Latex surface coverage

FIG. 17 Plot of normalized surface coverage C of self-assembled layer of particles Ic vs. dipping time of substrate for different concentrations of the latex dispersion (T = 23.5°C, pH = 5.8). 

The viscoelastic behavior of concentrated (20% w/w)aqueous polystryene latex dispersions (particle radius 92nm), in the presence of physically adsorbed poly(vinyl alcohol), has been investigated as a function of surface coverage by the polymer using creep measurements. From the creep curves both the instantaneous shear modulus, G0, and residual viscosity, nQ, were calculated. 

Flocculation experiments were also performed with half of the latex pretreated with polymer to ensure complete surface coverage. Coagulation rates were determined using aluminum chloride at pH 3. 

Latex Seed Particle Growth at High Surfactant Surface Coverage... 

The surface area per gram occupied by Siponate DS-10 and Triton X-100 were measured to allow the calculation of surfactant surface coverage on the seed latexes. The experimental procedure and analysis were based on Maron s technique (17,18). The procedure utilized is explained in detail below. 

Fig. 4. a Polystyrene particle size vs amount of SDS (KPS as initiator) b Surface tension of the latexes and coverage of the particles in dependence of particle size... 

In view of the problems involved with the particle size measurement of soft particles by electron microscopy and the uncertainty In surface coverage by oleate soap molecules which were discussed in the introduction, agreement between the V/S average electron microscope measurements and polymerization rate measurements for these latexes Is quite acceptable. 

Latex, aggregation 52 -, charged 51 -, monodisperse 47 -, ordered packing 53 -, seed 49 surface coverage 47 Liquid crystalline polymers 3... 

We have measured A gH for plateau adsorption of HPA on different substrates (11,26,33) and for RNase on polystyrene (33) With both proteins, and under many conditions, A gH > 0, implying again that spontaneous adsorption occurs by virtue of an entropy increase A gS > 0. In section 2 the same conclusion has been drawn for the interaction between HPA and polystyrene latex at low surface coverage. 

Fig. S.9. The dependence of the CFV and LCFT upon stabilizer surface coverage for poly(12-hydroxystearic acid) stabilized latex particles in n-heptane (after Napper, 1968b).

Fig. 5.10. The dependence of the UCFT of polyfoxyethylene) stabilized latex partidtes u stabilizer surface coverage in 0-39 M MgS04 (after Napper, 1970a).

Adams, et al. [89] could find no evidence of differing efficiency of entry between charged and uncharged radicals or of any effect of the extent of surface coverage with emulsifier or of ionic strength collisional or diffusive entry models predicted entry rate coefficients which were too large. Subsequently Maxwell, et al. [60] concluded that the rate-determining process was the time required for an initiator radical to add two styrene residues in the aqueous phase and thereby acquire sufficient hydrophobic character to adsorb onto a latex particle. 

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