Starch derivatives alkaline degradation

Starch derivatives may also undergo hydrolysis and degradation under alkaline conditions. The hydrolysis of the nitriles, amides, and esters resulting from the reaction of starch with corresponding vinyl monomers is obvious. Considerable attention has been paid to the alkaline degradation of starch dialdehyde. It de-polymerized readily supposedly as a result of -elimination at C-5, although such a questionable -elimination should not be facile).70... 

Desizing by chemical decomposition is applicable to starch-based sizes. Since starch and its hydrophilic derivatives are soluble in water, it might be assumed that a simple alkaline rinse with surfactant would be sufficient to effect removal from the fibre. As is also the case with some other size polymers, however, once the starch solution has dried to a film on the fibre surface it is much more difficult to effect rehydration and dissolution. Thus controlled chemical degradation is required to disintegrate and solubilise the size film without damaging the cellulosic fibre. Enzymatic, oxidative and hydrolytic degradation methods can be used. 

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