Full adsorption/desorption chromatography

Nguyen and co-workers [110, 111] used adsorption/desorption chromatography to physically separate binary component blends of PS with PMMA and PS with polyvinyl acetate (PVAc). This technique was coupled to SEC in order to separate the blend components by size. Full adsorption/desorption chromatography has been applied... 

The occurence of the complete adsorption of macromolecules forms a base of the full adsorption-desorption liquid chromatography-like separation method, FAD (Berek and Nguyen, 1998). A very weak mobile phase is employed, which acts as an adsorb for n-1 sample constituents. They are completely retained within the appropriate full adsorption-desorption column packed with nonporous particles. The unretained sample constituent is directly forwarded to an online SEC column for its molecular characterization. In the next stage, eluent strength is stepwise increased and sample constituents are successively one-by-one desorbed and forwarded into the SEC column. Successful separation of up to six distinct polymers with help of FAD method was reported. In the FAD method, solvents are chosen so that they always act as a desorb just for one sample constituent. 

Nguyen, S.H. Berek, D. Chiantore, O. Reconcentration of diluted polymer solutions by full adsorption/desorption procedure-1. Eluent switching approach studied by size exclusion chromatography. Polymer 1998, 39 (21), 5127-5132. 

Polymer Structure and Characterization, in separation science, the phenomenon of adsorption coupled with size-exclusion chromatography (SEC) has been applied to rapidly separate and characterize polymers. In this technique, called full adsorption-desorption/SEC coupling (FAD/SEC), all the components of a polymer blend are initially adsorbed onto an adsorbent. Then each component is displaced using a suitable small-molecule displacer and sent into the SEC column to characterize their size and mass distribution. This approach also finds application in characterizing copolymers having complex architecture (63). 

Du5 an Berek, Son Hoai Nguyen, and Gdrard Hild Molecular characterization of block copolymers by means of liquid chromatography /. Potential and limitations of full adsorption-desorption procedure in separation of block copolymers, Eur. Polym. J., 36(6)... 

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