Gel permeation chromatography followed by pyrolysis–gas chromatography–mass spectrometry via a solvent-evaporative interface

Zhu, William; Allaway, James R.

doi:10.1016/j.chroma.2004.08.148

Cited by 9 publications

(5 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For HPer DSC sample preparation an aluminum foil was wrapped around the germanium disk in such a way as to ensure good contact with the disk, with the opaque side of the foil being used for collection of the polymer deposits. The surface roughness of the opaque side of the foil enables comparatively higher adhesion as compared to the glossy side of the Al foil . The bulk sample was collected by deposition of the entire sample at a single point on the germanium disk (no rotation).…”

Section: Methodsmentioning

confidence: 99%

“…The surface roughness of the opaque side of the foil enables comparatively higher adhesion as compared to the glossy side of the Al foil. 32 The bulk sample was collected by deposition of the entire sample at a single point on the germanium disk (no rotation). All the samples for SEC-FTIR and SEC-HPer DSC were prepared under the same deposition and cooling conditions in order to ensure comparable sample and thermal histories.…”

Section: ■ Experimental Sectionmentioning

confidence: 99%

See 1 more Smart Citation

Multidimensional Analysis of the Complex Composition of Impact Polypropylene Copolymers: Combination of TREF, SEC-FTIR-HPer DSC, and High Temperature 2D-LC

et al. 2012

View full text Add to dashboard Cite

A new multidimensional fractionation technique, temperature rising elution fractionation (TREF) combined with high temperature size exclusion chromatography FTIR (HT-SEC-FTIR), HT-SEC-DSC and high temperature two-dimensional liquid chromatography (HT-2D-LC) is used for the comprehensive analysis of a commercial impact polypropylene copolymer. HT-SEC-FTIR provides information regarding the chemical composition and crystallinity as a function of molar mass. Thermal analysis of selected SEC fractions yields the melting and crystallization behavior of these fractions which is related to the chemical heterogeneity of this complex copolymer. The thermal analysis of the fractions is conducted using a novel DSC method  high speed or high performance differential scanning calorimetry (HPer DSC) -that allows measuring of minute amounts of material down to micrograms. The most interesting and complex "midelution temperature" TREF fraction (80 °C) of this copolymer is a complex mixture of ethylene-propylene copolymers (EPC's) with varying ethylene and propylene contents and sequence length distributions, as well as iPP. High temperature solvent gradient HPLC has been used to show that there is a significant amount of PE homopolymer and EPC's containing long ethylene sequences in this TREF fraction. High temperature 2D-LC analysis reveals the complete separation of this TREF fraction according to the chemical composition of each component along with their molar mass distributions.

show abstract

Section: Methodsmentioning

confidence: 99%

Section: ■ Experimental Sectionmentioning

confidence: 99%

Multidimensional Analysis of the Complex Composition of Impact Polypropylene Copolymers: Combination of TREF, SEC-FTIR-HPer DSC, and High Temperature 2D-LC

et al. 2012

View full text Add to dashboard Cite

show abstract

“…Zhu et al. applied an evaporative interface that deposited SEC effluent on a rotating aluminum foil, and sections of the foils were excised and subjected to pyrolysis‐GC [133].…”

Section: Detectors In Polymer Lc and Their Strengths And Weaknessesmentioning

confidence: 99%

Detection challenges in quantitative polymer analysis by liquid chromatography

Knol

Pirok

Peters

2020

J of Separation Science

View full text Add to dashboard Cite

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.

show abstract

“…lipids, proteins, and pigments) and the target compounds especially prior to the GC or LC analysis. Additionally, it is a nondestructive procedure that reduces the downtime of instruments and extends the lifetime of columns since the interferences are eluted first . However, some overlap of co‐extractives with the analytes fraction typically occurs and an additional cleanup step is necessary .…”

Section: Introductionmentioning

confidence: 99%

Comparison of different sample pre‐treatments for multi‐residue analysis of organochlorine and pyrethroid pesticides in chrysanthemum by gas chromatography with electron capture detection

Xue

Liu

et al. 2013

J of Separation Science

View full text Add to dashboard Cite

The widespread use of insecticides in Chinese herbal medicines has created a compelling need for the development of a multiresidue analytical method to help assure herbs safety. The operating variables affecting the performance of the multiresidue analysis of 34 organochlorine and 12 pyrethroid pesticides in chrysanthemum, a widely used kind of Chinese herbal medicines, were evaluated. Three different extraction solvents including n-hexane and its mixtures with acetone and petroleum ether were compared, and n-hexane was found to be an appropriate option. A combination of gel permeation chromatography and SPE was selected as the optimum cleanup, in comparison with dispersive SPE, or the two former methods alone. The determination of the 46 pesticide residues in the spiked chrysanthemum samples was performed by GC with electron capture detection. The average recoveries ranged from 71.3 to 102.6% with RSDs of 1.4-15.7% for all of the pesticides. The LOQs were in the range of 0.0015-0.2 mg/kg, while the LODs were between 0.0005 and 0.1 mg/kg. The satisfactory accuracy, and precision, in combination with a good separation and few interferences, have demonstrated the strong potential of this technique for its application in chrysanthemum analysis.

show abstract

Gel permeation chromatography followed by pyrolysis–gas chromatography–mass spectrometry via a solvent-evaporative interface

Cited by 9 publications

References 16 publications

Multidimensional Analysis of the Complex Composition of Impact Polypropylene Copolymers: Combination of TREF, SEC-FTIR-HPer DSC, and High Temperature 2D-LC

Multidimensional Analysis of the Complex Composition of Impact Polypropylene Copolymers: Combination of TREF, SEC-FTIR-HPer DSC, and High Temperature 2D-LC

Detection challenges in quantitative polymer analysis by liquid chromatography

Comparison of different sample pre‐treatments for multi‐residue analysis of organochlorine and pyrethroid pesticides in chrysanthemum by gas chromatography with electron capture detection

Contact Info

Product

Resources

About