The Experts below are selected from a list of 24315 Experts worldwide ranked by ideXlab platform
Isao Noda - One of the best experts on this subject based on the ideXlab platform.
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two dimensional correlation Gel Permeation chromatography 2d gpc study of aggregate aggregate interactions during polymerization of 3 triethoxysilyl propyl terminated polystyrene
Polymer Journal, 2004Co-Authors: Keita Suzuki, Kenichi Izawa, Hirofumi Okabayashi, Isao Noda, Junichi Oku, Charmian J OconnorAbstract:Two-dimensional Correlation Gel Permeation Chromatography (2D GPC) Study of Aggregate–Aggregate Interactions during Polymerization of 3-(Triethoxysilyl)propyl-terminated Polystyrene
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2d Gel Permeation chromatography 2d gpc correlation studies of the growth process for perfluoro octyltriethoxysilane polymer aggregates
Physical Chemistry Chemical Physics, 2002Co-Authors: Kenichi Izawa, Toshiaki Ogasawara, Hideki Masuda, Hirofumi Okabayashi, Charmian J Oconnor, Isao NodaAbstract:A novel analytical technique, two-dimensional correlation Gel Permeation chromatography (2D correlation GPC), has been used to elucidate intricate details of the two-step (I and II) polymerization of 1H,1H,2H,2H-perfluoro-octyltriethoxysilane (PFOTES) catalyzed by 0.5, 1.0 and 2.0 M HCl·H2O over a time period of 600–14 400 s. The 2D GPC correlation results demonstrate that each elution band (particularly, in step II) consists of two (reactive and nonreactive) components and that a higher HCl concentration enhances the correlation of the reactive component with other bands. It is suggested that rapid growth of the polymeric aggregates in step II may be caused by the appearance of these reactive components.
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two dimensional correlation Gel Permeation chromatography 2d gpc study of 1h 1h 2h 2h perfluorooctyltriethoxysilane sol Gel polymerization process
Journal of Physical Chemistry B, 2002Co-Authors: Kenichi Izawa, Toshiaki Ogasawara, Hideki Masuda, Hirofumi Okabayashi, And Charmian J Oconnor, Isao NodaAbstract:The novel analytical technique, two-dimensional (2D) correlation analysis, has been applied to a set of time-resolved Gel Permeation chromatography (GPC) profiles of 1H,1H,2H,2H-perfluorooctyltriethoxysilane (PFOTES) to investigate intricate details of the process of its polymerization, catalyzed by 1 M HCl·H2O, over a thirty minute period. In particular, the splitting behavior of the correlation cross-peaks and their intensity variation have been examined in detail, leading to the conclusion that the mechanism of the growth process of polymeric aggregates is strongly reflected in the patterns of the observed spectra. The 2D correlation GPC method, which has been used to follow the time-dependence of the split components, has proved to be a powerful tool in elucidation of the reaction mechanism.
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two dimensional correlation Gel Permeation chromatography study of octyltriethoxysilane sol Gel polymerization process
Macromolecules, 2002Co-Authors: Kenichi Izawa, Toshiaki Ogasawara, Hideki Masuda, Hirofumi Okabayashi, Isao NodaAbstract:A novel analytical method called two-dimensional correlation Gel Permeation chromatography (2D GPC) is introduced. In 2D GPC, generalized two-dimensional (2D) correlation analysis is combined with ...
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two dimensional correlation Gel Permeation chromatography 2d correlation gpc study of the sol Gel polymerization of octyltriethoxysilane hcl concentration dependence
PhysChemComm, 2002Co-Authors: Kenichi Izawa, Toshiaki Ogasawara, Hideki Masuda, Hirofumi Okabayashi, Charmian J Oconnor, Isao NodaAbstract:Two-dimensional correlation Gel Permeation chromatography (2D GPC) was used to elucidate intricate details of the initial ten minutes of the sol–Gel transition of n-octyltriethoxysilane (OTES), catalysed by 0.5 and 2.0 M HCl·H 2 O. The results demonstrate that the features of 2D GPC correlation spectra directly reflect the dynamic variation of reactions or interactions present during the polymerization process.
Alan Brookes - One of the best experts on this subject based on the ideXlab platform.
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polyolefin characterization in dibutoxymethane by high temperature Gel Permeation chromatography with a new evaporative light scattering detector
Polymer Testing, 2017Co-Authors: Adrian Boborodea, Alan BrookesAbstract:Abstract A new evaporative light scattering detector (ELSD) for the analysis of polyolefins by high temperature Gel Permeation chromatography (GPC) was recently introduced by Agilent Technologies. For the first time, we investigated the possibility to use this detector to measure the molecular weight distributions (MWD) of different types of polyolefins (polypropylene, linear and low-density polyethylene) in dibutoxymethane (DBM, butylal). These samples were previously characterized by GPC in trichlorobenzene (TCB) with a differential refractive index (DRI) detector in an interlaboratory study conducted by the International Union of Pure and Applied Chemistry (IUPAC) [1], and in a recent publication by GPC with the new ELSD in TCB [2]. The signal to noise of ELSD using DBM is about 10 times lower than that for TCB. However, the ELSD signal power exponent for DBM was measured as 1.35, which is much closer to unity than the value of 1.61 for TCB. After applying the required corrections to linearize the response of the ELSD signal as a function of concentration, similar average molecular weights to those measured in the interlaboratory study using DRI, were obtained for the analyzed resins.
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investigation of sample preparation for high temperature Gel Permeation chromatography using a low solvent consumption method
Polymer Testing, 2017Co-Authors: Adrian Boborodea, Alan BrookesAbstract:Abstract The study explored the optimum conditions for sample preparation of polyolefins for high temperature Gel Permeation chromatography (GPC) recommended by ASTM D 6474, and the potential for reducing solvent consumption by using columns with reduced internal diameter. A polypropylene sample with high crystallinity and high molecular weight was selected, because this is one of the most difficult polyolefins to analyze by GPC. Sequences of injections covering 20 h showed that, at 160 °C, 2 h is enough to dissolve this sample, and that the antioxidant concentration is the critical parameter in obtaining reproducible GPC results. By using one column with an internal diameter (ID) of 4.6 mm and a flow rate of 0.3 mL/min, instead of the classical set of 3 columns of 7.5 mm ID and a flow rate of 1 mL/min, the solvent consumption can be reduced to about 10%.
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Gel Permeation chromatography atmospheric pressure chemical ionization mass spectrometry for characterization of polymer additives
International Journal of Polymer Analysis and Characterization, 2017Co-Authors: Adrian Boborodea, Alan BrookesAbstract:ABSTRACTThe study presents the possibility to use Gel Permeation chromatography (GPC) with atmospheric pressure chemical ionization (APCI)-mass spectrometry for the analysis of polymer additives having molecular weights up to 2,000 g mol−1. Irganox 1010, Irganox 1035, Irganox 1076, and Irganox 3114 were analyzed in chloroform using 2.1-mm-internal-diameter GPC columns at the optimum flow rate of 50 µL min−1. Based on the chemical formula, the APCI interface combined with chlorine ionization enabled us to predict the expected mass spectrum and to build libraries without needing to inject each additive separately. Quantification limits of about 100 µg of additive in 1 g of polymer (100 ppm) can be reached using single-ion-monitoring methods based on the calculated isotope distribution.
Adrian Boborodea - One of the best experts on this subject based on the ideXlab platform.
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polyolefin characterization in dibutoxymethane by high temperature Gel Permeation chromatography with a new evaporative light scattering detector
Polymer Testing, 2017Co-Authors: Adrian Boborodea, Alan BrookesAbstract:Abstract A new evaporative light scattering detector (ELSD) for the analysis of polyolefins by high temperature Gel Permeation chromatography (GPC) was recently introduced by Agilent Technologies. For the first time, we investigated the possibility to use this detector to measure the molecular weight distributions (MWD) of different types of polyolefins (polypropylene, linear and low-density polyethylene) in dibutoxymethane (DBM, butylal). These samples were previously characterized by GPC in trichlorobenzene (TCB) with a differential refractive index (DRI) detector in an interlaboratory study conducted by the International Union of Pure and Applied Chemistry (IUPAC) [1], and in a recent publication by GPC with the new ELSD in TCB [2]. The signal to noise of ELSD using DBM is about 10 times lower than that for TCB. However, the ELSD signal power exponent for DBM was measured as 1.35, which is much closer to unity than the value of 1.61 for TCB. After applying the required corrections to linearize the response of the ELSD signal as a function of concentration, similar average molecular weights to those measured in the interlaboratory study using DRI, were obtained for the analyzed resins.
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investigation of sample preparation for high temperature Gel Permeation chromatography using a low solvent consumption method
Polymer Testing, 2017Co-Authors: Adrian Boborodea, Alan BrookesAbstract:Abstract The study explored the optimum conditions for sample preparation of polyolefins for high temperature Gel Permeation chromatography (GPC) recommended by ASTM D 6474, and the potential for reducing solvent consumption by using columns with reduced internal diameter. A polypropylene sample with high crystallinity and high molecular weight was selected, because this is one of the most difficult polyolefins to analyze by GPC. Sequences of injections covering 20 h showed that, at 160 °C, 2 h is enough to dissolve this sample, and that the antioxidant concentration is the critical parameter in obtaining reproducible GPC results. By using one column with an internal diameter (ID) of 4.6 mm and a flow rate of 0.3 mL/min, instead of the classical set of 3 columns of 7.5 mm ID and a flow rate of 1 mL/min, the solvent consumption can be reduced to about 10%.
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new evaporative light scattering detector for high temperature Gel Permeation chromatography
International Journal of Polymer Analysis and Characterization, 2017Co-Authors: Adrian Boborodea, Stephen OdonohueAbstract:ABSTRACTA new evaporative light scattering detector (ELSD) for the analysis of polyolefins by high temperature Gel Permeation chromatography (GPC) was recently introduced by Agilent Technologies. For the first time, we investigated the possibility to use this detector in order to measure the molecular weight distributions (MWD) of different type of polyolefines (polypropylene, linear and low density polyethylene). These samples were previously characterized by GPC with a differential refractive index (DRI) detector by several companies, in an interlaboratory study conducted by International Union of Pure and Applied Chemistry (IUPAC) [1]. The excellent baseline stability of ELSD as compared with DRI was reflected in a better reproducibility of the measured average molecular weights. More importantly, after applying required corrections to linearize the response of the ELSD as a function of concentration, we obtained similar results as previously obtained with DRI for the MWD of analyzed resins, covering t...
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assessing the suitability of a green solvent for Gel Permeation chromatography mass spectrometry analysis
International Journal of Polymer Analysis and Characterization, 2017Co-Authors: Adrian Boborodea, Stephen OdonohueAbstract:ABSTRACTThe study presents the possibility of performing the analysis of oligomeric structures and polymer additives by Gel Permeation chromatography (GPC) with atmospheric pressure chemical ionization (APCI) mass spectrometry (MS) in dibuthoxymethane (DBM, butylal), a halogen-free and less hazardous solvent than typically used chloroform and tetrahydrofuran. Polystyrene oligomers and Irganox® additives were analyzed in DBM using 2.1 mm internal diameter GPC columns, allowing to decrease the flow rate down to 50 µL/min, compatible with APCI–MS interface. The ionization was controlled by adding 1% chloroform in DBM to obtain (M+Cl)− adducts, allowing a fast optimization of method parameters.
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Gel Permeation chromatography atmospheric pressure chemical ionization mass spectrometry for characterization of polymer additives
International Journal of Polymer Analysis and Characterization, 2017Co-Authors: Adrian Boborodea, Alan BrookesAbstract:ABSTRACTThe study presents the possibility to use Gel Permeation chromatography (GPC) with atmospheric pressure chemical ionization (APCI)-mass spectrometry for the analysis of polymer additives having molecular weights up to 2,000 g mol−1. Irganox 1010, Irganox 1035, Irganox 1076, and Irganox 3114 were analyzed in chloroform using 2.1-mm-internal-diameter GPC columns at the optimum flow rate of 50 µL min−1. Based on the chemical formula, the APCI interface combined with chlorine ionization enabled us to predict the expected mass spectrum and to build libraries without needing to inject each additive separately. Quantification limits of about 100 µg of additive in 1 g of polymer (100 ppm) can be reached using single-ion-monitoring methods based on the calculated isotope distribution.
Kenichi Izawa - One of the best experts on this subject based on the ideXlab platform.
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two dimensional correlation Gel Permeation chromatography 2d gpc study of aggregate aggregate interactions during polymerization of 3 triethoxysilyl propyl terminated polystyrene
Polymer Journal, 2004Co-Authors: Keita Suzuki, Kenichi Izawa, Hirofumi Okabayashi, Isao Noda, Junichi Oku, Charmian J OconnorAbstract:Two-dimensional Correlation Gel Permeation Chromatography (2D GPC) Study of Aggregate–Aggregate Interactions during Polymerization of 3-(Triethoxysilyl)propyl-terminated Polystyrene
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2d Gel Permeation chromatography 2d gpc correlation studies of the growth process for perfluoro octyltriethoxysilane polymer aggregates
Physical Chemistry Chemical Physics, 2002Co-Authors: Kenichi Izawa, Toshiaki Ogasawara, Hideki Masuda, Hirofumi Okabayashi, Charmian J Oconnor, Isao NodaAbstract:A novel analytical technique, two-dimensional correlation Gel Permeation chromatography (2D correlation GPC), has been used to elucidate intricate details of the two-step (I and II) polymerization of 1H,1H,2H,2H-perfluoro-octyltriethoxysilane (PFOTES) catalyzed by 0.5, 1.0 and 2.0 M HCl·H2O over a time period of 600–14 400 s. The 2D GPC correlation results demonstrate that each elution band (particularly, in step II) consists of two (reactive and nonreactive) components and that a higher HCl concentration enhances the correlation of the reactive component with other bands. It is suggested that rapid growth of the polymeric aggregates in step II may be caused by the appearance of these reactive components.
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two dimensional correlation Gel Permeation chromatography 2d gpc study of 1h 1h 2h 2h perfluorooctyltriethoxysilane sol Gel polymerization process
Journal of Physical Chemistry B, 2002Co-Authors: Kenichi Izawa, Toshiaki Ogasawara, Hideki Masuda, Hirofumi Okabayashi, And Charmian J Oconnor, Isao NodaAbstract:The novel analytical technique, two-dimensional (2D) correlation analysis, has been applied to a set of time-resolved Gel Permeation chromatography (GPC) profiles of 1H,1H,2H,2H-perfluorooctyltriethoxysilane (PFOTES) to investigate intricate details of the process of its polymerization, catalyzed by 1 M HCl·H2O, over a thirty minute period. In particular, the splitting behavior of the correlation cross-peaks and their intensity variation have been examined in detail, leading to the conclusion that the mechanism of the growth process of polymeric aggregates is strongly reflected in the patterns of the observed spectra. The 2D correlation GPC method, which has been used to follow the time-dependence of the split components, has proved to be a powerful tool in elucidation of the reaction mechanism.
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two dimensional correlation Gel Permeation chromatography study of octyltriethoxysilane sol Gel polymerization process
Macromolecules, 2002Co-Authors: Kenichi Izawa, Toshiaki Ogasawara, Hideki Masuda, Hirofumi Okabayashi, Isao NodaAbstract:A novel analytical method called two-dimensional correlation Gel Permeation chromatography (2D GPC) is introduced. In 2D GPC, generalized two-dimensional (2D) correlation analysis is combined with ...
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two dimensional correlation Gel Permeation chromatography 2d correlation gpc study of the sol Gel polymerization of octyltriethoxysilane hcl concentration dependence
PhysChemComm, 2002Co-Authors: Kenichi Izawa, Toshiaki Ogasawara, Hideki Masuda, Hirofumi Okabayashi, Charmian J Oconnor, Isao NodaAbstract:Two-dimensional correlation Gel Permeation chromatography (2D GPC) was used to elucidate intricate details of the initial ten minutes of the sol–Gel transition of n-octyltriethoxysilane (OTES), catalysed by 0.5 and 2.0 M HCl·H 2 O. The results demonstrate that the features of 2D GPC correlation spectra directly reflect the dynamic variation of reactions or interactions present during the polymerization process.
Brice Bouyssiere - One of the best experts on this subject based on the ideXlab platform.
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study of very high molecular weight cluster presence in thf solution of asphaltenes and subfractions a1 and a2 by Gel Permeation chromatography with inductively coupled plasma mass spectrometry
Energy & Fuels, 2020Co-Authors: Genesis Gonzalez, Socrates Acevedo, Jimmy Castillo, Orlando Villegas, Maria Antonieta Ranaudo, Karina Guzman, Miguel Orea, Brice BouyssiereAbstract:Super high molecular weight (SHMW) asphaltenes aggregates, hereafter called asphaltenes clusters, have been observed for the first-time using Gel Permeation chromatography with inductively coupled ...
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study of very high molecular weight cluster presence in thf solution of asphaltenes and subfractions a1 a2 by Gel Permeation chromatography with inductively coupled plasma mass spectrometry
Energy & Fuels, 2020Co-Authors: Genesis Gonzalez, Socrates Acevedo, Jimmy Castillo, Orlando Villegas, Maria Antonieta Ranaudo, Karina Guzman, Miguel Orea, Brice BouyssiereAbstract:Super high molecular weight (SHMW) asphaltenes aggregates, hereafter called asphaltenes clusters, have been observed for the first-time using Gel Permeation chromatography with inductively coupled ...
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probing aggregation tendencies in asphaltenes by Gel Permeation chromatography part 1 online inductively coupled plasma mass spectrometry and offline fourier transform ion cyclotron resonance mass spectrometry
Energy & Fuels, 2020Co-Authors: Jonathan C Putman, Remi Moulian, Caroline Barreremangote, Ryan P Rodgers, Brice Bouyssiere, Pierre Giusti, Alan G MarshallAbstract:This study probes the nanoaggregation behavior of asphaltenes by Gel Permeation chromatography (GPC). Compounds containing sulfur, vanadium, and nickel were monitored online with elemental detectio...
