Foam Stabilization Using a Polyacrylate–Ca ²⁺ Complex

Foams are multiphase materials with widespread applications across various industries, yet their inherent instability poses significant challenges. This study introduces a novel foam stabilization system using polyacrylate-Ca²⁺ complexes, eliminating the need for conventional surfactants. Through a combination of experiments and molecular dynamics (MD) simulations, we demonstrate that Ca²⁺ ions coordinate with carboxylate groups from multiple polyacrylate chains, forming a polymer-ion network that viscosifies the thin liquid films within the foam. This network slows fluid drainage and prevents bubble coalescence, resulting in significantly prolonged foam lifetimes. Our findings highlight the effectiveness of polyacrylate-Ca²⁺ complexes as foam stabilizers, offering a surfactant-free alternative for applications where conventional surfactants may be undesirable. This new pathway for foam design opens possibilities for creating stable foams in sensitive environmental and biomedical systems.