Covalent Integration of Poly(α-lipoic acid) with Silicate Networks: Sustainable Hybrid Materials with Tunable Properties

The development of sustainable organic–inorganic hybrid materials with a molecular level of covalent integration remains a major challenge. Here, we report a one-pot synthesis of covalently integrated poly(α-lipoic acid)-silicate (PLAOH·SiO2) hybrid networks using α-lipoic acid, an abundant natural building block, and complementary silicate precursors. Strategic selection of silicate precursors enables direct Si–O–C covalent bonding with hydroxyl groups on the poly(α-lipoic acid) backbone, yielding molecularly integrated, single-phase hybrid materials across varied organic-to-inorganic ratios. Systematic compositional variation enables continuous tuning of mechanical properties (Young’s modulus: 0.94 ± 0.03 – 63.3 ± 5.67 MPa, Hardness: 1.14 ± 0.07 – 73.10 ± 8.81 MPa) while preserving optical transparency (>75% transmittance) and thermal stability (Td > 220 °C) across the entire series. The hybrid material can be reprocessed and chemically recycled to the monomer. This provides a practical synthesis of sustainable hybrid materials with tunable mechanical properties, addressing critical needs in sustainable advanced materials manufacturing.