Submitted to: Carbohydrate Polymers
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/21/2010
Publication Date: 5/23/2010
Citation: Shogren, R.L., Biswas, A. 2010. Acetylation of Starch with Vinyl Acetate in Imidazolium Ionic Liquids and Characterization of Acetate Distribution. Carbohydrate Polymers. 81(1): 149-151. Interpretive Summary: This research found that modified corn starch with controlled substitution patterns could be made in a simple manner and that these have potential use in coatings, adsorbents and thickeners. Corn starches with new properties and applications could be created if techniques were developed to control where on the starch molecule that the chemical modification occurs. It has been shown that starches with acetate substitution predominantly at the 2 position and randomized at 2, 3 and 6 positions can be made using different ionic liquids as solvents. These ionic liquids have no vapor pressure (fumes) and can be easily recycled so they are environmentally friendly. This information will benefit scientists in academia and industries who are involved in making water soluble polymers for applications such as water soluble coatings, adhesives, plasma expanders, etc.
Technical Abstract: Starch was acetylated with vinyl acetate in different 1-butyl-3-methylimidazolium (BMIM) salts as solvent in effort to produce starches with different acetylation patterns. Overall degree of substitution was much higher for basic anions such as acetate and dicyanimide (dca) than for neutral anions such as chloride and nitrate. There was a strong preference for acetylation at the C2 position in BMIM dca while acetylation was similar for C2, C3 and C6 in BMIM OAc. Molecular weights were not changed significantly by the reaction conditions. These results suggest that ionic liquids can provide a convenient medium for the homogeneous modification of starches with some control over substitution patterns.