Study On The Preparation And Application Of Super Absorbent Polymer Made From Corn Starch-acrylic Acid Graft

In this paper,the corn starch-acrylic acid graft super absorbent polymer is prepared from corn starch as a raw material,N,N′-methylene-bisacrylamide as cross-linker, potassium persulfate as initiator agent by aqueous solution polymerization.persulfate hierarchy is a initiator with better efficiency and reproducibility,in the reaction with no dramatic changes in temperature, easier to control in industrial production; Production processess not demand nitrogen atmosphere and special equipment, simple process,less investment and low-cost,make a useful try in spread and apply for SAP.Firstly,preparation of process conditions to the corn starch-acrylic acid graft super absorbent polymer is studied.Effect of the pasted method of starch slurry,starch slurry concentration,the ammount of monomer,initiator,crosslinking agent,neutralization degree of monomer,reaction temperature and time. The optimum reaction condition as the deionized water absorption rate was gotten through single factors and five dimension quadratic regression orthogonal rotation experiment: starch slurry concentration 12.2 %,amount of initiator 2.7 mL, crosslinking agent 0.6 mL, monome 18.3 mL, neutralization degree of monomer 76.8 %,the distilled water absorption of SAP could reach 698 g/g.Secondly,performance analysis of the corn starch-acrylic acid graft super absorbent polymer is studied by electron microscope,scan electron microscope,infrared spectroscopy and X-ray diffraction.The result shows that:starch granules can not see in the surface of polymer,and have no effcets in water absorption.the major factor to the water absorption is the network structure formed through cross-linking.then,other properties,such as water absorption speed,water-holding capacity, performance reutilization,water-retention and reabsorption of the soil and biodegradability were studied.The result showed that:water absorption and water-holding capacity under high temperature and pressure were both superior.The water absorption of SAP is affected by the density of Na+ and Ca2+ in the solution,its reduced with the Na+ and Ca2+ concentration higher,absorption rate of artificial blood and artificial urine is lower,the SAP can improve the expansion,water retenation and reduce the evaporation of the soil,part of SAP can degradation in the incubator and inouclation with the soil extract.Comparatively,inouclation with the soil extract is better than incubator,Finally,plant the Chinese cabbage with the SAP,a control and five levels in the experiment.The results showed that:The SAP can improve the germination rate of the Chinese cabbage,the germination rate is 83.9 % when the SAP add volume at 0.4 %,its higher 29.4 points than control.Chlorophyll content was 31.4 when the SAP add amount at 3.2 %,4.98 times to the control,more nutrients was reserves for the plant.At the same time,with the increase in the amount of SAP ,the amount of MDA is increase in each level.There is no marked change when the add amount at 0.1 %,the content decreased when the add amount in 0.2 %～3.2 %.the minimum of the MDA is at the add amount of SAP is 3.2 %,has the best result.All about showed that:Use the SAP in Chinese cabbage plant can effectively improve the capability of drought-resistant.