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Knol WC, Pirok BWJ, Peters RAH. Detection challenges in quantitative polymer analysis by liquid chromatography. J Sep Sci 2020; 44:63-87. [PMID: 32935906 PMCID: PMC7821191 DOI: 10.1002/jssc.202000768] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Revised: 09/14/2020] [Accepted: 09/14/2020] [Indexed: 12/19/2022]
Abstract
Accurate quantification of polymer distributions is one of the main challenges in polymer analysis by liquid chromatography. The response of contemporary detectors is typically influenced by compositional features such as molecular weight, chain composition, end groups, and branching. This renders the accurate quantification of complex polymers of which there are no standards available, extremely challenging. Moreover, any (programmed) change in mobile-phase composition may further limit the applicability of detection techniques. Current methods often rely on refractive index detection, which is not accurate when dealing with complex samples as the refractive-index increment is often unknown. We review current and emerging detection methods in liquid chromatography with the aim of identifying detectors, which can be applied to the quantitative analysis of complex polymers.
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Affiliation(s)
- Wouter C Knol
- Analytical Chemistry Group, van't Hoff Institute for Molecular Sciences (HIMS), Faculty of Science, University of Amsterdam, Amsterdam, The Netherlands.,Centre for Analytical Sciences Amsterdam, Amsterdam, The Netherlands
| | - Bob W J Pirok
- Analytical Chemistry Group, van't Hoff Institute for Molecular Sciences (HIMS), Faculty of Science, University of Amsterdam, Amsterdam, The Netherlands.,Centre for Analytical Sciences Amsterdam, Amsterdam, The Netherlands
| | - Ron A H Peters
- Analytical Chemistry Group, van't Hoff Institute for Molecular Sciences (HIMS), Faculty of Science, University of Amsterdam, Amsterdam, The Netherlands.,Centre for Analytical Sciences Amsterdam, Amsterdam, The Netherlands.,DSM Resins & Functional Materials, Analytical Technology Centre, Waalwijk, The Netherlands
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2
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Radebe N, Beskers T, Greyling G, Pasch H. Online coupling of thermal field-flow fractionation and Fourier transform infrared spectroscopy as a powerful tool for polymer characterization. J Chromatogr A 2019; 1587:180-188. [DOI: 10.1016/j.chroma.2018.12.012] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2018] [Revised: 12/06/2018] [Accepted: 12/09/2018] [Indexed: 11/16/2022]
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3
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LI Y, GUO R, LIU S, HE A, BAO Y, WENG S, HUANG Y, XU Y, OZAKI Y, NODA I, WU J. Use of CuO Particles as an Interface in LC-FTIR Analysis. ANAL SCI 2017; 33:105-110. [DOI: 10.2116/analsci.33.105] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- Yan LI
- Nanyang Institute of Technology
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University
| | - Ran GUO
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University
- College of Chemistry and Environmental Engineering, Shenzhen University
| | - Shengnan LIU
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University
- College of Chemistry and Material Science, Hebei Normal University
| | - Anqi HE
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University
- Ninghai Doubly Advanced Materials Co., Ltd
| | - Yanan BAO
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University
- Liaoning Technical University
| | - Shifu WENG
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University
| | | | - Yizhuang XU
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University
- Ninghai Doubly Advanced Materials Co., Ltd
| | - Yukihiro OZAKI
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University
- Department of Chemistry, School of Science, Kwansei Gakuin University
| | - Isao NODA
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University
- Department of Materials Science and Engineering, University of Delaware
| | - Jinguang WU
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University
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Lee D, Shan CLP, Meunier DM, Lyons JW, Cong R, deGroot AW. Toward absolute chemical composition distribution measurement of polyolefins by high-temperature liquid chromatography hyphenated with infrared absorbance and light scattering detectors. Anal Chem 2014; 86:8649-56. [PMID: 25117509 DOI: 10.1021/ac501477a] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Chemical composition distribution (CCD) is a fundamental metric for representing molecular structures of copolymers in addition to molecular weight distribution (MWD). Solvent gradient interaction chromatography (SGIC) is commonly used to separate copolymers by chemical composition in order to obtain CCD. The separation of polymer in SGIC is, however, not only affected by chemical composition but also by molecular weight and architecture. The ability to measure composition and MW simultaneously after separation would be beneficial for understanding the impact of different factors and deriving true CCD. In this study, comprehensive two-dimensional chromatography (2D) was coupled with infrared absorbance (IR5) and light scattering (LS) detectors for characterization of ethylene-propylene copolymers. Polymers were first separated by SGIC as the first dimension chromatography (D1). The separated fractions were then characterized by the second dimension (D2) size exclusion chromatography (SEC) with IR5 and LS detectors. The concentrations and compositions of the separated fractions were measured online using the IR5 detector. The MWs of the fractions were measured by the ratio of LS to IR5 signals. A metric was derived from online concentration and composition data to represent CCD breadth. The metric was shown to be independent of separation gradients for an "absolute" measurement of CCD breadth. By combining online composition and MW data, the relationship of MW as a function of chemical composition was obtained. This relationship was qualitatively consistent with the results by SEC coupled to IR5, which measures chemical composition as a function of logMW. The simultaneous measurements of composition and MW give the opportunity to study the SGIC separation mechanism and derive chain architectural characteristics of polymer chains.
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Affiliation(s)
- Dean Lee
- The Dow Chemical Company, Analytical Sciences R&D, 1897 Building, Midland, Michigan 48667, United States
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5
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Malik MI, Pasch H. Novel developments in the multidimensional characterization of segmented copolymers. Prog Polym Sci 2014. [DOI: 10.1016/j.progpolymsci.2013.10.005] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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6
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Chojnacka A, Kempe K, van de Ven HC, Englert C, Hoogenboom R, Schubert US, Janssen HG, Schoenmakers P. Molar mass, chemical-composition, and functionality-type distributions of poly(2-oxazoline)s revealed by a variety of separation techniques. J Chromatogr A 2012; 1265:123-32. [DOI: 10.1016/j.chroma.2012.09.080] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2012] [Revised: 09/19/2012] [Accepted: 09/20/2012] [Indexed: 10/27/2022]
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7
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Uliyanchenko E, van der Wal S, Schoenmakers PJ. Challenges in polymer analysis by liquid chromatography. Polym Chem 2012. [DOI: 10.1039/c2py20274c] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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8
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Analytical potential of mid-infrared detection in capillary electrophoresis and liquid chromatography: A review. Anal Chim Acta 2010; 679:31-42. [DOI: 10.1016/j.aca.2010.09.006] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2010] [Revised: 09/01/2010] [Accepted: 09/03/2010] [Indexed: 11/22/2022]
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9
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Kuligowski J, Carrión D, Quintás G, Garrigues S, de la Guardia M. Cubic smoothing splines background correction in on-line liquid chromatography–Fourier transform infrared spectrometry. J Chromatogr A 2010; 1217:6733-41. [DOI: 10.1016/j.chroma.2010.05.033] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2010] [Revised: 05/12/2010] [Accepted: 05/19/2010] [Indexed: 10/19/2022]
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10
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On-line preferential solvation studies of polymers by coupled chromatographic-Fourier transform infrared spectroscopic flow-cell technique. J Chromatogr A 2009; 1216:8939-46. [DOI: 10.1016/j.chroma.2009.10.062] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2009] [Revised: 10/06/2009] [Accepted: 10/23/2009] [Indexed: 11/19/2022]
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11
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Zhang Z, Saetre R. Characterization of Styrene Copolymers Using Size-Exclusion Chromatography with On-line FT-IR Viscometer Detectors. INTERNATIONAL JOURNAL OF POLYMER ANALYSIS AND CHARACTERIZATION 2007. [DOI: 10.1080/10236660701223824] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Kaal ER, Alkema G, Kurano M, Geissler M, Janssen HG. On-line size exclusion chromatography–pyrolysis-gas chromatography–mass spectrometry for copolymer characterization and additive analysis. J Chromatogr A 2007; 1143:182-9. [PMID: 17208247 DOI: 10.1016/j.chroma.2006.12.054] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2006] [Revised: 12/15/2006] [Accepted: 12/19/2006] [Indexed: 11/17/2022]
Abstract
On-line coupled size exclusion chromatography-pyrolysis gas chromatography mass spectrometry (SEC-Py-GC-MS) is studied as a novel tool for the characterization of complex polymer samples. An automated system for on-line SEC-Py-GC-MS allowing transfer of multiple fractions was developed based on stop-flow operation of the SEC dimension, syringe-based transfer of the SEC fraction to the GC instrument and solvent elimination with subsequent pyrolysis in a programmed temperature vaporization (PTV) injector. After optimization the system was applied to the characterization of a complex terpolymer composed of very similar monomers. The use of the system for combined pyrolysis and additive analyses in polycarbonate was also demonstrated. Results obtained with the new method indicate the interesting potentials of the method for detailed characterization of polymeric materials.
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Affiliation(s)
- Erwin R Kaal
- Polymer-Analysis Group, van't Hoff Institute for Molecular Sciences, University of Amsterdam, Nieuwe Achtergracht 166, 1018 WV Amsterdam, The Netherlands.
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Coulier L, Kaal E, Hankemeier T. Hyphenation of infrared spectroscopy to liquid chromatography for qualitative and quantitative polymer analysis: Degradation of poly(bisphenol A)carbonate. J Chromatogr A 2006; 1130:34-42. [PMID: 16735038 DOI: 10.1016/j.chroma.2006.04.070] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2006] [Revised: 04/18/2006] [Accepted: 04/19/2006] [Indexed: 11/19/2022]
Abstract
Hyphenation of infrared spectroscopy (IR) to liquid chromatography (LC) has been applied to study chemical changes in poly(bisphenol A)carbonate (PC) as a result of degradation. Especially coupling of LC to FTIR through solvent elimination is a sensitive approach to identify changes in functionality observed in the LC chromatograms as has been demonstrated by coupling of liquid chromatography under critical conditions (LCCC) to IR. Furthermore, an example is shown in which two-dimensional liquid chromatography, i.e. LCCC x SEC, was coupled to IR by means of a flow cell. This resulted in data sets containing most probably valuable data, but extracting relevant information from these large data sets is not straightforward at all. Therefore, multivariate data analysis (MVDA) of SEC-FTIR data was used to extract relevant data from large data sets. This approach revealed chemical differences due to degradation that could not be detected by other means. Spectral features could be identified that allowed to quantitatively predict the degradation of poly(bisphenol A)carbonate as a function of degradation conditions.
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Affiliation(s)
- Leon Coulier
- Packaging Research and Polymer Analysis Group, Analytical Sciences Department, TNO Quality of Life, Utrechtseweg 48, 3704 HE Zeist, The Netherlands.
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14
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Coulier L, Kaal E, Hankemeier T. Towards early detection of the hydrolytic degradation of poly(bisphenol A)carbonate by hyphenated liquid chromatography and comprehensive two-dimensional liquid chromatography. Polym Degrad Stab 2006. [DOI: 10.1016/j.polymdegradstab.2005.05.015] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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15
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Coulier L, Kaal ER, Hankemeier T. Comprehensive two-dimensional liquid chromatography and hyphenated liquid chromatography to study the degradation of poly(bisphenol A)carbonate. J Chromatogr A 2005; 1070:79-87. [PMID: 15861791 DOI: 10.1016/j.chroma.2005.02.067] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Size exclusion chromatography (SEC), gradient polymer elution chromatography (GPEC) and liquid chromatography at critical conditions (LC-CC) have been developed and applied to observe chemical changes in poly(bisphenol A)carbonate (PC) due to hydrolytic degradation. Especially LC-CC appeared to be very successful to observe differences in functionality of PC as result of hydrolytic degradation. Observed differences due to degradation could be identified by (semi) on-line coupling to matrix assisted laser desorption-ionization time-of-flight mass spectrometry (MALDI-TOF-MS). The differences in functionality could be attributed to the formation of different end-groups, i.e. OH end-groups. In addition, comprehensive two-dimensional liquid chromatography (2D-LC) has been applied successfully to study the hydrolytic degradation of PC. LC-CC x SEC showed that the formation of PC with different end-groups occurred over the whole molecular mass range. This information could not be obtained with the separate liquid chromatographic techniques, thereby illustrating the added value of 2D-LC.
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Affiliation(s)
- L Coulier
- Packaging Research and Polymer Analysis Group, Analytical Sciences Department, TNO Quality of Life, Utrechtseweg 48, 3704 HE Zeist, The Netherlands.
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16
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Kok SJ, Hankemeier T, Schoenmakers PJ. Comprehensive two-dimensional liquid chromatography with on-line Fourier-transform-infrared-spectroscopy detection for the characterization of copolymers. J Chromatogr A 2005; 1098:104-10. [PMID: 16314165 DOI: 10.1016/j.chroma.2005.08.058] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2004] [Revised: 08/16/2005] [Accepted: 08/19/2005] [Indexed: 10/25/2022]
Abstract
The on-line coupling of comprehensive two-dimensional liquid chromatography (liquid chromatography x size-exclusion chromatography, LC x SEC) and infrared (IR) spectroscopy has been realized by means of an IR flow cell. The system has been assessed by the functional-group analysis of a series of styrene-methylacrylate (SMA) copolymers with varying styrene content. Ultraviolet (UV) detection was used as a detection technique to verify the detection with IR. The LC x SEC-IR functional-group contour plots (comprehensive chromatograms) obtained for styrene were in agreement with the contour plots constructed from the UV signal. In addition, contour plots can be obtained from non-UV-active groups. One such plot, for the carbonyl-stretching vibration of methylacrylate (MA), is shown. Selective detection of MA proved possible using flow cell IR detection. The combination of the contour plots for styrene and MA allowed a full characterization of the copolymer and it was revealed that the present series of SMA copolymers exhibited homogeneous chemical-composition distributions (CCDs). In addition, commercially available fast-SEC columns have been assessed in this study with respect to their potential to serve as second-dimension separation columns.
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Affiliation(s)
- S J Kok
- TNO Nutrition and Food Research, Packaging Research Department, Utrechtseweg 48, 3704 HE Zeist, The Netherlands.
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Kostanski LK, Keller DM, Hamielec AE. Size-exclusion chromatography-a review of calibration methodologies. ACTA ACUST UNITED AC 2004; 58:159-86. [PMID: 14980789 DOI: 10.1016/j.jbbm.2003.10.001] [Citation(s) in RCA: 134] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Recent developments are reviewed in size exclusion chromatographic calibration methodologies, including direct calibration by using narrow and broad polymer standards and various instrumental methods (nuclear magnetic resonance, mass spectrometry, light scattering) as well as universal calibration with and without viscometry detectors, for simple and complex polymers.
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Affiliation(s)
- Leopold K Kostanski
- Chemical Engineering Department, McMaster University, 1280 Main Street West, Hamilton, Ontario, Canada L8S 4L7.
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Abstract
A characteristic feature of synthetic polymers is their dispersity in molar mass and, in many cases, chemical composition. Since dispersity is highly relevant in relation to polymer properties, ongoing efforts are being put in the development of appropriate analysis methods. In this respect, size-exclusion chromatography (SEC) is well known for the determination of molar mass distributions. Methods for chemical composition distributions are less mature than SEC and mainly include liquid chromatography and mass spectrometry and the combination of these techniques. The term chemical composition distribution is considered broad in this paper, i.e. for the chemical composition distribution of a (co)polymer backbone, for the functionality type distribution of a polymers' functional end groups, for the block length distribution of a block copolymer, for the branching distribution and for the tacticity distribution. In this paper, analysis methods for all types of chemical composition distributions are reviewed. Special attention is paid to practical requirements and common misconceptions that sometimes arise. Applications within the last 5 years are summarized.
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Affiliation(s)
- Harry J A Philipsen
- Océ, Technologies, Research and Development Department, PO Box 101, NL-5900 MA, Venlo, The Netherlands.
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Kok SJ, Wold CA, Hankemeier T, Schoenmakers PJ. Comparison of on-line flow-cell and off-line solvent-elimination interfaces for size-exclusion chromatography and Fourier-transform infrared spectroscopy in polymer analysis. J Chromatogr A 2003; 1017:83-96. [PMID: 14584693 DOI: 10.1016/j.chroma.2003.08.026] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Two commercial liquid chromatography-Fourier-transform infrared spectroscopy interfaces (LC-FTIR), viz. a flow cell and a solvent-elimination interface have been assessed for use in size-exclusion chromatography (SEC) with respect to their chromatographic integrity (i.e. peak asymmetry, chromatographic resolution), quantitative and qualitative aspects. A polycarbonate/aliphatic polyester (PC/APE) blend and a polycarbonate-co-polydimethylsiloxane (PC-co-PDMS) copolymer were selected for the assessment. Both samples were successfully and selectively analyzed. The relatively large volume of the flow cell and the inherent deposition characteristics of the solvent-elimination interface led to a comparable decrease in the chromatographic resolution. The separation of oligomers was diminished in comparison with SEC-ultra-violet (UV). However, the peak asymmetry was not significantly affected by either interface. For both interfaces, a linear relationship was obtained for the FTIR response versus the injected concentration. The sensitivity was found to be higher for the solvent-elimination interface. For the current model compounds, the flow-cell interface detection limits are worse. However, the repeatability of flow-cell SEC-FTIR, evaluated by means of four SEC-FTIR analyses of polycarbonate, was considerably better than for solvent-elimination SEC-FTIR. This is probably due to the well-defined optical path length of the sample in the flow cell. By spectral subtraction, it was very well possible to obtain qualitative (functional group) information for compound identification also with flow-cell SEC-FTIR.
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Affiliation(s)
- S J Kok
- Packaging Research Department, TNO Nutrition and Food Research, Utrechtseweg 48, 3704 HE Zeist, The Netherlands.
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van der Horst A, Schoenmakers PJ. Comprehensive two-dimensional liquid chromatography of polymers. J Chromatogr A 2003; 1000:693-709. [PMID: 12877195 DOI: 10.1016/s0021-9673(03)00495-3] [Citation(s) in RCA: 201] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The need for and the emergence of comprehensive two-dimensional liquid chromatographic separations of synthetic polymers are reviewed in this paper. LC x SEC is shown to be a particularly valuable two-dimensional technique in this domain. An improved (symmetrical) configuration based on a single 10-way switching valve is described. The use of LC x SEC to understand and optimize one-dimensional separations is illustrated, as well as the potential of the technique for the separation and characterization of functional polymers and copolymers.
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Affiliation(s)
- Aschwin van der Horst
- Polymer-Analysis Group, Department of Chemical Engineering, University of Amsterdam, Nieuwe Achtergracht 166, 1018 WVAmsterdam, The Netherlands
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