“Dual pH‐and Temperature‐Responsive P (AAc‐co‐C16A) Shape‐Memory Hydrogels for Controlled Drug Release”

This study presents an amphiphilic shape‐memory hydrogel (SMH) based on poly(acrylic acid‐co‐n‐hexadecyl acrylate) [P(AAc‐co‐C16A)] that integrates pH and temperature responsiveness within a single molecular network. The hydrophobic C16 side chains form reversible crystalline domains that act as physical cross‐links, imparting thermal shape‐memory and mechanical strength, while ionizable acrylic acid units provide pH‐dependent swelling and charge regulation. An optimal composition containing 30 mol % C16A exhibited a balanced combination of mechanical robustness (E ≈ 15 MPa), a high shape‐recovery ratio (>93 %), and a thermoresponsive transition near physiological temperature (37°C–39°C). Ibuprofen‐loaded SMHs demonstrated strongly pH‐dependent and thermally accelerated drug release, with enhanced release under mildly acidic conditions and further acceleration upon shape …