Light scattering from cylindrical cells in the `Sofica' photometer

Ahad, E; Jennings, B. R.

doi:10.1088/0022-3727/3/10/422

Cited by 5 publications

(1 citation statement)

References 10 publications

(11 reference statements)

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“…Hence, if samples are measured in solvents different from that of the absolute calibration solvent, a correction for this effect must be made, which depends both on the cell geometry, and the solvents used. This effect has long been recognized (12,13). In the Wyatt Dawn F longitudinal, cylindrical flow cell, it essentially amounts to the ratio of the index of refraction of the sample pure solvent to that of the reference solvent (14).…”

Section: _47?n 2 {Dnldcfmentioning

confidence: 99%

Coupled Multiangle Light-Scattering and Viscosimetric Detectors for Size Exclusion Chromatography with Application to Polyelectrolyte Characterization

Reed

1996

ACS Symposium Series

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Theoretical and technical aspects of coupled multi-angle light scattering (MALLS), refractometric and viscosimetric detectors for SEC applications are considered. Absolute mass, radius of gyration and reduced viscosity distributions are obtained in this configuration, and an example application is made to characterizing water soluble polyelectrolytes. This characterization also includes illustrations of polymer form factors, interparticle structure factors, the failure of 'universal calibration', and a comparison of low angle light scattering (LALLS) and MALLS. Finally, a summary of sources of systematic and random errors is given, with estimates of the effects of each source on the characterization parameters.Polydispersity has long been the bane of macromolecular characterization. Different techniques applied to unfractionated batches' of polymer, such as static and dynamic light scattering, osmotic pressure and viscometry, all yield different averages over the mass distribution for the quantities they measure. The averages are often difficult to interpret and compare to each other, and contain no direct information about the width, shape, or peculiarities of the mass distribution.It is hence desirable that fractionation techniques, such as size exclusion chromatography (SEC), be able to provide an absolute determination of the mass distribution, from which all the mass moments can be computed, and, simultaneously, be able to measure as many useful , associated, mass-dependent properties, X(M) as possible. These latter properties may include the root mean square radius of gyration Rg (=l/2 > w here is the mean square radius of gyration), intrinsic viscosity [η], diffusion coefficient, specific conductivity, etc. Over the past fifty years a large body of theoretical and empirical knowledge has been built up concerning the physical relationship between polymer structure, dimensions, interactions and hydrodynamics, as revealed by such properties. Many

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Section: _47?n 2 {Dnldcfmentioning

confidence: 99%

Coupled Multiangle Light-Scattering and Viscosimetric Detectors for Size Exclusion Chromatography with Application to Polyelectrolyte Characterization

Reed

1996

ACS Symposium Series

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Data evaluation for unified multi‐detector size exclusion chromatography — molar mass, viscosity and radius of gyration distributions

Reed

1995

Macro Chemistry & Physics

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The output of a size exclusion chromatography (SEC) system was connected to a single capillary viscometer, a multi‐angle laser light scattering detector (MALLS) and a refractive index detector (RI). This provides absolute distributions of molar mass, radius of gyration and reduced viscosity, which are valuable both for practical polymer characterization and as tests of physical polymer theories. The instrument interfacing is described, along with the method of data analysis. A quantitative investigation of systematic and random sources of error and their influence on polymer characterization is made. An experimental example using a biopolyelectrolyte (hyaluronate), including complete error analysis, is presented, along with other data. Although the emphasis here is on aqueous SEC, most of the principles should carry over to organic phase SEC. A simultaneous, in‐line comparison of a low‐angle laser light scattering (LALLS) detector and MALLS detectors was also made. The dangers of ‘universal calibration’ for hydrosoluble polymers are also illustrated.

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The refraction correction for the Fica 50 type of light scattering photometer

1980

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The factor for the refraction correction was considered for the Fica 50 type of light scattering photometer, in which the scattered light is twice refracted before reaching the detector. The correction factor was first calculated after Hermans and Levinson, which elucidated that the factor is just the same as for the Brice type of photometer, and a vat liquid has no further effects on the final form of the correction factor. This result was examined and found to be practically applicable to a Fica 50 photometer by measuring the scattering intensities of several liquids and the RAPRA PS2 standard polystyrene in solvents of varying refractive index.

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Light scattering from cylindrical cells in the `Sofica' photometer

Cited by 5 publications

References 10 publications

Coupled Multiangle Light-Scattering and Viscosimetric Detectors for Size Exclusion Chromatography with Application to Polyelectrolyte Characterization

Coupled Multiangle Light-Scattering and Viscosimetric Detectors for Size Exclusion Chromatography with Application to Polyelectrolyte Characterization

Data evaluation for unified multi‐detector size exclusion chromatography — molar mass, viscosity and radius of gyration distributions

The refraction correction for the Fica 50 type of light scattering photometer

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