| Starch is high molecular compound that be linking with a-1,4and a-1,6glucose by a-D-glucose, starch molecules contains a lot of hydroxyl groups. So reactive hydroxyl can be made into a variety of starch derivatives, Starch can made into multifunctional compound by cross linking reaction, and starch also can be grafted with a variety of monomers grafted copolymer.The super absorbent polymer (SAP) was developed in the1960s, it is functional polymer-electrolyte materials that contain strong hydrophilic group, three-dimensional structure. In recent years starch grafted super absorbent polymer is a hot topic of research that can reduce environmental pollution. From the point of view improving the polymerization conditions and grafting yield. The important is screening absorbent resin with high amount of starch that is high water absorption, high graft ratio, good reproducibility and polymerization conditions are mild and inexpensive non-toxic. So far, although the production conditions of the starch graft copolymer has basically taken shape, the product of absorption and water retention is also very excellent. But from the point of view of industrial production and practical application, there are still many problems. First, the production process is complex, monomer content is high that not only increase production costs and pollute environment and the polymer is not easily degradable. To these problems, SAP was synthesized with acrylic of industrial grade as monomer, ammonoum persulfate(APS) as initiator, cheap natural starch as polymeric main chain, that was high water absorption, high gel strength and high grafting efficiency. It also can study of adhesive for labeling bottle.Starch is non-toxic low-cost natural polymer materials that is not only used as the water absorbent resin, but also can product adhesive of starch grafted acrylic ester monomers with the method of emulsion polymerization.The article is preparation of super absorbent polymer by graft copolymerization of acrylic acid onto starch by intermittent method. The structure of copolymers was characterized by IR and XRD analysis. On the basis of oxidized starch, the influence of different reaction conditions on bibulous rate and the salt water rate, such as the reaction temperature、reaction time、gelatinous time、initiator dosage and the degree of neutralization are discussed and examine the influence of the amount of cross linking agent on starch grafted efficiency. Intermittent method was prepared starch grafted acrylic emulsion, the influence of oxidation temperature of starch、gelatinization time, oxidation time, emulsifier, oxidant dosage, starch dosage and rigid-flex monomer ratio on the emulsion polymerization process and the properties of latex film are researched.The results indicate when the reaction temperature is75℃, reaction time is4h, the starch’s gelatinous time is40min, dosage of initiator accounted for0.6%of the monomer, the degree of neutralization is80%, the bibulous rate of resin is the highest, salt water absorption rate is best. When the cross linking agent accounted for0.8%of the monomer, m(starch): m(AA) is1:3, then the bibulous rate of resin is the highest. The structure of wetting polymers is pine needle. It can achieve resin of every gram weight500times more. When the cross linking agent accounted for1.0%of the monomer, this time grafting efficiency may reach98.28%. The result of starch grafted acrylic ester monomers with the method of emulsion polymerization is when the oxidation temperature is85℃，the oxidation time of60min, the reaction time3h, oxidants accounts for monomer3%, proportion of starch and monomer0.75and proportion of soft and hard monomers1:2, then the monomer conversion rate is highest, and the emulsion has good appearance and low water absorption of coating. Film has a good adhesion if using borax as crossing linker. |
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