Fractionation of Ethylene/1-Octene Copolymers by High-Temperature Thermal Gradient Interaction Chromatography
A, Alghyamah, Abdulaziz . 2013
High-temperature thermal gradient interaction chromatography (HT-TGIC) was recently introduced into the area of polyolefin analysis. This new technique uses commercially available Hybercarb columns to separate polyolefin chains based on their interaction with the porous graphitic carbon stationary phase in a temperature gradient mode. In this paper, a systematic study of HT-TGIC operation conditions is presented for ethylene/1-octene copolymers and their blends. One of the objectives of this investigation is to identify the best set of conditions that maximize peak separation of copolymers in a binary blend. Although the chromatograms of individual resins and their blends are independent of the cooling rate, it will be shown that sample volume (column loading) and heating rate during the elution cycle affect the peak separation of the components in binary blends.
Polyolefins made with Ziegler–Natta catalysts have non-uniform distributions of molecular weight (MWD) and chemical composition (CCD). The MWD is usually measured by high-temperature gel…
Heterogeneous Ziegler-Natta catalysts produce polyolefins that have broad distributions of molecular weight (MWD) and chemical composition (CCD).
Temperature rising elution fractionation (TREF) and crystallization analysis fractionation (CRYSTAF) fractionate semicrystalline polymers according to their crystallizabilities from dilute…