Determined by laser light scatter

The molecular weight and its distribution have been determined by laser light scattering, employing a new apparatus for ETFE dissolution and solution clarification at high temperature diisobutyl adipate is the solvent at 240°C. The molecular weight of molten ETEE is determined by high temperature rheometry (21). 

Figure 8. Molecular weight distribution of branched PVAc (B...) as determined by laser light scattering (LLS) and size exclusion chromatography (SEC)/viscometry. A comparison of results by the two methods is listed in Table 2.

Fig. 9.1. Synthetic microbubble histograms determined by laser-light scattering in aqueous media (at 21°C) (A) saturated solution of Filmix 3 surfactant mixture (B) distilled water alone (C ) computed difference in above two histograms. (See text for further discussion.)...

Figure 7. Particle nucleation and growth kinetics determined by laser light scattering Rayleigh ratio vs. time. Exp. 1 no surfactant present Exp. 2 (SDS) = 6 X 10 4 mol dm 3. Theor Calculated from Curve 4, Figure 5, considering particle growth by polymerization.

Volumetric (volume of microbeads in each diameter class) and cumulative size distributions were determined by laser light scattering, with a 2602-LC particle analyzer (Malverin Instruments) according to the lognormal distribution model. The mean diameter and the arithmetic standard deviation were calculated from the cumulative distribution curve [22]. 

Determination of Vesicle Size by Laser Light Scattering... 

Recently, Siu et al. [139] studied the effect of comonomer composition on the formation of the mesoglobular phase of amphiphilic copolymer chains in dilute solutions. The copolymer used was made of monomers, N,N-diethylacrylamide (DEA) and N,N-dimethylacrylamide (DMA). like PNI-PAM, PDEA is also a thermally sensitive polymer with a similar LCST, but PDMA remains water-soluble in the temperature range (< 60 °C) studied. At room temperature, copolymers made of DMA and DEA are hydrophilic, but become amphiphilic at temperatures higher than 32 °C. Before the association study, each P(DEA-co-DMA) copolymer was characterized by laser light scattering to determine its weight average molar mass (Mw) and its chain size ( Rg) and (R )). The copolymer solutions (6.0 x 10 A g/mL) were clarified with a 0.45 xm Millipore Millex-LCR filter to remove dust before the LLS measurement. 

C. Determination of Microbead Size Distribution by Laser Light Scattering. . . 874... 

A particle size analyzer determines the particle size distribution of powders either dry or dispersed in solvent by laser light scattering based on the Fraunhofer scattering theory. This type of equipment has an optical bench whose combined dynamic range is nominally 0.7-2000 pm. The instrument calculates mean diameters and distribution data. An interfaced computer generates sample histograms. This technique has been applied to the study of particle size and particle size distributions for polymer powders and polymer suspensions in a variety of solvents. 

Example 11.2 ] Determining the molar mass and size of a protein by laser light scattering... 

Particle size and zeta potential measurements The particle size and particle size distribution were determined by dynamic light scattering (DLS) using Zetasizer 3000HSA instrument (Malvern, UK) at a fixed angle of 90° and laser wavelength of... 

Wellons, J. D., and Gollob, L., Determining Mo- 77. lecular Weight of Phenolic Resins by Laser Light-Scattering, in Phenolic Resins Chemistry and 78. Application, Tacoma, WA, Weyerhaeuser Co.,... 

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