Preparation And Functionalization Of Acrylic Polymer/PTFE Composite Fibers

In order to achieve effective treatment of dye wastewater,the copolymer of acrylic acid(AA)and hydroxyethyl methacrylate(HEMA)was synthesized via precipitation polymerization.The spinning solution was prepared by dissolving the copolymer with dilute sodium hydroxide aqueous solution as solvent.The polytetrafluoroethylene(PTFE)emulsion was then added and ultrasonically dispersed into the above spinning solution.The newly-prepared dispersion was subsequently spun into fiber through wet spinning with dilute sulfuric acid as a coagulant.The wet-spun fiber was used as a carrier to immobilize iron ions by simple impregnation,and erythritol was simultaneously introduced into the fiber as a crosslinking agent during impregnation,then a composite fiber catalyst was fabricated by sequentially conducting crosslinking and sintering.The results showed that the construction of the crosslinked structure could effectively improve the water swelling resistance of the fiber,and PTFE component could significantly improve the hydrophobicity of the fiber.Under the synergistic effect,it can effectively inhibit the elution of iron ions,and give the composite fiber a very stable activity to catalyze hydrogen peroxide to oxidatively decolorize methylene blue(MB).During nine cycles,the composite fiber could completely decolorize MB within one minute and didn’ t show any attenuation in MB decolorization efficiency.In the ninth cycle,the composite fiber still could reduce total organic carbon of MB solution from the original 18.3 mg/L to 10.3 mg/L.Besides Fenton method,adsorption method is also considered to be a very promising method for dye wastewater treatment.In order to endow PTFE-based fiber with the function of adsorbing dye,so as to apply PTFE fiber to adsorb dye in harsh environment,Fe OOH sol was firstly prepared,then poly(acrylic acid-co-hydroxyethyl methacrylate)/PTFE composite fiber was swelling modified by Fe OOH sol to make it have hydrophilic points.Hydrophobic fiber with porous structure was prepared by sintering to endow it with dye adsorption characteristic.The results showed that the fiber had high porosity and large specific surface area,which mainly depended on Van der Waals force to adsorb dye.The adsorption capacity of MB could reach 155 mg/g at equilibrium.During nine cycles,the fiber could remove 90% of MB within 90 minutes.In addition to MB,the fiber also had the capability to adsorb other dyes.In the process of recycling the fiber to adsorb other dyes,the removal efficiency of cationic blue or cationic brilliant red could reach 90% within 90 minutes.