Improved homopolymer separation to enable the application of 1H NMR and HPLC for the determination of the reaction parameters of the graft copolymerization of acrylic acid onto starch.

Graft copolymers of starch with acrylic acid are a promising green, bio based material with many potential applications. The grafting of acrylic acid onto cassava starch in an aqueous medium initiated by Fenton's reagent has been studied. Common grafting result parameters are add-on (yield) and graft efficiency (selectivity).

Insights in starch acetylation in sub- and supercritical CO2.

An in-depth study on the acetylation of starch with acetic anhydride (Ac(2)O) and sodium acetate (NaOAc) as the catalyst in pressurized carbon dioxide (scCO(2)) in a broad pressure range (8-25MPa) and a temperature of 90°C is provided. Highest degrees of substitution (DS) of 0.29 (1h reaction time) and 0.

The influence of viscosity on the functioning of molecular motors.

Light driven molecular motors based on sterically overcrowded alkenes achieve repetitive unidirectional rotation through a sequential series of photochemical and thermal steps. The influence of highly viscous environments on the functioning of unidirectional light driven molecular motors is established in the present report using three distinct media. Liquefied propane, a reference medium due to its low viscosity even at 85 K, and two binary solvent systems that undergo a well-defined glass-transition are used to evaluate the influence of glass-like viscosities on both photochemical equilibria and on thermal helix inversion in the molecular motors.