Abstract:

Mechanically adaptive materials that progressively strengthen in response to repeated mechanical stimulation remain challenging to construct, particularly in aqueous environments where water-induced plasticization can compromise mechanical performance. Herein, we develop a water-activated mechanically trained self-strengthening polymer–mineral composite cement (MP@MPC). The polymer network fabricated through in situ radical ring-opening polymerization provides initial structural support, while the incorporated mineral precursors constitute a dynamic inorganic phase capable of aqueous transformation. Upon water-activated hydration, cyclic mechanical loading substantially accelerates the hydration and crystallization of the inorganic phase, promoting the formation and growth of K-struvite and consequently reinforcing the mineral network. As a result, MP@MPC exhibits pronounced mechanically trained self-strengthening, with its compressive modulus reaching 442% of the initial modulus after 50 compression–relaxation cycles. Structural and morphological analyses reveal a clear coupling between repeated mechanical loading and mineral evolution, demonstrating that mechanical loading facilitates water-mediated mineral transformation and mechanical input promotes the irreversible structural reinforcement. Beyond its adaptive mechanical behavior, MP@MPC also exhibits robust adhesion, degradability, and biological compatibility. This work establishes a polymer–mineral design strategy that couples mechanical stimulation with aqueous mineral evolution, providing a general route toward composite materials with mechanically programmable and dynamically evolving mechanical properties.