Advantages of Infrared Detection in GPC of Polyolefins

In this application note IR detection is used for the analysis of the molar mass distribution of polyethylene and polypropylene resins, as an alternative to GPC/SEC techniques. It presents data collected from IR detectors, based on narrow band interference filters used to select specific wavelengths. The main advantages of the filter-based IR technique as concentration detection in polyolefin analysis include high sensitivity, stability, the ability to work in staggered injection mode and low detection limit. In addition, this IR detection technology is capable of detecting chemical composition, so short chain branching is quantified with high sensitivity across the molar mass distribution, complementing the microstructure information gathered in the GPC/SEC analysis.