Starch polymer complexes

Rendleman, J. A. (2003). The reaction of starch with iodine vapor. Determination of iodide-ion content of starch-iodine complexes. Carbohydr. Polym. 51,191-202. 

Figure 16-6 (a) Schematic structure of the starch-iodine complex. The amylose chain forms a helix around l6 units. [Adapted from A T. Calabrese and A. Khan, "Amylose-lodine Complex Formation with Kl Evidence for Absence of Iodide Ions Within the Complex." J. Polymer Sci. 1999, A37,2711.] (fc>) View down the starch helix. Showing iodine inside the helix.8 [Figure kindly provided by R. D. Hancock, [rower Engineering, Sett Lake City.]... 

The most relevant achievements in this sector are related to thermoplastic starch polymers resulting from the processing of native starch by chemical, thermal and mechanical means, and to its complexation to other co-polymers. The resulting materials show properties ranging from the flexibility of polyethylene to the rigidity of polystyrene, and can be soluble or insoluble in water as well as insensitive to humidity. Such properties explain the leading position of starch-based materials in the biodegradable polymer field. 

Fig. 25.—The shift of the maximum of the specific rotation of the starch-iodine complex as the function of the concentration (c) of iodine (in I2-C6H10O5, mol/mol). (Reprinted with permission from R. C. Schulz, R. Wolf, and H. Mayerhoefer, Kolloid-Z., Z. Polym., 227 (1968) 65-72.)...

Starch. A complex polymer of glucose, used by plants and green algae to store surplus sugar for later use. 

Chapter 5 summarizes the investigation of lignocellulosic flax fiber-based reinforcement requirements to obtain structural and complex shape polymer composites. This chapter discusses in detail the possibility of forming complex shape structural composites which are highly desirable for advanced applications. Chapter 7 focuses on the structure and properties of cellulose-based starch polymer composites, while Chapter 8 focuses on the spectroscopic analysis of rice husk and wheat gluten husk-based polymer composites using computational chemistry. Chapter 9 summarizes the processing, characterization and properties of oil palm fiber-reinforced polymer composites. In this chapter, the use of oil palm as reinforcement in different polymer matrices such as natural rubber, polypropylene, polyurethane, polyvinyl chloride, polyester, phenol formaldehyde, polystyrene, epoxy and LLDPE is discussed. Chapter 10 also focuses on... 

Xrimnell, D., Shasha, B.S., Wing, R.E. and Otey, F.H. (1982) Pesticide encapsulation using starch-borate complex as wall material. Journal of Applied Polymer Science, 27, 3919-3928. 

Amylose is a linear a-D-(l—s-4)-glucan (4-136), and, therefore, is actually a polymer of the disaccharide maltose. To a limited extent, branching occurs at about ten sites of the molecule. Amylose is partially esterified with phosphoric acid (wheat starch contains 0.055% and potato starch 0.07-0.09% of phosphorus) and in cereal starches forms complexes with lipids. An amylose molecule has one reducing monosaccharide residue. 

The starch-iodine complex does not have a well-defined stoichiometry. The ratio [I ]/([l2]+[IJ]) must be greater than zero in aqueous solution. The actual stoichiometry depends on the polymer chain length, the iodide and salt... 

Although starch polymers from different natural sources have the same elemental composition, starch polymers are composed of linear amylose and branched amylopectin molecules. The ratios of linear and branched molecules in starch polymers are dependent on the source of starch. Proteins and biopolymers are more complex and variable in composition and structure than cellulose and starch polymers. The properties of proteins and biopolymers are dependent on their natural sources. ... 

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