Study On The Cross-linked Esterified Starch Of Microwave Synthesis And Polysaccharide Solution Of The Esterification, Graft Copolymerization

Starch as a cheap, easily biodegradable and no environmental pollution natural polymer has become an important raw material and widely used in many areas through starch modification. Over the years, the research and development of starch take much attention around the world. Biomass is the most widespread material and an important renewable energy. The biomass liquefaction products-polysaccharide solution is environmentally friendly production and an important raw material.This study was based on starches, polysaccharide solution as research object. The research contains two aspects. The first one is the esterification reaction of starch and maleic anhydride in the microwave conditions. Second is esterification and grafting copolymerization reaction of polysaccharide solution with oxalic acid and acrylic monomers, respectively.In the first research aspects, we use starch and maleic anhydride to synthesis maleic acid starch under the influence of the microwave. The study is mainly focus on a variety of factors that affect the esterification reaction of starch and maleic anhydride in the microwave conditions. In this part, we selected optimum reaction conditions of starch with maleic anhydride through analysis esterification rate by the acid-base titration method. The result show that the esterification degree is 29.73% under the condition of 110 W microwave power, 10 g starch, 4 g maleic anhydride, 6 times microwave reaction and 2min reaction time. In addition, we selected the optimal reaction conditions of starch and epichlorohydrin through these two compounds'settlement plot of cross-linked. We found that the maximum cross-linking is happen when 5 g Starch and 0.15 mL epichlorohydrin react 5 hours. Then cross-linking starch and maleic anhydride will react. At last, we determined the optimum conditions for this microwave condition based on the degree of esterification. Final result show that under the reaction condition of microwave power 110W, 10 g cross-linking starch, 4g maleic anhydride, reaction 2 times and 6 minreaction time, the degree of esterification is 22.03%. Moreover, we analysis the product's structure and characterization it by infrared spectroscopy.In the second research aspects, the raw materials are polysaccharide solution and oxalic acid. When the temperature was 85℃, thirty gram polysaccharide solution reacted with 1mL, 3.00 mL, 5.00 mL, 7.00 mL, 9.00 mL of 20% mass fraction of oxalic acid, respectively. Through the smear and intensity of the peak in the IR spectrum, we found that the acid has been excessive in such above reaction volume. Also we analysis the reactant and product's structure and characterization it by infrared spectroscopy and carbon spectra.In addition, we study that the polysaccharide solution reacted with grafting copolymerization of acrylic monomers. Such monomers were made up by acrylic acid, methyl acrylate, butyl acrylate, methyl methacrylate and ethylhexyl acrylate in accordance with a certain proportion. The result of this study concluded the optimum amount of reaction product of water resistance as the basis. That is 30 g polysaccharide solution and 5 mL monomer. Also we analysis graft copolymer product's structure and characterization it by infrared spectroscopy.