Energy-Efficient Synthesis of Organic-Inorganic Hybrids Through Polymer Complexation

Vapor phase infiltration (VPI) processing is an emerging gas-phase method for producing organic–inorganic hybrid materials. This method involves the diffusion of vapor phase metalorganic precursors into organic polymers, leading to their transformation into versatile organic-inorganic hybrids. These materials have a broad range of applications such as lithography patterning, freestanding film modification, and the manufacturing of foams and textiles. Nonetheless, a notable challenge in this method is the requirement for highly pyrophoric and expensive precursors such as trimethylaluminum (TMA) to diffuse into the polymer chains and the bulk of material. These constraints necessitate a transition towards more environmentally friendly and economically viable alternatives for VPI precursors. To address these limitations, we introduce a novel approach for depositing metalorganics into polymer films. By utilizing elements with accessible d-blocks, such as silicon, which can readily form dative bonds with electron-donating polymers like poly(4-vinylpyridine) (P4VP), we achieve effective infiltration of metalorganic precursors into polymer chains to create organic–inorganic hybrid complexes at ambient room temperature, while minimizing the use of toxic gases. The formation of the polymer complexes is verified using Solid-State Nuclear Resonance Magnetic (SSNMR) technique and X-ray Photoelectron Spectroscopy (XPS). Spectral reflectance of P4VP films post reaction showed 30-35% film growth for different silane precursors including tetrachlorosilane, trichlorosilane and dichlorosilane, consistent with thermogravimetric analysis (TGA). We observed film growth in high molecular weight precursors, albeit with a slower growth rate.