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gamma-polyglutamic acid (gamma-PGA) water-absorbent resin is a biodegradable novel functional polymer materials, the structure by to moderately crosslinked three-dimensional network, which can absorb hundreds of times of its own weight even times the dry water . Broad application prospects in the field of agriculture, forestry, horticulture, medicine and health, environmental protection and light food. This thesis is to start from the cross-linking reaction of linear poly-glutamic acid gamma-PGA absorbent resin as a crosslinking agent, using a range of different molecular weight polyethylene glycol glycidyl ether, its manufacturing process and properties have been studied and gamma-PGA absorbent resin was modified, made a preliminary study of its agricultural applications. First, diethylene glycol diglycidyl ether and polyethylene glycol diglycidyl ether preparation process. Dipropylene glycol and epichlorohydrin as a raw material, a boron trifluoride diethyl ether complex as the catalyst synthesis of low viscosity diethylene glycol ether, and its preparation process are discussed, at the same time, using a Fourier transform infrared spectroscopy and epoxy value of its analysis shows that the expected results are consistent. When diethylene glycol amount to 0.05 mol, the amount of the boron trifluoride ether complex 3ml, epichlorohydrin and diethylene glycol molar ratio of 4:1, sodium hydroxide, and The diethylene glycol molar ratio of 2:1, at about 40 ℃ cyclization, a low viscosity, yield 81% of the product. Synthesis of polyethylene glycol ether, wherein the ratio of polyethylene glycol with epichlorohydrin, KOH dosage, the amount of catalyst, reaction temperature and the like factors. Obtained by orthogonal experiments the optimum reaction conditions, when taken 0.05mol polyethylene glycol, a reaction temperature of 55 ° C, polyethylene glycol with epichlorohydrin molar ratio as 1:6, KOH dosage for 5.8G catalyst tetrabutyl bromide used in an amount of 0.8g, polyethylene glycol diglycidyl ether epoxy value of the reaction 8h obtained under this condition close to the theoretical epoxy value, a yield of 62.5%, and were characterized by IR and an epoxy value, with the expected results. Secondly, gamma-poly glutamic acid as raw materials, were made of different molecular weight polyethylene glycol ether as the crosslinking agent, and ultimately the preparation process of the gamma-PGA absorbent resin. Including gamma-PGA concentration, the amount of crosslinking agent, the reaction pH value, reaction time, reaction temperature, etc. influence on the water absorption rate and the yield of the product. The results showed that: PEG-1000-epoxide with polyglutamic acid synthesis resin through a series of experiments, the water absorption of 2200g / g for highest. The concentration of gamma-PGA's is 18%, the amount of crosslinking agent is poly-glutamic acid monomer molar amount of 8%, pH4.8, 60 ° C under a reaction to 40h, the superabsorbent can be prepared by a coefficient of water absorption of 2200g / g
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