Polymer backbone phosphorous

A side reaction involving incorporation of the phosphorus moiety into the polymer backbone is unlikely to occur because no phosphoric acid has been detected upon oxidation of the polymer with a mixture of sulfuric acid and nitric acid. 

Zhang, K., Chen, Z., Zou, Y, Gong, S., Yang, C., Qin, J., Cao,Y., 2009. Effective suppression of intra- and interchain triplet energy transfer to polymer backbone from the attached phosphor for efficient polymeric electrophosphorescence. Chem. Mater. 21,3306-3314. 

Many different types of fuel-cell membranes are currently in use in, e.g., solid-oxide fuel cells (SOFCs), molten-carbonate fuel cells (MCFCs), alkaline fuel eells (AFCs), phosphoric-acid fuel cells (PAFCs), and polymer-electrolyte membrane fuel cells (PEMFCs). One of the most widely used polymers in PEMFCs is Nalion, which is basically a fluorinated teflon-like hydrophobic polymer backbone with sulfonated hydrophilic side chains." Nafion and related sulfonic-add based polymers have the disadvantage that the polymer-conductivity is based on the presence of water and, thus, the operating temperature is limited to a temperature range of 80-100 °C. This constraint makes the water (and temperature) management of the fuel cell critical for its performance. Many computational studies and reviews have recently been pubhshed," and new types of polymers are proposed at any time, e.g. sulfonated aromatic polyarylenes," to meet these drawbacks. 

Polymeric dyes were prepared by coupling the p-positions of the N-aryl groups of the polymer backbones with variously substituted diarylketones using phosphorous oxychloride as an acid catalyst. The absorption of the polymeric dyes vary consideiably... 

Hybrid systems of acrylics with other technologies have been reported. Aciylic and epoxy polymers can be coupled through the use of 2-methacryloloxyethyl phosphate. The phosphoric acid functionality reacts with epoxy and the methacrylate group copolymerizes with the acrylic backbone [ 145] (Scheme 14). 

The final class of polymers containing carboranyl units to be mentioned here is the polyphosphazenes. These polymers comprise a backbone of alternating phosphorous and nitrogen atoms with a high degree of torsional mobility that accounts for their low glass-transition temperatures (-60°C to -80°C). The introduction of phenyl-carboranyl units into a polyphosphazene polymer results in a substantial improvement in their overall thermal stability. This is believed to be due to the steric hindrance offered by the phenyl-carborane functionality that inhibits coil formation, thereby retarding the preferred thermodynamic pathway of cyclic compound formation (see scheme 12). 

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