| Super absorbent resin is a new kind of functional polymer material, which has been found extensive application in many fields such as hygienic products, agriculture and soil conditioning for its particular absorbency and retention characteristics. Acrylic acid (AA)-based super absorbent resin has a broad raw material source and simple synthetical technics, generally exhibits very high absorbency in deionized water. However, the application performance was influenced seriously because of its poor resistance to salts and humidity. Consequently, the research on improving salt-resisting property of resins has been widely focused on. The properties of Super absorbent resin was influenced greatly by climates and environments during the applied course. The resin need to attend saturation in short time usually. Therefore, the water absorbing rate needs to be improved.The preparation method of AA based super absorbent resin was improved in this paper. According to free radical grafted polymerization theory, starch and partly neutralized acrylic acid were copolymerized to prepare super absorbent resin. The factors that affluent the water absorbency and salt water absorbency were investigated, including the proportion of starch to acrylic acid, monomer amount, initiator amount, crosslinker amount etc, via mono factor method systematically. The best reaction conditions were obtained: Starch gelatinization temperature is 60～65℃, gelatinization time is 0.5h, the prophase temperature of grafted polymerization is 55～60℃, the anaphase temperature of grafted polymerization 60～65℃and the polymerization time is 2.5～3.0h.Poly-vinyl alcohol had better salt resistance and gel intensity compared to pure AA-based super absorbent resin for the presence of hydrophilic hydroxyl. It can satisfy more broad application requirements. In order to improve products' performance such as salt-resistance, water retention and water absorbing rate, PVA segment was introduced into water absorbing resin to get better water absorbency, salt resistance and gel intension super absorbent resin. The influence of many reaction conditions on the resin were discussed. IR and X-ray analysis showed that starch and acrylic acid have grafted together. In addition, silane coupling agent could be hydrolyzed into crosslinked network when meet water. Silane coupling agent was introduced into the polymerization system of water absorbent resin to conduct the interpenetrating process. TG analysis showed that, as the increase of the crosslink modified agent, resin's thermal stability improved, the thermal stability of PVA resin was better than SA resin.Pore-forming technology was introduced into the synthesis of AA-based super absorbent resin. Fast-swelling porous super absorbent resins were prepared by grafting acrylic acid onto corn starch through free-radical polymerization in aqueous solution using sodium dodecyl sulfate, sodium dodecyl sulfonate and p-octyl poly(ethylene glycol)phenyl ether as pore-forming agents. The influence of reaction conditions on resin's water absorbing performance was discussed. SEM analysis showed that the surface of the non-modified resin was smooth and dense, didn't have pore structure. The surface of modified resin was more rough and porous. This structure had relatively big specific surface area, water molecular was much easier to get into the inner of the resin and combine with hydrophilic group. Water absorbing rate was 4～5 times faster than non-modified resin.Second dehydrate method was used to deal with the composed super absorbent resin for the first time. The products' water absorbing rate improved greatly while the water absorbency changed little. The solvent used in this course can be reused to save cost. SEM analysis showed that pore-forming structure was formed, water absorbing rate was 5～6 times faster than the non-modified resin.
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