Comprehensive two-dimensional liquid chromatography for the characterization of functional acrylate polymers.
Comprehensive two-dimensional liquid chromatography-size-exclusion chromatography (LC x SEC) was investigated as a tool for the characterization of functional poly(methyl methacrylate) (PMMA) polymers. Ultraviolet-absorbance and evaporative light-scattering detection (ELSD) were used. A simple method to quantify ELSD data is presented. Each data point from the ELSD chromatogram can be converted into a mass concentration using experimental calibration curves. The qualitative and quantitative information obtained on two representative samples is used to demonstrate the applicability of LC x SEC for determining the mutually dependent molar-mass distributions (MMD) and functionality-type distributions (FTD) of functional polymers. The influence of the molar mass on the retention behavior in LC was investigated using LC x SEC for hydroxyl-functional PMMA polymers. The critical conditions, at which retention is--by definition--independent of molar mass, were not exactly the same for PMMA series with different end-groups. Our observations are in close agreement with theoretical curves reported in the literature. However, for practical applications of LC x SEC it is not strictly necessary to work at the exact critical solvent composition. Near-critical conditions are often sufficient to determine the mutually dependent distributions (MMD and FTD) of functional polymers.
Jiang
Xulin
X
Polymer-Analysis Group, van't Hoff Institute for Molecular Sciences, University of Amsterdam, Nieuwe Achtergracht 166, 1018 WV Amsterdam, The Netherlands. x.jiang@pharm.uu.nl
van der Horst
Aschwin
A
Lima
Vincent
V
Schoenmakers
Peter J
PJ
D002138:Calibration; D002853:Chromatography, Liquid / Q000379:methods*; D008027:Light; D019904:Polymethyl Methacrylate / Q000737:chemistry*; D012542:Scattering, Radiation; D013056:Spectrophotometry, Ultraviolet
D019904:Polymethyl Methacrylate