Biopolymer-Templated Calcium Silicate Hydrate Hybrids for High-Performance Inorganic–Organic Nanocomposite Films

Controlling the nucleation, dispersion, and organization of calcium silicate hydrate (C-S-H) nanoparticles is essential for engineering C-S-H-based materials with tailored structures and mechanical properties. Inspired by biopolymer-mediated mineral stabilization and hierarchical assembly in seashells, this work highlights the dual role of carboxylated cellulose nanocrystals (cCNCs) in dispersing C-S-H nanoparticles, templating their nucleation, and directing their assembly into hierarchical structures. The rigid, rod-like morphology of cCNCs serves as a scaffold, guiding C-S-H growth and facilitating the development of organic–inorganic hybrids (cC-C-S-H). These hybrids exhibit both spatial uniformity and directional order, enabling their effective assembly with poly(vinyl alcohol) (PVA) via a casting–evaporation process into hierarchical architecture. As a result, the resulting nanocomposite demonstrates outstanding mechanical performance, achieving a tensile strength of 44.6 MPa, a tensile strain of 444.9%, and a toughness of 12,558 kJ m–3. In addition, the dynamic interfacial interactions between the C-S-H-based hybrids and PVA impart good self-healing capabilities to the nanocomposites. This work provides a bioinspired strategy for engineering C-S-H-based inorganic–organic nanocomposites and establishes design principles for future development of C-S-H hybrid building blocks for cementitious materials and other multifunctional applications.