Study On Hydrophilic/Hydrophobic Modification And Properties Of Tannic Acid On Textile Materials

With the continuous improvement of people’s living standards,people have put forward higher requirements for the functionality of textile materials.At present,the research and application of functional textile materials have been widely concerned by researchers,such as hydrophilic/hydrophobic,flame retardant,radiation protection and so on.Among them,hydrophilic/hydrophobic textile materials represent broad application prospects in oil-water separation,self-cleaning,anti-corrosion,anti-pollution and other fields.Tannic acid（TA）is one of the polyphenol compounds extracted from plant tissue.Which not only has a wide range of sources,but also shows unique chemical properties.It provides a new idea for preparing high performance hydrophilic/hydrophobic textile materials and broadening the application range of materials.In this paper,tannic acid was used as the main modification material,and a series of typical textile materials,including cotton fabric,polyester fabric,nylon fabric,and cellulose acetate electrospinning menbarent and its hydrolyzed products,were selected as the base materials.The preparation process and influencing factors of tannic acid surface modification on the selected base material were systematically studied by dipping method.The surface hydrophilic/hydrophobic properties,mechanical properties and thermal stability of the obtained materials were characterized.The applications of the modified materials in oil-water separation and oil/water preservation were preliminatively discussed.Finally,the modification effect of tannic acid on the selected textile materials was analyzed and compared.The main research is as follows:（1）The hydrophobic modified cotton fabric was prepared by dipping method using cotton fabric as base material,TA as main modifier,Fe³⁺as stabilizer and reinforcing agent.The effects of pH value of buffer solution,tannic acid concentration,TA/Fe³⁺concentration ratio,reaction time and other factors on the surface hydrophobic properties of modified cotton fabric in alkaline environment were investigated,and the optimal preparation conditions were obtained.The test results indicate that the surface water contact angle of the modified cotton fabric prepared by coordination between TA and Fe³⁺was up to 142.5°,and the mechanical properties and thermal stability were better.（2）Two hydrophilic modified fabrics were prepared by using polyester fabric and polyamide fabric as the base material respectively,TA as the main modifier,3-aminopropyltriethoxysilane（APTES）as the enhancer and Fe³⁺as the stabilizer.The effects of pH value of buffer solution,tannic acid concentration,APTES concentration,TA/Fe³⁺concentration ratio,reaction time and reaction temperature on the surface hydrophilicity of modified fabric were investigated,and the optimal preparation conditions were obtained.The test results indicated that the interaction of TA,APTES,and Fe³⁺could help them adhere to the surface of the two fabrics and improve the hydrophilicity of polyester and nylon fabrics.Both mechanical properties and thermal stability were enhanceed to some extent.（3）Hydrophilic modification of electrospun cellulose acetate nonwoven fabric composed of nanofibers and hydrophobic modification of hydrolyzed cellulose nonwoven fabric were carried out.The effects of pH value of buffer solution,tannic acid concentration APTES concentration,TA/Fe³⁺concentration ratio,reaction time and reaction temperature on the surface hydrophilicity of modified fabric were investigated and the optimal preparation conditions were obtained.Comparison of hydrophilic/hydrophobic performance test results was found that tannic acid showed better hydrophilic modification effect on cellulose acetate.（4）The oil-water separation properties,oil absorption and oil retention properties and water absorption and water retention properties of the obtained textile materials after hydrophilic/hydrophobic modification were explored.The results indicated that in terms of hydrophobic modification,the oil water separation efficiency of the cotton fabric modified with tannic acid could reach 90.1%,and the oil absorption and oil retention performance was good;in terms of hydrophilic modification,the modified nylon fabric and nylon fabric showed good oil-water separation effect,while the oil-water separation efficiency of the cellulose acetate nanofiber membrane modified with tannic acid could reach 97.9%,and it reusability was good.It can be seen that tannic acid is more suitable for hydrophilic modification of textile materials in the field of hydrophilic/hydrophobic modification.