Multi angle light scattering detector

Figure 2.2 Typical setup of size-exclusion chromatography equipped with triple detection for determination of the moiecuiar weight of polymers without the need for prerequisite calibration. DRi, differential refractive index detector DV, differentiai viscometer I, injector MALS, multi-angle light-scattering detector (depending on the model, the scattered light is measured at 3 or 18 different angles) P, pump. The central unit includes a computer and software.

Figure 6.12 is an example of a molar mass distribution of a cationic copolymer floccu-lant of acrylamide measured using a SEC system coupled to a differential refractive index detector and a multi-angle light scattering detector. 

Malvern Compact Goniometer System (CGS-3) is a multi-angle light scattering spectrometer. The detector scans a sample cell from an angle of 12° to 152° with an angular resolution of 0.025°. 

Figure 12 illustrates an example of direct molar mass measurement by lightscattering in a G PC experiment for a poly(vinyl butyral) sample. For each analytical fraction (elution volume slice), the LS detector determines the correct and subsequently the molar mass distribution can be determined without any further assumptions. Obviously, this sample contains species of very different molar mass and structure, as can be further elucidated by molecular size measurement, which is possible from the multi-angle light-scattering data analysis (cf Fig. 13). 

Medium and high temperature asymmetrical flow FFF (MT-AF4 and HT-AF4) systems have been developed and distributed by Postnova Analytics (Landsberg/ Lech, Germany). HT-AF4 has been specifically developed for the separation and characterization of high molar mass polyolefins. Different detectors such as infrared (IR), refractive index (RI), multi-angle light scattering (MALS) and viscometry were applied. 

FIGURE 6.4 Comparison of Shodex GPC UT column and conventional-type column. Column Left Shodex GPC UT-806M X 2, 8 mm i.d. X 300 mm X 2. Right Conventional type column X 2, 7.8 mm i.d. X 300 mm x 2. Eluent 0.1% BHT in ODCB. Flow rate 1.0 mL/min. Detector Rl, MALLS (multi-angle laser light scattering detector). Column temp. I45°C. Sample High-density polyethylene. 

FIGURE 6.39 Hydroxyethyl cellulose. Column Left Shodex OHpak SB-806 HQ, 8.0 mm i.d. x 300 mm. Right Shodex Asahipak GF-710 HQ, 7.6 mm i.d. x 300 mm. Eluent 100 mA1 NaNOj. Flow rate 1.0 mL/min. Detector Multi-angle laser light scattering detector. Column temp. 40°C. Sample 0.05%, 200 /iL, Hydroxyethyl cellulose. 

Determined by SEC analysis using a multi-angle laser light scattering detector. 

Fig. 3 GPC setup for functional group profiling. RI refractive index detector Fluorescence fluorescence detector MALLS multi-angle laser light scattering detector...

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