Composition optimization and performance prediction for ultra-stable water-based aerosol based on thermodynamic entropy theory

Abstract

Water-based aerosol is widely used as an effective strategy in electro-optical countermeasure on the battlefield used to the preponderance of high efficiency, low cost and eco-friendly. Unfortunately, the stability of the water-based aerosol is always unsatisfactory due to the rapid evaporation and sedimentation of the aerosol droplets. Great efforts have been devoted to improve the stability of water-based aerosol by using additives with different composition and proportion. However, the lack of the criterion and principle for screening the effective additives results in excessive experimental time consumption and cost. And the stabilization time of the aerosol is still only 30 min, which could not meet the requirements of the perdurable interference. Herein, to improve the stability of water-based aerosol and optimize the complex formulation efficiently, a theoretical calculation method based on thermodynamic entropy theory is proposed. All the factors that influence the shielding effect, including polyol, stabilizer, propellant, water and cosolvent, are considered within calculation. An ultra-stable water-based aerosol with long duration over 120 min is obtained with the optimal fogging agent composition, providing enough time for fighting the electro-optic weapon. Theoretical design guideline for choosing the additives with high phase transition temperature and low phase transition enthalpy is also proposed, which greatly improves the total entropy change and reduce the absolute entropy change of the aerosol cooling process, and gives rise to an enhanced stability of the water-based aerosol. The theoretical calculation methodology contributes to an abstemious time and space for sieving the water-based aerosol with desirable performance and stability, and provides the powerful guarantee to the homeland security.