ARS | Publication request: Complexation and Blending of Starch, Poly(acrylic Acid), and Poly(n-Vinyl Pyrrolidone)

Submitted to: Carbohydrate Polymers
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: January 18, 2006
Publication Date: N/A

Interpretive Summary: Starch is a well-known, versatile, and inexpensive agricultural material used for a variety of industrial applications. In addition to being a major food item, it is currently used industrially as coatings and sizing in paper, textiles and carpets, as binders and adhesives, as absorbants, and as encapsulants. Often it is modified to improve its end-use properties, e.g., oxidation, hydrolysis, and substitution with an ether, an ester or a quaternary amine. In our desire to seek further applications that will add value to starch, we look at novel blends of starch with other commercial polymers. In this work, we sought to improve the properties of starch through non-covalent means, viz., the blending of starch with poly(acrylic acid), poly(N-vinyl pyrrolidone), and poly(N-vinyl pyrrolidone)-iodine. An emphasis was placed on the rheological and gel forming properties. Starch was found to form a synergistic mixture with poly(acrylic acid). It has no effect on poly(vinyl pyrrolidone) but produces a gel with poly(vinyl pyrrolidone)-iodine. The addition of a small amount of a third polymer caused either increased viscosity (at low addition levels) or gel formation (at higher levels). These observations are rationalized on the basis of specific interactions among the polymers. Several specific compositions of these blends may find applications as thickeners and encapsulation agents.

Technical Abstract: Starch is often modified to improve its end-use properties. In this work, we sought to improve the properties of starch through non-covalent means, viz., the blending of starch with poly(acrylic acid), poly(N-vinyl pyrrolidone), and poly(N-vinyl pyrrolidone)-iodine. An emphasis was placed on the rheological and gel forming properties. Starch was found to form a synergistic mixture with poly(acrylic acid). It has no effect on poly(vinyl pyrrolidone) but produces a gel with poly(vinyl pyrrolidone)-iodine. The addition of a small amount of a third polymer caused either increased viscosity (at low addition levels) or gel formation (at higher levels). These observations are rationalized on the basis of specific interactions among the polymers. Several specific compositions of these blends may find applications as thickeners and encapsulating agents.