Abstract: In polymer hybrid materials, a small quantity of inorganic components can significantly enhance physical properties such as mechanical and dielectric energy storage. However, traditional processing strategies like solution blending present complex procedures, high carbon emissions, and scalability challenges. This study employs a dual in situ strategy to directly synthesize polyester hybrid materials from organic-inorganic monomers, meanwhile spectroscopic analysis is utilized to investigate molecular structural evolution from monomers to the hybrid materials. Results demonstrate polyester in situ polymerization synchronizes with in situ growth of inorganic components during synthesis. More importantly, molecular-scale interdiffusion between polymer chains and inorganic components establishes a characteristic organic-inorganic hybrid structure. Tensile strength and elongation at break increase from 58.23 MPa and 17.14% for pure polyester to 68.98 MPa and 33.69%, respectively. The dielectric constant reaches approximately 2.1 times to that of pure polyester, while breakdown strength improves from 235.03 MV/m to 418.38 MV/m at 100°C. Consequently, the energy storage density surges from 5.38 J/cm3 to 10.64 J/cm3, representing a 97.77% enhancement. This work provides a low-carbon fabrication strategy for high-performance polyester hybrid materials, which expands functional development avenues and application potential for polyester-based materials.

Key words: Polyethylene terephthalate, Organic and inorganic composite, Hybrid material, Mechanical property, Dielectric property