Here are described the detectors available for GPC-IR instrument:
IR4 is the standard detector integrated by default in all the Polymer Char analytical instruments. IR4 is a dual wavelength infrared detector, which uses the principle of infrared absorption spectroscopy to measure the concentration and composition in polyolefins.
IR4 is designed to measure on-line concentration and composition in GPC/SEC, HPLC or to couple it with other separation techniques like CRYSTAF, TREF, etc., and it has been proved as the most appropriate detector for polyolefins.
When adding a composition or a carbonyls sensor, other useful information can be obtained in addition to the concentration.
IR5 MCT is a infrared detector with a flow through cell, which incorporates interference filters at five different wavelengths and a thermoelectrically cooled MCT detector with a high sensitivity (no liquid Nitrogen required).
IR5 MCT is designed to determine concentration and composition on-line in separation techniques providing high sensitivity and stability of both signals.
In 2012, the IR5 MCT detector has been fully integrated into some of Polymer Char instruments and the carefully controlled detector environment results in superb long term baseline stability.
To couple an IR5 MCT with a GPC instrument is an ideal combination for measuring very low number of branches in HDPE pipe resins thanks to its high sensitivity, which is able to distinguish differences of up to 1 branch per 1,000 atoms of carbon.
Polymer Char's highly sensitive Four Capillary Differential Bridge Viscometer is an ideal complement to the Infrared detector in some polyolefin characterization instruments such as GPC-IR.
Viscometer configuration is optimized to achieve a better performance in each technique.
Light Scattering detectors provide absolute measurement of Molar Mass. When coupling a Light Scattering to a Polymer Char instrument, complementary information can be obtained to have a more complete and precise characterization.
Light Scattering is especially effective in some techniques like GPC/SEC, for instance when searching for Long Chain Branching results among others; therefore, Polymer Char GPC-IR is designed to incorporate the most appropriate Light Scattering detector for polyolefins currently in the market: DAWN® HELEOS™ II of Wyatt Technology.
The DAWN® HELEOS™ II 8 or 18 angle is offered as an additional detector in other Polymer Char instruments such as TREF or CEF.