Polystyrene lattices stability

Some typical transmission electron micrographs of these polystyrene lattices are shown (Sample 2 and Sample 3) in Figure 10.6. The effects ofthe amount of stabilizer S is the relative amount of stabilizer) on the particle size is strong the more stabilizer applied, the smaller the particles are. It must be emphasized that this effective stabilization of nanopowders by our fluorinated block copolymers is not restricted to polymerization processes, but can be generalized to the fabrication of all organic nanopowders in media with low cohesion energy density, e.g., to the dispersion of dyes, explosives, or drugs. 

Measurements of heterocoagulation can be made in much the same way as were measurements for the addition of an electrolyte to a latex. For example, with an appropriate mixing device (Cheung, 1979) an anionic latex can be added to a cationic one and the progress followed by turbidity measurements to obtain a stability ratio. Results of this type are shown m Fig. 24 in the form of log W against Af /(Af+ + N ) where N+ and are the number concentrations of the cationic and anionic lattices respectively. The anionic latex used was composed of polystyrene particles (diameter... 

To be sure, the figure depicts the structures observed for polystyrene-6Zocfc-polyisoprene, but these are quite typical. Spherical, cylindrical and layer-like domains are generally observed in all block copolymers. Less is known about how general special types like the OBDD lattices are. Observations are rare, since these exist in small regions only, positioned in-between the extended stability ranges of the major structures. 

Abstract These test methods cover the synthetic rubber lattices ABR, BR, CR, HR, NBR, NCR, NIR, PBR, PSBR, SBR, SCR, SIR, synthetic rubber lattices with substituted carboxylic acid groups on the polymer chain, and reinforced synthetic mbber lattices. Covered tests include the procedure for collecting samples and determining total solid content, volatile unsaturates content, pH, surface tension, viscosity, coagulum, bound styrene, Mooney viscosity, mechanical stability, polystyrene reinforcement in contained polymer, and residual acrylonitrile content. Each test method contains information on material exceptions, apparatus, and test procedures. 

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