Polymer films structural features

The PL spectra of the PFs show well-resolved structural features with maxima at 420,445, and 475 nm assigned to the 0-0, 0-1, and 0-2 intrachain singlet transition, respectively (the 0-0 transition, the most intense) [247]. Due to the tail emission spectrum of PFs, the thin films emit bright sky-blue light. The QE of the PFs is very high, typically in the range of 40 to 80% and, as shown for PFO 196, it depends substantially on the morphology of the polymer [248]. 

Infrared Spectrum. The plasma polymerized organic film shows features distinctive from the conventional polymer. According to ESR measurements (31), the film contains a high concentration of residual free radicals, which showed a relatively long life time. The free radicals were oxidized in air and the oxidization is promoted significantly at elevated temperatures. The film is not soluble in usual solvents and it is more thermally stable than the conventional polymers. These properties are thought to be caused by the highly crosslinked structure of the film (32). 

Graphite and carbon fibers have been used at templates. Thus, nylon 6 has been polymerized on a graphite matrix. Such syntheses of polymers in the presence of a solid template, where the solid acts as a template have been described as polymerization-induced epitaxy (PIE). The monomer and resulting film is adsorbed on the template surface through only van der Waals forces. After polymerization, the polymer is washed from the template. The recovered polymer retains special structural features introduced by the template. 

While dicarboxylic acid-functional pyrroles have received only cursory attention in condensation polymerizations, other derivatives have been studied extensively. Pyrrole itself has been electrooxidatively polymerized (81CS145) to give a flexible conductive film, presumably containing poly(2,5-pyrrolediyl) units (23) as the main structural feature. The blue-black polymer obviously contains other functionality, as evidenced by elemental analysis and by the fact that it carries a partial positive charge, and it exhibits p-type conductivities approaching the metallic range (e.g. 100 fi-1 cm-1). The main utility of poly(pyrrole) (23) has been for the modification of electrode surfaces, although numerous other applications can be envisioned. 

Structural Features and Structure - Property Relationships of Thin Polymer Films... 

For ionomer samples with low ion. content (less than 5 mol %), only crazes are formed. Figure 24 shows a typical TEM picture of a craze in a deformed thin film of an ionomer with low ion content. This can be compared with the craze structure of starting PS (Fig. 12b). Also, in Fig. 25 two views of the craze microstructure in PS (Fig. 25a and b) are compared with corresponding views (Fig. 25c and d) of the craze structure of the ionomer containing 4.8 mol % ion content. These micrographs show typical structural features of crazes of glassy polymers a) a midrib of lower fibril... 

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