Search results for "Cellulose derivatives"
showing 5 items of 5 documents
Influence of shear rate and concentration ratio on viscous synergism. Application to xanthan—Iocust bean gum— NaCMC mixtures Influencia de la velocid…
2000
A method is described that allows the development of an empirical approach to quantify synergistic interactions and their variations with shear rate. The approach is based on the definition of a viscous synergism index, Iv. The method is applied to xanthan-locust bean gum gels, and an equation is developed for relating the synergism index to shear rate, γ, and the locust bean gum/xanthan gum concentration ratio, z. The value of at which that function has a maximum, IMV, is calculated. This value of z provided an estimation of the proportion of gums at which maximum synergism occurs. A decreasing exponential dependence of these IMV on γ is shown. The influence of the addition of a fixed pro…
Solid opalescent films originating from urethanes of cellulose
1997
Die molekularen Konstanten von Polycarbonaten in Lösung
1959
An einer Reihe von fraktionierten Polycarbonaten werden in zwei Losungsmitteln die Diffusions- und Sedimentationskonstanten, die Viskositatszahlen, die osmotischen Drucke sowic die Lichtstreuung gemessen. Daraus wird eine Eichkurve zur viskosimetrischen Molekulargewichtsbestimmung abgeleitet und aus einem Vergleich der verschidednen Mittelwerte des Molekulargewichts die Uneinheitlichkeit der Fraktionen abgeschatzt. Aus den Reibungs-und Lichtstreuungsdaten werden die Knauelabmessungen berchnot und mit Hilfe der gemessenen zweiten Virialkoeffizientin auf das indifferente Losunmittal reduziert. Die Volumbeanspruchung der Polycarbonatmolekule in Losung ist groser als die vergleichbarer Polyviny…
Preparation of cholesteric particles from cellulose derivatives in a microfluidic setup
2011
A microfluidic setup was used to process lyotropic cholesteric liquid crystalline mixtures of cellulose derivatives into spherical particles in the micrometre scale. By the method of co-flowing injection, monodisperse droplets of the liquid crystal, dispersed in an aqueous carrier fluid, were prepared. Polymerization of the acrylic solvent with UV-light fixed the orientation obtained by the flowing motion. The resulting particles were characterized by polarizing optical microscopy.