Preparation of tetrafluoro-λ 6 -sulfanyl bridged-bonding perfluoroalkyl phenylethyltrichlorosilane and its application on fabric finishing
By Guangtao Chang, Lei Chen, and Zhanxiong Li
Materials Res. Ex.
July 28, 2020
In this study, one novel perfluoroalkyl silane with tetrafluoro-λ6 -sulfanyl bridging group named 4-(Tridecafluorohexyl sulfur tetrafluoride) Phenylethyl trichlorosilane (PFSTS)was successfully synthesized via fluorination and hydrosilylation. The structure was characterized by FT-IR and NMR Then, the product and the control subject 1H,1H,2H,2H-perfluorooctyltrichlorosilane (PFOTS)were finished onto PET fabrics through the method of dip-and-pad. The wettabilities of the treated PET fabrics were characterized by Water Contact Angles(WCA) and surface free energies measurements. X-ray Photo electron Spectroscopy (XPS)was used to validate the attachment, together with the chemical composition of the polymers on the surface of treated PET fabrics. The WCAs of [email protected] and [email protected] were 142.2°, 137.3°, while the WCA of untreated PET fabrics is 120°in general, indicating that PFTOS and PFSTS can provide good hydrophobicity by finishing PET fabrics. After the 48 h exposure to accelerated agingUV irradiation, sample of [email protected] show a decreased CA value by 12.5% from 137.3°to 120.1°, while for sample of [email protected], the percentage of reductionis only 2.8%. It was found that the perfluoroalkyl trichlorosilane that containing –SF4– bridged group exhibited excellent water-repellency properties and had higher potential to UV degrade as possessing weak bond energy of C–S bond, so the PFSTS might act as an eco-friendly alternative to carbon-chain perfluoroalkyl derivatives in water-repellency areas