Authors:

Jiying Zou

Date Created:

Not specified

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Professor:

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About Paper:

Aqueous film-forming foams (AFFFs), used extensively by the Department of Defense for extinguishing fuel fires, contain per- and polyfluoroalkyl substances (PFAS). Due to growing environmental and health concerns associated with PFAS, developing safer alternatives has become urgent. PFAS-containing foams cause significant toxicity and persistence issues. This research aims to create a PFAS-free firefighting foam by developing temperature- and pH-responsive additives to enhance foam viscosity and stability. The primary goal is to mitigate foam degradation and improve firefighting performance without affecting foam generation and spreading. The study involves developing a viscosifying additive using pH-responsive polymers combined with temperature-responsive acids. This additive is designed to release at specific moments, enhancing foam stability and addressing related issues. Specifically, poly(methyl methacrylate-co-methacrylic acid) (PMMA-AA) is encapsulated with sodium pyrophosphate. Various concentrations of PMMA-AA solutions were prepared and tested for viscosity changes at different pH levels. The additives' viscosities were evaluated through rheological measurements, and their effects on foam stability and resistance to degradation will be tested. Preliminary results indicate that PMMA-AA solutions exhibit increased viscosity in response to pH changes. Sodium pyrophosphate shows potential in enhancing foam stability by altering the pH of the solution, inducing conformational changes in PMMA, and thereby increasing solution viscosity. Using temperature/pH-responsive additives in firefighting foam formulations could provide a promising approach to developing effective PFAS- free alternatives, addressing the environmental and health concerns associated with traditional PFAS- containing foams. Keywords: Responsive Additives; pH Adjuster; AFFFs; PFAS; PFAS-free Fire Fighting Foam

Source:

Purdue University / 2024

Topics:

No topics listed

Co-authors:

Jiying Zou