| Organosilicone has been widely used in many fields due to the excellent properties such as low surface free energy,high and low temperature resistance,chemical stability and biocompatibility.Organochlorosilanes(RnSiCl4-n,n=0,1,2,3)were very reactive,and the surface of the substrate could be silanized by a simple liquid phase reaction,giving the treated surface special properties.In this dissertation,different functional coatings were prepared on the surface of PET fabric by liquid phase method using different organictrichlorosilanes as raw materials,the effects of process conditions on the chemical composition,morphology,and wettability of the coating were studied,and the potential applications of the resulted textile were discussed.The following three aspects were specifically explored:(1)The preparation of superhydrophobic polyester treating by alkyl trichlorosilane via liquid phase methodA latex was synthesized by emulsion polymerization using vinyl acetate as the main monomer.Polyester fabric was dipped into emulsion and maintained a certain water content.Vinyl trichlorosilane(TCVS),phenyl trichlorosilane(PTS),and methyl trichlorosilane(MTS)were hydrolyzed and crosslinked on the surface of the fiber to form a hydrophobic coating with a certain rough structure,respectively.The effects of different processes on the surface morphology and wettability of the fiber were investigated,and the process conditions were optimized.It was found that different alkyl groups had a great influence on the morphology and wettability of the coating.The coating treated by TCVS and MTS had a filiform and spherical structure,which had good superhydrophobic property and could be used as self-cleaning or selective oil absorption materials,and the coating treated by PTS has a porous structure,while its hydrophobicity was slightly lower than that treated by TCVS and MTS.The hydrophobic stability of the coating was tested by sandpaper rubbing,tape sticking,and washing,and the results showed good stability.Due to the tight organosilicone coating formed on the fiber surface,the air permeability of the fabrics after the treatment decreased,while the process had little effect on the whiteness and strength of the fabric.(2)The preparation of hydrophobic and oleophobic polyester by fluorine-containing alkyltrichlorosilaneThe surface of the fiber in PET fabrics was coated with fluorine-containing silicone by liquid-phase method using trifluoropropyltrichlorosilane(PFPTS),tridecylfluorooctyltrichlorosilane(PFOTS),and heptafluorodecyltrichlorosilane(PFDTS)as raw materials.As the length of the fluoroalkyl chain increased,the hydrophobicity of the coating also increased.However,fluorine-containing alkyltrichlorosilane could not form a rough structure on the fiber surface independantly except a smooth film.Introduction tetrachlorosilane(TCS)and controlling the ratio of silane monomers can achieve a variety of rough surface,as well as obtain the wettability transitions from the surface to hydrophilic and lipophilic to superhydrophobic and oleophobic.The wettability,stability and fabric properties of the coatings prepared by TCS/PFOTS were found to be covered with low surface energy microspheres,which provided the excellent hydrophobicity and oleophobicity.The coatings had little effect on the whiteness and breaking strength of the fabric,and the softness of the TCS/PFOTS coated fabric was better than that of PFOTS.(3)Synthesis of tetrafluorosulfanyl linked perfluoroalkyltrichlorosilane and the application on fabric finishingp-(tridecafluorohexyl tetrafluorosulfide)-phenylethyl trichlorosilane was synthesized by using 4-bromothiophenol and trifluoro-l-iodohexane as raw materials through radical substitution,oxidative fluorination,carboanion nucleophilic substitution of Grignard reagent and hydrosilylation,and the traget product was characterized.The PET fabric was treated with the as prepared fluoroalkyltrichlorosilane via the liquid phase method.The elemental composition and morphology of the fiber surface before and after finishing were detected by XPS,SEM.Compared with the PFOTS coating,it was found that the surface contact angle of the tetrafluorosulfanyl linked perfluoroalkyltrichlorosilane coating decreased significantly more than that of the PFOTS coating after UV light irradiation,and the surface free energy increased significantly.This showed that-SF4-perfluoroalkyl was a kind of sulfur heterochain perfluoroalkyl which was easy to UV photo degradation.It was observed by SEM that the roughness of perfluoroalkyl coating of the tetrafluorosulfanyl linked perfluoroalkyl decreased due to UV irradiation,and the perfluoroalkyl polysiloxane film was broken partly,which further proved that tetrafluorosulfanyl linked perfluoroalkyl was easily photodegradable and was a potential material with low surface energy. |
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