Comprehensive Two-Dimensional Liquid Chromatography of Stereoregular Poly(Methyl Methacrylates) for Tacticity and Molar Mass Analysis

Abstract

For the first time, stereoregular poly(methyl methacrylates) (PMMAs) were separated according to tacticity on a carbon-based stationary phase using solvent gradient interaction chromatography (SGIC). This stationary phase provides superior separation capabilities, enabling the baseline separation of highly isotactic and syndiotactic PMMAs of different molar masses. Two-dimensional liquid chromatography was performed with the SGIC method separating, according to tacticity in the first dimension coupled to size-exclusion chromatography separating according to molar mass in the second dimension, thus providing comprehensive information on both microstructure and molar mass.

Fraction transfer process in on‐line comprehensive two‐dimensional liquid‐phase separations

“…The “classical” eight‐port valve with the 100 μL loops has recently been applied for LC × LC separation of polymers . Moreover, the four‐port duo valves have been employed in the analyses of synthetic dyes , surfactants , polymers , natural antioxidants , pharmaceutically important compounds , peptides , glycosides , and digests of monoclonal antibodies . The combination of the four‐port duo valve with two eight‐column selector valves equipped with 40 μL sampling loops has been used for the analysis of biopharmaceuticals as reported by Stoll et al.…”

Advanced fractionation methods for the microstructure analysis of complex polymers

“…While there were slight differences in the curves of different stereoregular PMMAs, unfortunately, the Figure 5. Comprehensive two-dimensional liquid chromatography contour diagram of a quaternary blend of it-PMMA 4890, it-PMMA 12000, st-PMMA 7870, and st-PMMA 24000 showing the solvent gradient interaction chromatography (SGIC) and size exclusion chromatography (SEC) projections, all molar masses in g/mol (reprinted from Maiko et al [46] with permission). This figure is available in colour online at wileyonlinelibrary.com/journal/pat Figure 6.…”

“…Very recently, the microstructure separation of PMMA has been revisited by Maiko et al and Hehn et al For the solvent gradient interaction chromatography (SGIC) separation, a novel stationary phase, Hypercarb, has been used. Hypercarb is a spherical graphitic material that gave superior separation of syndiotactic and isotactic PMMA as can be seen in Fig.…”

“…Overlays of high‐performance liquid chromatography chromatograms of syndiotactic and isotactic PMMAs (st‐PMMA 4900 + st‐PMMA 60150 and it‐PMMA 4890 + it‐PMMA 12000) (a) and (st‐PMMA 24000 + it‐PMMA 12000) (b), all molar masses in g/mol (reprinted from Maiko et al with permission). ELSD, evaporative light scattering detector; PS, polymer standards service; PL, polymer labs.…”

Comprehensive two-dimensional liquid chromatographic analysis of anthocyanins

“…The technique has found application in various fields, including in the separation of complex biological samples [132], polymers [133][134][135][136], natural products [130,137,138], peptides [139,140], biomolecules [141], proteins [142], food [143], wine [144,145] etc. In this section, a brief overview of some application of LC×LC for phenolic analysis will be presented.…”