•A fluorine-free polymeric water-repellent agent PIT is designed and synthesized to fabricate superhydrophobic fabrics.•The resultant superhydrophobic fabric exhibits greatly improved durability.•Excellent water-repellency property similar to lotus leaves could also be achieved.A non-fluorinated polymeric alkylsilane, poly(isobutyl methacrylate-co-3-methacryloxypropyltrimethoxysilane) (PIT), is designed and synthesized to replace the commercial long-chain perfluoroalkylsilane (FAS) water-repellent agent. The superhydrophobic polyester fabrics are prepared by anchoring sol-gel derived silica nanoparticles onto alkali-treated polyester fabric surfaces and subsequently hydrophobilizing with PIT, using FAS as control. The surface chemical composition, surface morphology, wetting behavior and durability of the modified polyester fabrics are characterized by scanning electron microscopy (SEM), X-ray photoelectron spectrophotometer (XPS) and video-based contact angle goniometer, respectively. The results show that a porous silica layer could be successfully fabricated onto the surface of polyester fabric through base-catalyzed sol-gel process with tetraethoxysilane (TEOS) as precursor, incorporating additional nanostructured roughness essential for superhydrophobicity. At the same time, such a silica primer layer could provide both secondary reactive moieties (−Si − OH) for the subsequent surface hydrophobization and acceptable adhesion at the silica-polyester fabric interface. When silica modified polyester fabric (SiO2@ fabric) is hydrophobized by PIT solution (10 mg/mL), excellent water-repellency could be obtained. The water contact angle is up to 154° and the sliding angle is about 5°. Compared with small molecule water-repellent agent FAS, PIT modified SiO2@ fabric exhibits greatly improved solvent resistance under ultra-sonication, abrasion and simulated laundering durability. The anti-stain property of PIT-modified SiO2@ fabric is also evaluated by using different aqueous colored solutions.Download high-res image (164KB)Download full-size image

One-pot synthesis of organic–inorganic hybrid materials under light requires specific photoinitiating systems which are able to release several different initiating species after light absorption. In this paper, the reaction mechanism of a photocyclic three-component initiating system based on isopropylthioxanthone as photoinitiator and an iodonium salt and a thiol as co-initiators was studied. It is shown that this system enables simultaneous release of both radicals and protons which are able to initiate a free radical photopolymerization and the hydrolysis–condensation of a sol–gel network, respectively. Time-resolved investigations by laser flash photolysis show that the initiating species are produced within two concomitant cyclic reaction mechanisms depending on the relative quantities of the co-initiators. Protons resulting from the secondary dark reaction of the photocyclic systems are detected at the microsecond scale by means of a proton-sensitive molecular probe, and corresponding quantum yields are measured. Finally, synthesis of organic, inorganic, and hybrid materials under LED light at 395 nm is evaluated with respect to the mechanistic considerations demonstrating the dual initiating character of the system.