Toward Absolute Chemical Composition Distribution Measurement of Polyolefins by High-Temperature Liquid Chromatography Hyphenated with Infrared Absorbance and Light Scattering Detectors

2014 ◽  
Vol 86 (17) ◽  
pp. 8649-8656 ◽  
Author(s):  
Dean Lee ◽  
Colin Li Pi Shan ◽  
David M. Meunier ◽  
John W. Lyons ◽  
Rongjuan Cong ◽  
...  
Keyword(s):  
Liquid Chromatography ◽  
High Temperature ◽  
Light Scattering ◽  
Chemical Composition ◽  
Composition Distribution ◽  
Distribution Measurement ◽  
Chemical Composition Distribution ◽  
Temperature Liquid

High-temperature gradient HPLC and LC-NMR for the analysis of complex polyolefins

2008 ◽  
Vol 80 (8) ◽  
pp. 1747-1762 ◽  
Author(s):  
Harald Pasch ◽  
Lars-Christian Heinz ◽  
Tibor Macko ◽  
Wolf Hiller
Keyword(s):  
High Temperature ◽  
Chemical Composition ◽  
Temperature Gradient ◽  
Molar Mass ◽  
Size Exclusion ◽  
Copolymer Composition ◽  
Composition Distribution ◽  
High Temperature Gradient ◽  
Chemical Composition Distribution ◽  
On Line

The synthesis and characterization of polyolefins continues to be one of the most important areas for academic and industrial polymer research. One consequence of the development of new "tailor-made" polyolefins is the need for new and improved analytical techniques for the analysis of polyolefins with respect to molar mass and chemical composition distribution. The present article briefly reviews different new and relevant techniques for polyolefin analysis. Crystallization analysis fractionation is a powerful new technique for the analysis of short-chain branching in linear low-density polyethylene (LLDPE) and the analysis of polyolefin blends and copolymers regarding chemical composition. For the fast analysis of the chemical composition distribution, a new high-temperature gradient high-performance liquid chromatography (HPLC) system has been developed. The efficiency of this system for the separation of various olefin copolymers is demonstrated. The correlation between molar mass and chemical composition can be accessed by on-line coupling of high-temperature size exclusion chromatography (HT-SEC) and 1H NMR spectroscopy. It is shown that the on-line NMR analysis of chromatographic fractions yields information on microstructure and tacticity in addition to molar mass and copolymer composition.

Sign in / Sign up

Export Citation Format

Share Document