Multi-component elastomeric composites based on castor oil/AgI/KI for cloud seeding: processing and modeling of reagent efficiency

Abstract

This study involves the development of sustainable technology/methodology for the production, characterization and numerical calculation of highly effective multi-component anti-hail seeding reagents (seeding composites) based on silver iodide and iodide of an alkali metal, homogenized in synthetic or bio polyurethane binder. Polyurethane-based seeding composites are produced via casting method and the results of uniaxial tensile tests, hardness and dynamic-mechanical analysis show that applied technique is more suitable compared to the conventional dry homogenization of the seeding active agents. Lower viscosity, uniform powdered seeding agents distribution and improved mechanical properties, e.g. higher tensile strength (5.05 MPa) and Shore A hardness (89 ShA) are achieved using castor oil as bio-polymer binder, compared to the synthetic polymer hydroxyl terminated poly(butadiene). In addition, significantly higher glass transition temperature obtained for seeding composite with castor oil as polymer binder indicating higher density and branched polymer network. Numerical models of the convective clouds are used to determine composition and mass of seeding agent which gives the best results concerning hail suppression or rain intensification. Results show that composite seeding reagents which contain silver iodide and potassium iodide in a molar ratio of 1:2 upon combustion generate freezing nuclei which are active above 0 °C, providing the most effective cloud seeding with 10.53% hail accumulations suppression. Graphical abstract: [Figure not available: see fulltext.]