| The polymer materials are extremely important position in social's development,since the discovered and utilized of oil,the polyesters and polyurethanes obtained from petroleum resources that used to construction,electronic appliances,automobile industry,packaging and other fields widely.However,the petroleum resources be used massive that has brought a serious of question of environmental pollution and energy crisis.It is imminent what choose biomass resources that green and environmentally friendly renewable to replace petroleum resources.Lignocellulose is the most abundant biomass resource in nature,we can obtained a series of bio-based platform compounds through chemical and biological conversion techniques from lignocellulose,such as vanillin,levulinic acid,5-hyroxmethylfurfural.These compounds has highly reactive functional groups that provide the possibility for the synthesis and application of biobased polymer functional materials,this is great significance of preparation the polymer materials for green and sustainable development.In the paper,a series of bio-based monomers were designed and synthesized used the products obtained by conversion of lignocellulose as raw materials,and a series of bio-based polymer materials are prepared through an efficient polymerization strategy.We characterized the structure of these bio-based monomers and polymers by nuclear magnetic resonance(NMR)and Fourier infrared spectroscopy(FTIR),and characterized the propertied of these polymers by thermogravimetric analysis(TGA),gel permeation chromatography(GPC),differential scanning calorimetry(DSC)and X-ray diffraction(XRD).On the one hand,we made full used of the derivatizable hydroxyl and aldehyde groups on vanillin,and used a green and environmentally friendly catalytic method to prepared vanillin-based diol monomers.there are a series of bio-based polyesters were prepared by polycondensation of vanillin-based diol monomers with diacid chloride,a series of bio-based polyurethanes were prepared by addition polymerization of diol monomers with diisocyanate.The yield of polymers in the range of 62 % to 97 %,the molecular weight of the polymers are ranging from 17000-40000 g /mol.We found that the decomposition temperature reach up to 293 ? of the polymers at 5 wt%,these polyesters and polyurethanes have Tg in the range of 16.2 to 81.2 ? and 11.6 to 80.4 ?,respectively.The higher reaction activity of the alcoholic hydroxyl group can improve the yield and molecular weight of the polymers compared with the phenolic hydroxyl group.We prepared a fully bio-based polyester containing furan groups and vanillin groups,its thermal properties are similar to benzene ring-based polyesters.On the other hand,we prepared fully bio-based polymerizable monomer containing internal double bonds by aldol condensation reaction that use vanillinderivatives and ?-H-containing bio-based monomers as raw materials,then we made fully bio-based polyesters materials by transesterification polymerization.We were obtained the saturated full bio-based monomers by hydrogenation reaction of monomers containing internal double bonds,and prepared the saturated polyester materials,this polyester has the best thermal stability,and the temperature is 316 ? of a weight loss at 5 wt%.We study the impact on the preparation of full bio-based polyester through different catalytic systems,and found that Zinc acetate dihydrate and TBD are the most effective catalysts;we founded a green and environmentally friendly method for the post-treatment of strong organic base-catalyzed polymerization reactions,and achieved results comparable to traditional methods.The study provides a feasible strategy for the synthesis of bio-based polymers materials.Especially,the green post-processing method of polyester provides a new scheme for the preparation and research of full bio-based polyester materials,and has important reference value and scientific significance. |
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