Polystyrene latex beads diameter

The first study utilizing this method was reported by Schuller in 1966 [65]. Schuller used polystyrene latex beads that were spread on a salt-containing aqueous subphase in order to keep the particles at the interface. tt-A plots of the floating particles were determined, which showed several phase regions with reproducible transition points. The author determined the particle diameters from the A-value, at which a steep rise in the isotherm occurred. Moreover, Schuller also spread millimeter-sized Styropor particles and found isotherms of similar shape [66]. By taking pictures at different surface pressure, he was able to correlate the shape with different states of order in the monolayer. Shortly after that. 

Narrow particle fractions approaching a monodisperse distribution are particularly easy to treat and characterize when the above equations are applied to experimental data. Figure 2 shows an example of the elution profile (fractogram) obtained by running a mixture of four samples of "monodisperse" polystyrene latex beads. It is clear from the figure that a rather precise value of retention volume Vr can be identified with each bead size. With Vr known, it is easy to obtain R and X from Equation 5 and thence particle diameter d from Equation 4. This operation, as noted, yields diameters accurate to approximately 1-3%. 

Figure 8.6. Separation of polystyrene latex beads of four different diameters (indicated in the figure) by a disc centrifuge operated at 3586 rpm. (From ref. 44. Reprinted with permission from R. M. Holsworth, T. Provder, and J. J. Stansbrey, in T. Provder, Ed., Particle Size Distribution, ACS Symposium Series No. 332, American Chemical Society, Washington, DC, 1987, Chapter 13. Copyright 1987 American Chemical Society.)...

Figure 9.9. Separation of polystyrene latex beads of indicated diameters in the colloidal size range by SdFFF programmed from 1500 to 75rpm at 2mL/min flowrate. (Courtesy of Bhajendra N. Barman, FFFractionation. Inc.)...

As model samples for the verification of the conventional SdFFF as a concentration methodology monodisperse polystyrene latex beads (Dow Chemical Co.) with nominal diameters of 0.357 fum (PSl) and 0.481 /Ltm (PS2) were used. They were either used as dispersions containing 10% solids or diluted with the carrier solution (triple-distilled water -r 0.1% (v/v) detergent FL-70 from Fisher Scientific Co. -l- 0.02% (w/w) NaNj) to study sample dilution effects. Diluted samples in which the amount of the polystyrene was held constant (1 /u-L of the 10% solids) while the volume in which it was contained was varied over a 50,000-fold range (from 1 to 50 mL of carrier solution) were introduced into the SdFFF column. During the feeding step, the flow rate was 5.8 mL/h for the PSl polystyrene, and 7.6 mL/h for the polystyrene PS2, and the channel was rotated at 1800 rpm for the PSl sample and at 1400 rpm for the PS2 sample. In the sep-I aration (elution) step, the experimental conditions for the two samples were as follows ... 

Fig. 1 Fractograms of the polystyrene latex beads of 0.357 /xm (PSl) obtained by the direct injection of 1 julL of PSl (a) and by the concentration procedure of the PSl sample diluted in 10 mL of the carrier solution (b) using the conventional SdFFF technique, as well as of the a-Fe203 sample with nominal particle diameter of 0.271 tm diluted in 6 mL of the carrier solution obtained by the PBSdFFF concentration methodology (Ic).

As model samples for the verification of the conventional SdFFF as a concentration methodology monodisperse polystyrene latex beads (Dow Chemical Co.) with nominal diameters of 0.357 pm (PSl) and 0.481 pm (PS2) were used. They were either used as dispersions containing 10% solids or diluted with the carrier solution [triple-distilled... 

Dalargin (10 to 10" M) stimulated the luminol-dependent chemiluminescence of mouse whole blood during phagocytosis of polystyrene latex beads (0.8 [im in diameter) recorded over 10 s (Ro-govine and Mushtakova 1995). 

Polystyrene Latex (PSL) Bead Solution Filtration Experiments were conducted to obtain filter retention, flow rate, and Ap data for a DI water based PSL bead mix solution prepared using particles ranging from bead diameters of 0.772 to 20 pm. It is a common practice to use PSL bead challenge solutions (created by mixing different size PSL bead standards in specific volumetric ratio to simulate slurry-like particle size distribution for the bead mix solution) to obtain relative quantitative retention data for various filters. These solutions are expected to retain stable PSD and provide more consistent information compared to real CMP slurries, which may change particle characteristics over time. 

The corresponding AminoPac PA-1 latex anion exchanger consists of a polystyrene/ divinylbenzene substrate with a particle diameter of 10 pm. The synthesis of the latex beads is carried out, however, using dimethylamine instead of divinylbenzene for crosslinking the polymer. Until now, no methods have been available for the separation... 

Polystyrene latex (PSL) beads of two different sizes were used as 0.1 wt.% sample solution in this study. The nominal diameters of them are 269 7 nm (NBS 1691) and 305 nm ( 8.4 nm standard deviation, Seragen Diagnostics Inc.). The density of the both latexes were taken to be 1050 g m 3. 

Latex-based anion exchangers are comprised of a surface-sulfonated polystyrene/divi-nylbenzene substrate with particle diameters between 5 pm and 25 pm and fully animated porous polymer beads of high capacity, which are called latex particles. The latter have a much smaller diameter (about 0.1 pm) and are agglomerated to the surface by both electrostatic and van-der-Waals interactions. A scanning electron micrograph of this material is shown in Fig. 3-12. Hence, the stationary phase features three chemically distinct regions ... 

A polymer called latex , prepared from a monomer that contains organic groups, is deposited as an array of tiny beads (0.1-0.2 ptm in diameter) on an waterproof support to form a continuous film-like layer about 1-2 gum thickness. The support is made of micro-spheres of silica or glass or polystyrene of about 25 gum diameter (Figure 4.6) This gives rapid equilibriums between stationary and mobile phases. 

The deposition of latex particles on the cationic resin beads is almost certain to occur, but the amount of latex polymer lost in this way is likely to be small. For example, a monolayer of polystyrene particles deposited on the surface of 1 g of 0.5mm-diameter cationic resin beads amounts to 1.3, 0.47, and 0.24 mg for particle sizes of 1760A, 640X, and 330X, respectively. From the proportions of latex and ion-exchange resin used in these experiments, this corresponds at most to about 1% of the latex polymer. Of course, the particles may deposit to form more than one layer, but the number of layers that can be formed by this mechanism is limited moreover, the formation of several such layers would remove only a minor pro-... 

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