Separation of linear and star‐shaped polystyrenes by phase distribution chromatography

Abstract

The phase distribution chromatographic technique was optimized and applied for the separation of linear and star-shaped polystyrene (PS). For this purpose non-crosslinked, ultra high molecular weight PS coated on different supporting materials was used. The stability of the coating under chromatographic conditions was tested by thermo gravimetric analysis and microscopic techniques. The modification of different column packing materials was tested. Separation according to branching was indicated for different molecular weights of linear and star-shaped PS. The resolution of the separation was improved by changing the density of the stationary phase and the temperature. The separation results were supported by cloud point measurements and the determination of the critical conditions for linear and star-polymers at the same molecular weight.

Solution characterization of a hyperbranched polysaccharide carbamate derivative and specific phase separation behavior due to chain branching

“…9 This can be used for the separation of linear and branched polymers. 10 Phase separation behavior is also found for semiflexible polymers, phenylcarbamate derivatives of cellulose and amylose. [11][12][13] Although there is little research on the phase separation behavior of semiflexible nonlinear polymers, cyclic amylose tris(n-butylcarbamate) has an appreciably positive second virial coefficient in the theta solvent of the linear chain, 14 meaning that the solubility of the cyclic polymer in the solvent is better than that of the corresponding linear chain.…”