Study On Synthesis And Polymerization Of Bio-based Furan Monomer

With the increasingly serious environmental pollution problem and the rapid consumption of traditional petrochemical raw materials,it is becoming more and more urgent to develop renewable and environmentally friendly resources for the chemical and energy industry.Biomass raw materials can be obtained from agricultural waste and energy crops,and it is widely distributed and diverse in nature.Therefore,biomass resources are considered to be the only renewable organic carbon resources with wide application prospects,and will become important raw materials for the preparation of organic chemicals and polymer materials.AS the important energy,biomass resources are closest to human production and life.They come from nature and return to nature.The realization of biomass energy conversion and green recycling can play a key role in sustainable development of the world economy and energy environment.5-Hydroxymethylfurfural and furfural are important biomass platform molecules.5-Hydroxymethylfurfural and furfural and their derivatives can also be used to synthesize bio-based furan ring polymers with different structures through oxidation,reductive hydrogenation,amination,etc.5-Hydroxymethylfurfural and furfural can also be converted into multi-substituted furancarboxylic acid derivatives through oxidation and structural modification.If such compounds are converted into high-value-added fine chemicals,that will greatly improve the conversion and utilization of biomass raw materials,and a new route will be opened for applications of bio-based raw materials.Bio-based furan ring polyamide fiber has the functions of strong rigidity,corrosion resistance,high temperature resistance,sterilization,degradability and strong processability.It has wide application prospects in packaging materials,textile materials,human tissue repair materials,engineering plastics and other fields.However,existing bio-based furan ring polyamide also face shortages of varieties,incomplete product performance,and lack of independent intellectual property rights,which seriously restrict the development of China's military science and technology.In the“Industrial Structure Adjustment Guidance Catalogue(2019 Edition)”published by the National Development and Reform Commission on November 6,2019,the development,production and application of new fibers such as bio-based furan rings were included in the encouraged product catalogue for the first time.The development of the furyl polyamide industry ushered in spring.2,5-furandicarboxylic acid(FDCA)has been proved to be one of the most important bio-based furan ring polymerization monomers,but its synthesis method still faces many challenges.In this paper,we prepared a high-purity bio-based monomer FDCA by using 5-hydroxymethylfurfural with high selectivity and high yield.In view of the important application value and broad industrial prospects of bio-based furan polyamides,the types and properties of traditional monomer compounds are far from meeting the market demands.Therefore,the development of novel bio-based polymeric monomers with unique properties is another challenge for the academic community.Furan acrylic compound is a potentially important bio-based monomer.In addition to its rigidity,strong aromaticity,antibacterial and degradable properties,the presence of conjugated double bonds is another important advantage.On the one hand,the introduction of carbon-carbon double bonds into the molecular structure of high-molecular polymers is an important strategy to improve the properties of materials.The presence of conjugated double bonds can effectively adjust the rigidity,conductivity,and abrasion resistance of polymer materials.On the other hand,polymer monomers containing conjugated double bonds have excellent chemically activity because they contain double bonds in the molecule,which provides more space for the designing of the molecule structures.It can introduce new branches to monomers through addition reactions and further modify the structures.Therefore,polymer materials synthesized from bio-based furan acrylate monomers may have more excellent mechanical,thermal,and physical properties.In summary,the design and synthesis of new furan acrylic monomers and their polymers has important research value for the development of organic functional materials and the high value-added utilization of biomass raw materials.However,in the existing preparation methods,raw materials are derived from non-bio-based materials,but the source of the raw materials is limited.Otherwise,reactions required multi-steps,harsh conditions and high cost.A relatively inexpensive ruthenium-catalyzed reaction system was developed in this paper to convert bio-based furan carboxylic acid compounds into multi-substituted furan acrylic polymer monomers in a one-pot process under milder conditions.In this paper,based on the improvement of traditional monomer technology and the preparation of new furan acrylate monomers,2,5-furandicarboxylic acid was selected as the monomer raw material for the first time to prepare a new type of bio-based furan polyamide fiber with independent intellectual property rights.Its performance and application are studied.In the first chapter,the composition and source of biomass are briefly described.The preparation methods of 5-hydroxymethylfurfural and furfural was summarized.Subsequently,we introduced the methods and types of conversion 5-hydroxymethylfurfural and furfural to furanyl polymer monomers and furancarboxylic acids.In the second chapter,a new homogeneous and recyclable heterogeneous PdCoBi/C catalyst system was developed to oxidize 5-HMF to methyl 2,5-furandicarboxylate(DMFDCA)under normal pressure,FDCA is prepared with high yield through oxidative esterification system hydrolysis.The reaction uses Pd/Co(NO3)2/Bi(NO3)3 as catalyst,choosing potassium carbonate as base,and methanol is used as a solvent under 60?.When using Pd/Co(NO3)2/Bi(NO3)3 homogeneous and heterogeneous catalyst systems,the highest DMFDCA yields are 93%and 96%,respectively.FDCA yield can reach 92%under heterogeneous catalyst systems.Heterogeneous catalysts can be used 5 times,the experimental results are demonstrated through the characterization of the catalysts.Substrate expansion shows good compatibility of the catalytic system.In the third chapter,furoic acid and butyl furan acrylate are used as model substrates.Different effects such as catalyst,oxidant,alkalis and solvent are examizined.In this paper,direct alkenylation and decarboxylation-alkenylation of furoic acid derivatives to furanacrylate were carried out by efficient[Ru(p-cymene)Cl2]2 catalyst.A new furan acrylic bio-based polymerized monomer was prepared by the reaction system.[Ru(p-cymene)Cl2]2 was used as catalyst and K2HPO4 was used as base,chosing DMF as solvent and Cu(OAc)2 as oxidant.Decarboxylation or carboxyl group retention was achieved through simple temperature adjustment.Up to 76%and 80%isolated yield of furanacrylate by direct alkenylation and decarboxylation-alkenylation of furoic acid derivatives were obtained at 80? and 125?,respectively.A series of furan propenyl polymer monomers were efficiently and green synthesized by the "one-pot method".Finally,the reaction mechanism was studied through deuteration experiments and control experiments.In the fourth chapter,We choose FDCA derivatives 2,5-furandiyl chloride(FDCl)and 4,4-diaminodiphenyl ether(ODA)as monomers,and DMAC was used as a solvent to rapidly synthesize high molecular weight bio-based polymers without catalyst and other additives under mild conditions.The weight average molecular weight of POF is 1044109 g/mol,and the number average molecular weight is 616712 g/mol.Spin experiments were performed on furan polyamide(POF)and processed into bio-based furan polyamide fibers.Differential scanning calorimetry(DSC),thermogravimetric analysis(TGA),tensile test and dynamic mechanical analysis(DMA)test show that POF has outstanding thermal stability and mechanical properties.The glass transition temperature of POF is 280.33?,initial decomposition temperature of POF is 388.12? and the Maximum decomposition temperature was 455.26?.The Young's modulus of POF fiber with a fineness of 200 D is 3622.10 MPa,the tensile strength is 119.20 MPa,and the elongation at break is 21.56%.These results pave the way for POF to be used as high-performance special engineering plastics.In the fifth chapter,the full text was summarized and forecasted.In summary,this paper mainly studies the preparation and polymerization of bio-based furan ring polymerized monomers.The Pd/Co/Bi catalyst system was developed,and the bio-based monomer FDCA was efficiently synthesized.Alkenylation of furan carboxylic acid compounds was achieved by ruthenium-catalyzed "one-pot method",which provided a new strategy for the preparation of multi-substituted bio-based furan acrylic polymer monomers and fine chemicals.Finally,a high-molecular-weight bio-based furan ring polyamide POF was synthesized using FDCA as the raw material,POF exhibited outstanding thermal stability and mechanical properties.