High surface area polymers

Zhou, Z., Dominey, R. N., Rolland, J. R, Maynor, B. W., Pandya, A. A. and DeSimone, J. M. 2006. Molded, high surface area polymer electrolyte membranes from cured liquid precursors. Journal of the American Chemical Society 128 12963-12972. 

Pore Size. All other factors being equal, the pore size is inversely proportional to the surface area. For high-surface-area polymers, problems begin when the molecular diameters of the solutes and the pore diameters become comparable so that passage of the solutes through the pores is severely restricted. These comparable diameters... 

High-surface-area polymers can be used to accumulate large amounts of relatively insoluble organic compounds from very large volumes of water. In the adsorption step of the accumulation, the more soluble components are not recovered efficiently so that the accumulated solutes do not accurately reflect the proportions of different compounds present at trace levels in the water. Nevertheless, the very simple polymer approach can be used for many studies because the mutagenicity appears to reside in the hydrophobic fraction that the polymers accumulate efficiently. This conclusion is based on favorable bioassay comparison of the extracts accumulated by the XAD-2 method and the extracts collected by the more complicated and expensive freeze concentration method (216, 233). 

Synthesis and characterisation of high surface area polymers... 

Gow, A.S., and Phillips, J., Calorimetric-study of oxygen adsorption on a high surface area polymer-derived carbon. Energy Fuels, 6(2), 184-188 (1992). 

In the field of materials synthesis, T8[CH = CH2]8 has been used to prepare three-dimensional (meso)porous polymers with high surface area via reactions with TgHg or T8[OSiMe2H]8 in the presence of a Pt catalyst as described in Section Xu et al. prepared a POSS-based monomer by reaction... 

Figure 1 shows the results of those experiments. It is important to recognize that in this experiment the polymer was present in a form affording high surface area when compared to other studies where rods, pellets, plates, fibers, and so forth were used. It is often quite difficult to compare exact degradation times from various independent studies due to differences in implant surface area and... 

The next two examples illustrate more complex surface reaction chemistry that brings about the covalent immobilization of bioactive species such as enzymes and catecholamines. Poly [bis (phenoxy)-phosphazene] (compound 1 ) can be used to coat particles of porous alumina with a high-surface-area film of the polymer (23). A scanning electron micrograph of the surface of a coated particle is shown in Fig. 3. The polymer surface is then nitrated and the arylnitro groups reduced to arylamino units. These then provided reactive sites for the immobilization of enzymes, as shown in Scheme III. 

We have already referred to the Mo/Ru/S Chevrel phases and related catalysts which have long been under investigation for their oxygen reduction properties. Reeve et al. [19] evaluated the methanol tolerance, along with oxygen reduction activity, of a range of transition metal sulfide electrocatalysts, in a liquid-feed solid-polymer-electrolyte DMFC. The catalysts were prepared in high surface area by direct synthesis onto various surface-functionalized carbon blacks. The intrinsic... 

Dendrimer-protected colloids are capable of adsorbing carbon monoxide while suspended in solution, but upon removal from solution and support on a high surface area metal oxide, CO adsorption was nil presumably due to the collapse of the dendrimer [25]. It is proposed that a similar phenomena occurs on PVP-protected Pt colloids because removal of solvent molecules from the void space in between polymer chains most likely causes them to collapse on each other. Titration of the exposed surface area of colloid solution PVP-protected platinum nanoparticles demonstrated 50% of the total metal surface area was available for reaction, and this exposed area was present as... 

Biocides are naturally toxic to lower organisms and therefore must be handled with care. Strict government rules control the sale and use of biocides, especially those used in food contact applications. They are added at the fabrication stage. The morphology of the polymer article is important, e.g., high surface area articles, such as foams, biodegrade more rapidly. 

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