Carbamoyl starches

Starch and urea were combined under pressure in order to produce an adhesive for corrugated paperboard2616 and a thickener for frozen food.2660 Carbamoylated starch could also be further reacted with formaldehyde and amines2661 or with... 

Modification of carbamoylated and carbaminated starches by oxidation and crosslinking with formaldehyde was reported.2623 Crosslinking was used to produce fire-resistant construction boards.1360 A size for cellulose fabrics was produced by crosslinking poly(carbamoylethyl)ethers of starch with formaldehyde.1351... 

The determination of the carbamoyl group in starch carbamates is based on cleavage of the carboxyamido group from the carbamate in alkaline hydrolysis. For this determination, the ammonia liberated is steam-distilled into boric acid followed by titration with 0.05 M aqueous sulfuric acid.2665 Additional information on starch carbamates can be found in the article by Roberts.2666... 

As an answer to the growing demand for products made from renewable resources and with (modified) starch as a reference in mind, a lot of these starches have been devoted to the chemical modification of inulin [3]. Hydrophobization of inulin, e.g. grafting of alkyl chains on to the inulin backbone and as such obtaining an inulin derivative showing the wanted amphiphilic character, can be done in several ways by esterification, by etherification or by carbamoylation. The reactions are usually performed in solvents like pyridine, dimethylformamide or dimethylsulfoxide, using catalysts like, for example, sodium acetate, potassium carbonate or triethylamine. 

---