize different superabsorbent polymers (SAPs), defined as SAP-MA and SAP-LP, respectively. The rheological properties, crystal structure, changes of functional groups, and dust suppression performance of the SAPs prepared by these two methods were compared, and the dust suppression mechanism of SAPs was discussed via the adsorption experiment between dust suppressant and dust particles. The results showed that SAPs were successfully prepared by the two methods. Compared with SAP-LP, SAP-MA with lower molecular weight, higher grafting rate, and better fluidity and water absorption showed excellent suppression performance. This enhancement could be attributed to that the SAP-MA exhibited lower crystallinity and better film-forming ability, anti-evaporation, anti-consolidation, and permeability induced by MA. Furthermore, the effective chemical adsorption between SAPs and dust particles had a stable consolidation effect. This environmentally-friendly method for the preparation of starch-based super absorbent polymer for road dust suppressant may provide new insights for the valorization of cassava starch and large-scale production of dust suppressant.