Experimental aspects of light scattering and application to polymer solutions

4 Experimental aspects of light scattering and application to polymer solutions 

Optically clean solutions, especially aqueous solutions (including pure water used as solvent), must be carefully prepared for light-scattering measurements, to be free of dust particles and other extraneous scatterers. Filtration through a membrane filter or centrifugation is widely used to clarify solutions. This concern for cleanliness also extends to glassware, especially scattering cells. 

Instrument calibration can be accomplished by using pure liquids, solutions and colloidal dispersions. Among them, pure liquids with known reduced scattering intensity / e, such as benzene, are the most commonly employed standards. Detailed procedures for filtration and calibration methods are described in ref. 27. Data on Rq of several pure liquids, such as benzene, were collected by Kratochvil et al. [34] for incident light wavelengths of 436 and 549 nm and by Pike et al. [35] for an incident light wavelength of 633 nm. 

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