| Activated clay has many advantages, such as large specific surface, strong adsorption and decolorizing ability, high activity. It can be widely used in oil decoloring, absorbent, catalyst, etc. however, the development of activated clay is very late in our country, and the deep processing products are very less as well, Therefor, it is necessary to strengthen the processing product exploration of activated clay for the long-term development. Alkaline clay is the new kind of bentonite which possesses anion exchange property and has been developed in recent years. It was prepared by calcium hydroxide and activated clay whose surface is covered with acid active sites. Compared with the alkaline Ca-bentonite, the alkaline clay adopts by the wet process, which makes its production process more simply, the production period shorter, the product yield higher and cost lower. The loading layer numbers of alkaline clay can be controllable so that it can be applied to many application flieds which need different alkali capacity. Since alkaline clay’s surface is filled with hydroxyl, which can be react with many organic acid to prepare organobentonite. Gluconic acid is a polyhydroxy organic acid and can be used to modify alkaline clay to get a new type of organobentonite which has good hydrophilicity and good compatibility with polyhydroxy polymer.Because alkaline clay which loaded with more calcium hydroxide layers has poor stability, the monolayer of alkaline clay, whoes loading amount is1.77mmol·g-1was used to react with gluconic acid to prepare gluconic clay in this paper. Through exploring the preparation and mechanism of gluconic clay, the optimum conditions of gluconic clay were obtained. Acid-base neutralization reaction occurred between gluconic acid and calcium hydroxide, which was in and on the alkaline clay layer. The bentonite layers were exfoliate due to the intense heat released from reaction. The gluconic clay keeps the layered structure of montmorillonite, and the numbers of hydroxyl are increased evidently. Meanwhiles, gluconic clay improves the diapersity in the natural polymers or synthetic hydrophilic polymers.Gluconic clay was applied in the modification of starch/poly(vinyl alcohol) in this paper, And a single factor analysis was used to prepare a new type of high performance complex material of starch/PVA/gluconic clay. In addition, the complex material was characterized by means of FT-IRD, XRD and SEM. And the best process, for the complex material was given by experiment:mass ratio of starch and PVA was6:4, plasticizer glycerol and formaldehyde was1.5%and2%of the total system mass, respectively, gluconic clay was2%of the starch and PVA total mass. Furthermore, analysis showed that the mechanical properties, water resistance and transmittance of complex films were improved with different degree.The results above provide the reference for the study of degradable plastics. Finally, the mechanism study revealed that the gluconic clay disperse in the mixture of colloidal solution evenly, and associate with starch and PVA molecular with hydrogen bond. The three molecular got into each other as a mesh by cross-linking, so the performance of film was improved. |
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