Evaluation and mechanism of anionic waterborne polyurethane dispersion for chemical sand stabilisation

Chemical sand stabilisation (CSS) shows potential to collaborate with vegetation for desert restoration. Among the materials used in CSS, polyurethane (PU) is one of excellent properties but restricted by the limited forms used for CSS. This paper presents an anionic waterborne PU dispersion (PUD), a dispersion form of PU, for CSS. Its composition, particle size distribution (PSD) and zeta potential were characterised by Fourier transform infrared spectroscopy and laser particle size analyser. Results of its performance in CSS showed the stabilisation distinctly improved sand in anti-wind erosion and water-retaining properties by forming a consolidated crust on sand surface, with no harm to seed germination. The changes of stabilised sand showed strong dependence on the material concentration, which was discussed based on the visual inspection, SEM and EDS results.