Maize starch blends

NR/maize starch blends exhibit poor mechanical properties due to the characteristics of the starch and the low interfacial interactions between the two phases. The 1 part per hundred of rubber (phr) of glycidyl methacrylate was an appropriate compatibilizer to improve the compatibility and mechanical properties compared to the uncompatibilized blends because the epoxy group of the glycidyl methacrylate chemically interacted with the hydroxyl group of the maize starch and greatly decreased the cohesion energy and the erystal-lization of the starch. Therefore, starch molecules become better dispersed in the NR matrix and increase the interfacial interaction between the hydrophilie starch and the hydrophobic NR. ... 

Mohammed, Z. H., Hember, M. W. N., Richardson, R. K., and Morris, E. R. 1998. Application of polymer blending laws to composite gels of agarose and crosslinked waxy maize starch. Carbokydr. Polym. 36 27-36. 

Large amounts of adhesive mixtures, mainly based on potato or com (maize) starch (with plant varieties grown specifically for the purpose), are employed in paper coating, where the adhesive provides a bond between the fibrous (wood-pulp based) stmcture of the paper and the white china-clay-based surface layer, which can be printed. To improve performance in printing processes, these surface layers are often blended with wood rosin-based products and with polyvinyl alcohol of synthetic origin. Polyvinyl alcohol in adhesives (and its precursor polyvinyl acetate) can be made from ethanol obtained by the fermentation of starch - and once were so made - but the processes, carried out in dilute aqueous solution, are immensely wasteful of thermal energy. 

M. M.H. Senna, Y.K.A. Moneam, A.A.A. Hakiem, H.M. Said, Characterization of plasticized maize starch/chitosan blends irradiated with an electron beam. Journal of Polymer... 

The naturally biodegradable polymers such as starch, chitosan and cellulose derived from natural sources have produced a number of interesting NR blends and IPNs. These blended systems have an advantage in that they create fewer waste disposal problems compared to the petroleum based polymeric materials. The use of stareh blends to enhance the biodegradability of conventional plastics has been reported by many researchers in order to reduce the environmental impaet of petroleum based plastic products and waste. The NR/maize stareh blends exhibited a decrease in their mechanical strength due to the speeifie properties of starch. However, the blended polymers showed a low interfaeial interaetion between the two phases due to the different polarity behaviour of the hydrophobic NR and the hydrophilic starch. 

COMPOSAC 14 1, made from Mater-Bi Z, i.e., a blend of maize starch, PCL and additives. 

Blaszczak W, Fornal J, Kiseleva VI, Yuryev VP, Sergeev AI, Sadowska J. 2007. Effect of high pressure on thermal, structural and osmotic properties of waxy maize and Hylon VII starch blends. Carbohydr Polym 68 387-396. 

Investigations into the viscoelastic properties of TPS were performed by Mitrus [35] for granulate from blends of potato, wheat, and maize starch with 20% and 25% glycerol contents. In the case of granulates from potato starch the impact of extrusion ratio on the changes in viscoelastic properties was studied. 

Surimi is fish paste from deboned fish used to make simulated crab legs and other seafood. For preservation the paste is blended with cryoprotectants, such as sucrose, sorbitol and phosphates, and frozen. To make the final product, the frozen paste is thawed, blended with starch and extruded as a film onto a belt. The belt takes the film into an oven that heat-denatures the fish protein and cooks the starch. The film is then rolled to form striations, shaped, colored and cut. Depending on the required distribution, the product is frozen or refrigerated. Potato and tapioca starch were used in surimi products 400 years ago, since they provided a cohesive, elastic matrix consistent with seafood. Frozen distribution has made the use of highly-stabilized, moderately crosslinked tapioca starch popular, alone or with native tapioca starch. Modified waxy maize products are used, as is unmodified com starch, for increased cuttability. Kim188 reported that the gel strengthening ability of starch correlates with starch paste viscosity. 

Starch PoIy(ethyIene-vinylalcohol) copolymer, 56% VA waxy maize, native com and high-amylose starches extrusion-blended x-ray, DSC, SEM, TEM Phase separated starch domains. Oriented droplets, 0.05-5 jm in length (waxy maize), 0.05-1.2 pm domains (native com), <0.25 pm (high amylose) (81)... 

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