A High Fastness Of Bionic And Low Resistance Hydrogels Constructed On PET Fabric Surface By UV Technology

Kelp is an edible marine plant,and its natural biomorphology and surface structure determine that kelp can take root in the sea bed and grow stably in reefs and currents,which is largely related to the surface properties of kelp,and studies have shown that a biomass hydrophilic layer on the surface of kelp can largely reduce the frictional resistance at the solid/liquid interface,thus reducing the impact of currents on the kelp root system and stabilizing kelp growth.With the increase of people‘s marine activities and the development of competitive sports,more and more places need new diving equipment and swimming costumes,how to reduce the frictional resistance of diving equipment or swimming costumes in the water,reduce the physical exertion of users and improve the speed of competition is an interesting research topic.In this paper,three unsaturated monomers acrylamide(AAM),acrylic acid(AAC)and N-isopropylacrylamide(NIPAAM)were used as raw materials for polyester fiber woven fabrics,and unsaturated double bond compounds synthesized in the laboratory were used as fabric pretreatment agents to construct a kelp-like low friction coefficient hydrogel layer on the surface of PET fabrics by UV surface grafting,and the grafting of PET fabrics was The physical and chemical properties of the PET fabric before and after grafting were characterized,and the effect of different conditions on the resistance reduction performance of the hydrogel solid/liquid interface was investigated in order to prepare excellent resistance reduction textile fabrics for underwater surfaces.The main research contents and main findings of this paper are as follows:(1)Synthesis of resorcinol diglycidyl acrylate and introduction of double bonds on the surface of PET fabrics.Resorcinol diglycidyl acrylate containing unsaturated double bonds was obtained by ring-opening reaction using acrylic acid and resorcinol diglycidyl ether as raw materials,triethylamine as catalyst,and hydroquinone as blocking agent.The unsaturated double bond modifier was finished on the surface of PET fabric by high-temperature heat treatment to introduce unsaturated double bond groups on the surface of PET fabric and provide reaction sites for UV grafting hydrogel on the surface of PET fabric later.The best process for high temperature heat treatment of PET fabric is: resorcinol diglycidyl acrylate concentration of 10%,baking time of 4 minutes,and baking temperature of 130°C.(2)Photo grafting of different hydrogel layers on PET fabric surfaces.Three unsaturated monomeric acrylamide(AAM),acrylic acid(AAC)and N-isopropylacrylamide(NIPAAM)hydrogel layers were grafted onto the pretreated PET fabric surface under UV light irradiation conditions.Infrared spectroscopy tests showed that the monomers AAM,AAC and NIPAAM were successfully grafted to the fabric;scanning electron microscopy tests showed that the hydrogel layers on the fabric surface were rich in three-dimensional network pore structure,and super depth of field 3D optical microscopy showed that the hydrogel layers were uniformly smooth and transparent,and the fabric tissue pattern was clearly visible.The optimal process of photo grafting was that the maximum grafting rate could be obtained by UV light irradiation in a mixed solution with 10% monomer concentration and 1.2% photoinitiator 1173 concentration for 25 min.The effect of crosslinker concentration on the surface morphology and swelling properties of hydrogel layers on the fabric surface was investigated.The results indicated that the overall water absorption and swelling properties of PAAM,PAAC and PNIPAAM hydrogel layers decreased with the increase of crosslinker concentration,and the three-dimensional network pore structure gradually became smaller and the pore wall became thinner and thicker.The effects of temperature and solution environment on the water absorption performance of hydrogel layers were investigated,and the results indicated that the swelling properties of PAAM and PAAC hydrogel layers gradually increased with the increase of temperature,while the swelling rate of PNIPAAM hydrogel layer gradually became smaller due to its temperature sensitivity with the increase of temperature.The swelling properties of PAAC hydrogel layers decreased significantly with increasing ionic strength,and the swelling properties of PAAM and PNIPAAM hydrogel layers were less influenced by external ions.The dynamic water absorption and surface morphology of kelp were investigated,and the results showed that kelp has extremely high swelling performance,reaching 600% swelling rate in 20 minutes;the surface of kelp is a rough state of micro-nano composite structure,and the interior is a complex cavity structure with about 50 ?m pores,which is relatively large compared with the fabric indicating the hydrogel layer.(3)The grafted hydrogel layer on the fabric surface was firm and the network structure was stable.The friction coefficient of the hydrogel layer on the fabric surface was tested under different conditions using a rotational rheometer to observe the changes in friction properties and to analyze the factors affecting the friction behavior,and the main conclusions were as follows:(1)Under the same test conditions,the magnitude of friction coefficients of untreated PET fabric,PET-PAAM,PET-PAAC,PET-PNIPAAM and kelp are ?(PET)> ?(KELP)> ?(PET-PAAC)> ?(PET-PNIPAAM)> ?(PET-PAAM).The friction coefficient of PET-PAAM fabric is the smallest,which can reach 0.02,is about 85% lower than that of untreated PET fabric;compared with kelp,the friction coefficient is 17% of that of kelp.(2)Both temperature and solution environment have an effect on the friction coefficient of hydrogel layer,where the temperature-sensitive hydrogel layer PET-PNIPAAM becomes smaller with increasing temperature,and the friction coefficient of PETPAAC hydrogel layer increases significantly in simulated seawater solution.(3)The surface friction coefficient of hydrogel layer shows an overall increasing trend with the increase of cross-linking agent concentration;it increases with the increase of normal load;it will be affected by the synthetic substrate,and the surface friction coefficient of hydrogel synthesized on glass substrate is smaller than that of hydrogel layer synthesized on plastic substrate;the friction coefficient of hydrogel layer will be different with different fabric surface structure.