Grafting of oligosaccharides onto synthetic polymer colloids.

A new method to form colloidally stable oligosaccharide-grafted synthetic polymer particles has been developed. The oligosaccharides, of weight-average degree of polymerization approximately 38, were obtained by enzymatic debranching of amylopectin. Through the use of a cerium(IV)-based redox initiation process, oligosaccharide chains are grafted onto a synthetic polymer colloid comprising electrostatically stabilized poly(methyl methacrylate) or polystyrene latex particles swollen with methyl methacrylate monomer.

Synthesis of anisotropic nanoparticles by seeded emulsion polymerization.

Anisotropic polystyrene nanoparticles of diameters below 0.5 microm were prepared by coating the surface of cross-linked polystyrene latex particles with a thin hydrophilic polymer layer prior to swelling the particles with styrene and then initiating second-stage free-radical polymerization. Conditions were found so that all particles had uniform asymmetry.

Improved methods for the structural analysis of the amylose-rich fraction from rice flour.

Cooking and sensory properties of rice are largely determined by the amylose content and structure. For relationships between functional and structural properties, a more accurate method to determine the structure of amylose is required. Here we calibrate size exclusion chromatography (SEC) columns, using Mark-Houwink parameters for linear starch and pullulan standards, to obtain the true molecular weight distribution of linear starch.