Sulfated starches

Sodium hydrogen sulfate, Starch, Sodium carbonate Anon., fnd Eng. Chem. (News Ed.), 1937, 15, 282... 

Until 1870, blackpowder was the only explosive used in coal mining, and several disastrous explosions occurred. Many attempts were made to modify blackpowder these included mixing blackpowder with cooling agents such as ammonium sulfate, starch, paraffin, etc., and placing a cylinder filled with water into the bore hole containing the blackpowder. None of these methods proved to be successful. 

Other applications of fluidization have been made to such materials as sodium chloride liable salt), soda ash. sodium phosphate, sodium sulfate, starch, talc, magnesium oxide, dry clay, bone acid, hydrated lime, and various high polymers in powdered or head" form. Fluidization is especially effective in loading and unloading materials from railroad cars and trucks, as well as in moving them aboul within the plant. 

Specific interactions between starch and proteins were observed as early as the beginning of the twentieth century. Berczeller996 noted that the surface tension of aqueous soap solutions did not decrease with the addition of protein (egg albumin) alone, but it did decrease when starch and protein were added. This effect was observed to increase with time. Sorption of albumin on starch is inhibited by bi- and trivalent ions and at the isoelectric point. Below the isoelectric point, bonding between starch and albumin is ionic in character, whereas nonionic interactions are expected above the isoelectric point.997 The Terayama hypothesis998 predicts the formation of protein complexes with starch, provided that starch exhibits the properties of a polyelectrolyte. Apart from chemically modified anionic starches (such as starch sulfate, starch phosphate, and various cross-linked starch derivatives bearing ionized functions), potato starch is the only variety that behaves as a polyelectrolyte. Its random phosphate ester moieties permit proteins to form complexes with it. Takeuchi et a/.999-1002 demonstrated such a possibility with various proteins and a 4% gel of potato starch. 

The bulk material may ignite or explode in storage. Traces of water may initiate the reaction. A rapid exothermic decomposition above 175°C releases oxygen and chlorine. Moderately explosive in its solid form when heated. Explosive reaction with acetic acid + potassium cyanide, amines, ammonium chloride, carbon or charcoal + heat, carbon tetrachloride + heat, N,N-dichloromethyl-amine + heat, ethanol, methanol, iron oxide, rust, 1-propanethiol, isobutanethiol, turpentine. Potentially explosive reaction with sodium hydrogen sulfate + starch + sodium carbonate. Reaction with acetylene or nitrogenous bases forms explosive products. 

Typical a. are - carboxymethyl starch (- starch ethers), starch adipate, starch citrate, starch mal-eate, starch phosphate, starch succinate, starch sulfate, starch xanthate (->starch esters), - oxidized starches. 

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