Hydrophobic aromatic acrylamide copolymerization-induced in situ bicontinuous networks for ultra-robust and impact-resistant eutectogels.
Lv Wenjia W, Han Jiaxi J, Du Jiaqiang J, Zhou Shan S et al.
Developing polymer gels that integrate high strength, stiffness, and toughness for impact protection remains challenging. Here, we present a synergistic molecular-structural design strategy to fabricate ultra-robust eutectogels by copolymerizing N-benzylacrylamide (BA) and acrylic acid (AA) in a deep eutectic solvent (DES) composed of choline chloride (ChCl) and glycerol (Gly). The contrasting solvent affinities of the two comonomers drive the spontaneous formation of a bicontinuous network, where the PBA-rich phase dissipates energy through hydrogen-bonded hydrophobic domains and the PAA-rich phase enables stress transfer and stretchability. The resulting gel achieves a fracture strength of 17.0 MPa, a modulus of 313.7 MPa, and a fracture toughness of 112.8 kJ m-2. Furthermore, the dynamic network imparts reliable self-recovery, self-healing, solvent-mediated reprocessability, and thermally promoted adhesion. The impact-protection performance is validated by falling-ball tests (yielding a 60% reduction in peak impact force) and the effective protection of fragile items. This molecular and structural engineering strategy is demonstrated to be generalizable to other miscible vinyl monomers and solvent systems, offering a promising solution to design robust polymer gels for next-generation soft protective materials.