Design And Synthesis Of Amphiphilic Functionalized Polypropylene Fibers And Their Adsorption Properties

With the concept of green chemistry rooted in the heart of people,the use of clean,efficient and recyclable novel carrier materials has become the focus of research in the field of green chemistry.In particular,polypropylene and polyacrylonitrile fibers with unique properties of low cost,easy modification,good recyclability,high mechanical strength and good stability have attracted significant attention.From the prospective of application,the design of functionalized adsorption materials with specific structures based on structural characteristics of the target pollutants is the most important aspect.Therefore,in this thesis,a series of amphiphilic polypropylene functionalized fibers were designed and synthesized by introducing amphiphilic functional groups on the surface of polypropylene fibers to achieve synergistic adsorption and removal of parabens compounds.In this work,polypropylene functionalized fibers PP_A-PF-C_n(n=4,8,12)were prepared by a simple three-step modification reaction,and then determined by a series of characterizations.Firstly,the effects of the structure of functionalized fibers on the adsorption properties were tested.The results show that the amphiphilic functionalized fiber PP_A-PF-C_n(n=4,8,12)can selectively adsorb parabens,and the fiber PP_A-PF-C₁₂ has the strongest adsorption capacity.This is because the amphiphilic fibers can selectively bind the similar part of parabens through hydrophobic and hydrogen bond interactions to achieve an optimal adsorption effect.Secondly,the first-order kinetic model,second-order kinetic model,Weber-Morris intraparticle diffusion model,double exponential model,Freundlich model and Langmuir model were used to systematically study the kinetics and isotherm of the adsorption process.Finally,the recycling performance of the fiber was investigated.Under the flow condition,the removal rate of fiber PP_A-PF-C₁₂ is still higher than 90%after 10 cycles.In addition,we prepared a series of functionalized polyacrylonitrile fibers with adjustable surface hydrophilic/hydrophobic microenvironment by introducing different polar functional groups.The fiber catalysts were characterized by FTIR,elemental analysis,SEM,XRD and TGA,which confirms the successful preparation of fiber.The catalytic activity of hydrophilic and hydrophobic functionalized fibers was investigated by a three-component reaction of p-chlorobenzaldehyde,malononitrile and 1-naphthol in water.The results show that hydrophobic fibers have better catalytic performance than hydrophilic fibers.