(181bl) A More Detail Study on Tgic, Simultaneous Effect of Molecular Weight, Comonemer Content and Comonomer Type | AIChE

(181bl) A More Detail Study on Tgic, Simultaneous Effect of Molecular Weight, Comonemer Content and Comonomer Type

Authors 

Badri, A. - Presenter, University of Alberta
Mehdiabadi, S., University of Alberta
Soares, J., University of Alberta

Abstract

The chemical composition distribution of polyolefins is a crucial parameter to be determined that influences performance of industrial polyolefins. There are different methods to analyze the chemical composition distribution, the majority of which are crystallization based, such as temperature rising elution fractionation (TREF) crystallization analysis fractionation (CRYSTAF) and crystallization elution fractionation (CEF). An alternative method for the characterization of amorphous polymer is Temperature Gradient Interaction Chromatography (TGIC). TGIC can measure comonomer content in polyolefins up to 50 % by mole in a reasonably short period of time. In TGIC, the peak temperature can be correlated to the comonomer content. Previously, researchers have introduced individual calibration curves for some α-olefins such as 1-hexene, 1-octene and 1-dodecene. In order to cancel the effect of molecular weight on the calibration curves, results of the previous studies have been limited to high molecular weight polymers (above 25000).

In an attempt to generate a universal calibration curves covering a broader range of molecular weight, we replaced the TGIC column packing with non-porous materials to eliminate the size exclusion effect and limitation of molecular weight range.

For different α-olefins absorbed onto non-porous column, various calibration curves are generated for low molecular weight (<25000) samples, and based on these calibration curves, an empirical equation was introduced. Our calibration curve equation is presented as a function of copolymers molecular weight, comonomer content (CC) and the type of comonomer (α-olefin: 1-hexene, 1-octene and 1-decene).