Heat resistance and surface properties of polyester resin modified with fluorosilicone

In this work, fluorosilicone modified polyester resin (FSP) prepared from polyester (PET) and fluorosilicone resin (FS) with excellent heat resistance and surface wettability was reported. FS was synthesized by hydrolysis and condensation reaction of 1H,1H,2H,2H-perfluoroalkyltriethoxysilane (FTEOS), methyltriethoxysilane (MTEOS), phenyltriethoxysilane (PTEOS), dimethyldimethoxysilane (DMDMOS), and diphenyldimethoxysilane (DPDMOS). The surface chemical composition and morphology of the resins were determined by Fourier transform infrared (FT-IR), X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM). The surface wettability and thermal property of the FPS films were studied via contact angle measurements and thermogravimetric analysis (TGA), respectively. The modified resin displayed excellent heat resistance, water and organics repellence due to the native high bond energy and low surface free energy of fluorosilicone. For the FSP resin containing 50 wt% of fluorosilicone resin (F5SP50), the starting decomposition temperature Td10 (10% weight loss) reached 360 °C, which was 40 °C higher than that of neat PET. The residual weight at 700 °C was also remarkably increased. Moreover, hydrophobicity, oleophobicity and hardness of FSP films were enhanced by optimizing the addition of fluorosilicone in polyester resin. The prepared fluorosilicone modified polyester resin has a great potential in the application of high-temperature coating.