Starch acetate blends

Ganjyal, G. M., Reddy, N., Yang, Y. Q., and Hanna, M. A. J. (2004). Biodegradable packaging foams of starch acetate blended with corn stalk fibers. 

Starch acetates are one of the more common derivatives of starch and are made from starches with a variety of different amylose to amylopectin ratios. The reaction differs from other substituted starches in that it is begun with a neutral water starch slimy (pH 7 to 8), which is then blended with acetic anhydride [Figure 14] (34), acetic acid (35), vinyl acetate (36), or a number of other acetyl donating reagents (37,38,39). 

Meyer, J.M. and Elion, G.R. (1994) Starch cellulose acetate blends. US Patent S288S18 to USiVrmy, Natick Lab.). 

So far, various bio-based polymers have been developed, e.g., cellulose acetate, poly(alkylene succinate)s, starch-based blends, poly(3-hydroxy alkanoate)s (PHA) [1], poly(lactic acid) (PLA) [2], etc. Nowadays, some typical commodity plastics have also been S5mthesized from biomass, for example, polyethylene, polypropylene, poly(methyl methacrylate) [3], polyamide-4 [4], and polycarbonate [5]. If plastic materials are synthesized from renewable resources and circularly utilized with precise control of their depolymerization, an ideal recycling system could be constructed for plastic products, in which the resources and production energy could be minimized. Thus, the development of bio-based recyclable polymers is significant. In Scheme 9.1, t5 ical... 

The main product group is - starch-based and is used for cotton and its blends with other fibers. Native, - pregelatinized starch, which has the disadvantage of - retrogradation, is increasingly substituted by starch derivatives, such as - starch phosphates or - starch acetates, as well as starch ethers, such as - hydroxyethyl starch... 

Maheras, J. C., John, J., Hopkins, B. Tatzlaff, H. (1995). Polymer blend composed of cellulose acetate and starch acetate and starch used to form fibers, films and plastic materials and a process to prepare said blend, U.S. Patent 5,446,140, Aug. 29. 

Other blends such as polyhydroxyalkanoates (PHA) with cellulose acetate (208), PHA with polycaprolactone (209), poly(lactic acid) with poly(ethylene glycol) (210), chitosan and cellulose (211), poly(lactic acid) with inorganic fillers (212), and PHA and aUphatic polyesters with inorganics (213) are receiving attention. The different blending compositions seem to be limited only by the number of polymers available and the compatibiUty of the components. The latter blends, with all natural or biodegradable components, appear to afford the best approach for future research as property balance and biodegradabihty is attempted. Starch and additives have been evaluated ia detail from the perspective of stmcture and compatibiUty with starch (214). 

Other uses of blends include controlled rate of fertilizer release(77) based on ethylene/vinyl acetate/carbon monoxide polymers which is U.V. sensitive, polyolefin blends with any biodegradable polymers,(78) and polyolefins blended with metals and autoxidizable substrates. (79) Doane and co-workers(80) at the U.S.D.A. have used grafted starches in many applications, including soil stabilization. 

Sealing tape has 35 to 90 pounds per ream of kraft paper as a substrate, whereas, reinforced sealing tape is based on a bonded laminate of kraft paper, reinforcing fibers, and kraft paper. The adhesives applied to these substrates may be thin-boiling, waxy starches alone, or blended with a soluble dextrin (5). More recently, blends of a soluble dextrin with oxidized potato or a hydrox-ypropyl ether of an oxidized potato starch are being used (9). Also, the acetate or succinate of an oxidized waxy starch may be used (15) as well as specially produced waxy starch acrylamide graft copolymer products (16). 

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