Fabrication And Properties Of Hypercrosslinked Polymers Based On F-C Reaction Of Vinyl Group

Microporous organic polymers（MOPs）have good properties such as large specific surface area,strong modification,diverse preparation methods and high chemical and physical stability,showing great potential in the fields of gas adsorption,catalyst carrier,environmental analysis and drug release.Hypercrosslinked polymers（HCPs）not only have high specific surface area,modification and good thermal stability,but also have the advantages of a wide range of monomer sources,simple synthesis conditions,showing great industrial potential.HCPs are the first to achieve industrial production of microporous organic materials.The unique advantages of hypercrosslinked polymers have attracted extensive interest of researchers.In recent years,reports on the preparation and synthesis of hypercrosslinked polymers have emerged one after another.But so far,hypercrosslinked polymer is often based on the condensation of the preparation,in the process of synthesis tend to bring a small molecular compound with pollution removal,thus cause pollution and damage to the instrument and environment.It is not a green synthetic route and also limits the choice of monomers and crosslinking agent.In this paper,Friedel-Crafts alkylation based on double bonds was proposed to replace the widely used condensation reaction to prepare hypercrosslinked polymers.In order to obtain high specific surface area microporous polymers,reduce environmental pollution and expand the selection of monomers and crosslinking agents.The specific research contents of this paper are as follows:Fabrication of divinyl benzene based hypercrosslinked polymers and H₂storage.A hypercrosslinked microporous polymer with a specific surface area of 931m²/g was prepared by double bond F-C addition polymerization using divinylbenzene（DVB）as monomer and anhydrous ferric chloride（Fe Cl₃）as catalyst.The effects of solvent type,polymerization temperature and polymerization time on the reaction were investigated.The structure of hypercrosslinked divinylbenzene（HCPDVB）was characterized by ¹³C-NMR,FT-IR and XPS,and the process of DVB F-C addition self-polymerization was confirmed.Compared with PDVB,the mechanism of DVB F-C addition polymerization was proposed.In addition,DVB was used as A double bond crosslinking agent to cross phenylalanine（Phe）,bisphenol A（BPA）and other phenyl monomers that do not have self-polymerization ability,in order to verify the universality of DVB as A new double bond small molecule crosslinking agent.Self-addition of biomass olefinic compounds.sing styrene,eugenol,isoeugenol and other phenyl monomers with a single double bond that can be extracted from biological sources,using Fourier addition polymerization for self-polymerization,hypercrosslinked microporous materials were obtained in one step.Using styrene,eugenol,isoeugenol and other phenyl monomers that can be extracted from biological sources,using F-C addition self-polymerization,hypercrosslinked microporous materials were obtained in one step.The effect of monomer type and input amount on the pore properties and structure was studied:with the increase of monomer input amount,the pore properties of the product would decrease,but the molecular structure of the product would not be affected.In addition,the effects of polymerization time and catalyst input on molecular weight of styrene were studied.Carbon areogels derived from expandable polystyrene（EPS）.HCPEPS were prepared by using EPS as the long chain monomer providing the benzene ring site,DVB as the crosslinking agent and Fe Cl₃as the catalyst.The product has a sixfold adsorption for toluene.In addition,carbon aerogel（CA）with surface area up to 910 m²/g was obtained by calcination at high temperature of HCPEPS.It provides a method to transform waste into treasure to solve white pollution,and verifies the reaction ability of DVB as a double-bond small molecule crosslinking agent to crosslink benzene ring containing polymer.Lignin extracted from biomass by DES and its hypercrosslinked aerogels.Lignin containing many benzene rings was extracted from corn cob by deep eutectic solvent method.Using lignin as a long chain matrix containing benzene ring,hemin as crosslinking agent and Fe Cl₃ as catalyst,hypercrosslinking polymer was prepared in one step by molten salt method.The effects of traditional solvent method and molten salt method on the properties of the products were investigated,and phenylalanine and lignin were added as comparison.