Starch, modified oxidation

Starch oxidation was investigated as early as 1829 by Liebig. The objective, as with other modifications, was to obtain a modified granular starch. The oxidant commonly employed is sodium hypochlorite, prepared from chlorine and aqueous sodium hydroxide. This reaction is exothermic and external cooling must be provided during preparation of the oxidant. 

Modified starches may be acid-modified, oxidized, or heat-treated. Acid-modified (thin-boiling) starches are used mainly in textiles as warp sizes and fabric finishes. Here they increase yam strength and abrasion resistance and improve weaving efficiency. Tbin-boiHng starches also have selected appHcations in paper and laundry starch preparations. 

Lactose monohydrate, corn starch, modified starch, povidone 25000, magnesium stearate, HPMC, Macrogol 6000, talc, titanium dioxide, ferric oxide pigment, yellow NF... 

Function Bleaching, oxidizing agent starch modifier antimicrobial agent. 

L Jamstrdm, L Lason, M Rigdahl, U Erikson. Flocculation in kaolin suspensions induced by modified starches 2. Oxidized and hydrophobically modified oxidized starch in comparison with poly(vinyl alcohol) and carboxymethyl-cellulose. Coll Surf A 104 207-216, 1995. 

Synonyms Bleached starch Classification Food starch modified Definition Starch which has been treated with low levels of oxidant to improve whiteness without affecting other key props, such as vise. 

Texsolve V. See VM P naphtha Textaid -A. See Food starch, modified Textamine 0-1, Textamine 0-5. See Oleyl hydroxyethyl imidazoline Textamine Oxide LMW. See Lauramine oxide Textamine T-1. See Tall oil hydroxyethyl imidazoline... 

Ethylene/vinyl acetate/vinyl alcohol copolymer Ethyl methacrylate Ferric oxide Fluorinated ethylene/propylene Food starch, modified Glyceryl triacetyl hydroxystearate Hexyl alcohol Hydrogenated styrene/2-methyl-1,3-butadiene block polymer Hydrogenated tallow lonomer resin... 

CF 32,5007 Coarse 65996-62-5 Food starch, modified Pure-Bind B910 Pure-Bind B923 Starch, oxidized... 

Chemical or enz5miatic agents may also be used to destructur-ize, oxidize, or derivatize the starch. Modified starches have been used to make biodegradable plastics, wherein the modified starch is blended as an additive or the minor component with petroleum-based or synthetic pol5m ers. 

Chem. Descrip. Starch modified by oxidation (maize, wheat) or esterification (high amylose)... 

INS1404 E1404 Synonyms Oxidized starch Classification Food starch modified... 

O. are - modified starches by oxidation of granular native or degraded starches, leading to formation of some aldehydic and/or carboxylic groups at the sites of primary or secondary hydroxylic groups. 

The properties of the starch depend on how it is treated or modified. The best results are achieved by ethylation. However, the most economical method of modification is enzymatic degradation to prepare enzyme-converted starches. Also, oxidized starches are widely used in North America. Table 4-5 compares the advantages and disadvantages of using starch as a binder. 

Pyrotechnic mixtures may also contain additional components that are added to modify the bum rate, enhance the pyrotechnic effect, or serve as a binder to maintain the homogeneity of the blended mixture and provide mechanical strength when the composition is pressed or consoHdated into a tube or other container. These additional components may also function as oxidizers or fuels in the composition, and it can be anticipated that the heat output, bum rate, and ignition sensitivity may all be affected by the addition of another component to a pyrotechnic composition. An example of an additional component is the use of a catalyst, such as iron oxide, to enhance the decomposition rate of ammonium perchlorate. Diatomaceous earth or coarse sawdust may be used to slow up the bum rate of a composition, or magnesium carbonate (an acid neutralizer) may be added to help stabilize mixtures that contain an acid-sensitive component such as potassium chlorate. Binders include such materials as dextrin (partially hydrolyzed starch), various gums, and assorted polymers such as poly(vinyl alcohol), epoxies, and polyesters. Polybutadiene mbber binders are widely used as fuels and binders in the soHd propellant industry. The production of colored flames is enhanced by the presence of chlorine atoms in the pyrotechnic flame, so chlorine donors such as poly(vinyl chloride) or chlorinated mbber are often added to color-producing compositions, where they also serve as fuels. 

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