Premium
The fractal calibration method applied to the characterization of polymers in solvent mixtures and in mixed gel packings by SEC
Author(s) -
Porcar Iolanda,
GarcíaLopera Rosa,
Abad Concepción,
Campos Agustín
Publication year - 2007
Publication title -
journal of separation science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.72
H-Index - 102
eISSN - 1615-9314
pISSN - 1615-9306
DOI - 10.1002/jssc.200700063
Subject(s) - calibration curve , fractal dimension , calibration , fractal , polymer , characterization (materials science) , molar mass , standard deviation , solvent , size exclusion chromatography , elution , chromatography , analytical chemistry (journal) , chemistry , materials science , mathematics , statistics , nanotechnology , mathematical analysis , organic chemistry , detection limit , enzyme
The size‐exclusion chromatographic (SEC) behaviour of different solvent/polymer systems in three packing sets has been analysed from fractal considerations. The three‐column sets studied are specifically formed by: (i) ‘pure’ μ‐styragel, (ii) ‘mixed’ TSK Gel H HR + XL + HR and (iii) mixed TSK Gel H XL + HR + XL . The experimental data reveals that in most of the systems assayed the classical universal calibration (UC) is not fulfilled, denoting the existence of secondary effects accompanying the main SEC mechanism. In order to obtain an accurate characterization of different polymers eluted in solvent mixtures and/or mixed packings, the use of a reliable and trusted calibration curve is required. In this sense, two alternative procedures have been analysed: the specific (SC) and the fractal (FC) calibrations. The results have evidenced that the use of the FC instead of the classical universal method diminishes up to nine times (in the case of the μ‐styragel set) the mean deviation on the calculated molar mass with respect to the value given by the supplier. In the case of TSK Gel‐based sets, the mean deviation is reduced to the half. The SC curve made with standards of the sample under study also reduces the mean deviation values but needs a broad set of narrow standards, whereas the fractal approach only needs one polymeric sample to build up the calibration curve.