Developing multi-functional sand-fixing materials is essential for synergistic desertification control and ecological restoration. Herein, we report a novel three-dimensional (3D) porous starch-based hydrogel sand-fixing agent (STA) synthesized via a facile one-step graft copolymerization of cationic starch and acrylic acid. By optimizing the synthesis parameters, the STA colloidal solution achieves both deep permeability (viscosity 46.3 mPa s) and high consolidation strength (unconfined compressive strength 2.31 MPa). Wind tunnel tests demonstrate exceptional wind erosion resistance of the STA-sand consolidated body, with sand fixation rates exceeding 99% for the 5.0 wt% treatment under both 30 m s −1 clean wind and 25 m s −1 sand-carrying wind conditions. Furthermore, the dried STA polymer exhibits a high water absorption capacity of 95 g g −1 and can release stored water to promote seed germination. Structural characterization confirms a chemically grafted, cross-linked 3D porous network that underpins its dual sand-fixation and water-retention functionality. This work presents a cost-effective, environmentally benign, and readily scalable starch-based material that integrates sand stabilization with water regulation, offering a practical pathway toward sustainable desertification control. • A dual-functional starch-based sand-fixing agent for concurrent sand fixation and water retention. • Systematic wind tunnel tests confirm over 99% sand fixation under extreme winds. • Sand grains are continuously encapsulated, forming a “polymer concrete” network.
Sun et al. (Fri,) studied this question.