Those who know it, please share the reaction mechanism of alkali treatment of starch
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This post was last edited by sheyfox on 2011-5-3 at 10:17 :handshake First, thanks to those who helped. Regarding the mechanism of the adhesive, or the reaction mechanism in the process of alkali treatment of starch
Reply 1# sheyfox: The monomer of starch has two hydroxyl groups, making it equivalent to a diol. When a diol reacts with a base, it behaves like a weak acid reacting with a strong base, resulting in the formation of a sodium alcohol
Reply to 2# Starless Nebula: What is the bonding mechanism of caustic starch, and what is its relationship with this sodium alcohol?
Starch is hydrolyzed in the presence of alkali to produce starches or polysaccharides with lower molecular weights; the final product of this hydrolysis is glucose. The cohesion of starch is due to hydrogen bonds between its polyhydroxyl groups
The causticization of starch is primarily a hydrolysis process; it is impossible to produce sodium alcohols in the presence of water, as sodium alcohols cannot exist under such conditions. The person who wrote this didn’t study organic chemistry properly. Starch bonding is due to multiple hydrogen bonds; there are not many chemical bonds involved, and it is primarily physical bonding. In the presence of water, hydrogen bonds can form with water, which reduces the bonding strength – this is why starch adhesives are not resistant to water.