Polymers green-colored

DPA) main chain of 44 is highly emissive in a green color. Polymers from disubstituted acetylenes are usually resistant to thermolysis. Some of them, however, are sensitive to photooxidation, which quenches their photoluminescence. For example, UV irradiation of a film of 45 in air through a mask quenches the luminescence of the exposed region, while the unexposed area remains emissive in a blue color. A photoluminescence image is thus directly drawn without a developing process. 

At x=l, the redox reaction was very slow and the UV-VIS absorption showed no change with time. The orange - yellowish color persisted for weeks, indicating that there was little or no reduction (i.e., poor conversion) of Cr(VI). At x=4 or more, development gf blue color occurred instantly, which is evidence of CrCHgOJg production via the acidic redox mechanism. At x=2 to 3, the green color of dated Cr(III) developed in minutes, followed by gelation of the polymer. 

No deep-green colors are available in this family of PTs, mostly due to the broadness of the emission spectra. Some absorption and emission data of these polymers are collected in Table 13. 

Mecerreyes et al. [91] used ionic liquid-supported HRP in water to conduct enzyme-catalyzed free radical polymerization. In this reaction procedure, the HRP was immobilized in BMIM NTf2 by simple dissolution. This was then added to an aqueous solution of aniline, dodecylbenzenesulfonic acid (DBSA) and H202 at pH 4.3. Under these conditions, polymerization occurred immediately (as evidenced by the green color of the solution), but yield was low due to precipitation and association of polyaniline at the surface of the ionic liquid. To overcome this problem, a less hydrophobic ionic liquid, BMIM PF6 was used. In this case, the solution separated into two liquid phases after 0.5 hours one contained the polymer in water and the other was ionic liquid-immobilized HRP. The IL-HRP could be recycled and polymerization successfully repeated up to five times. The resulting polymer had similar electric conductivity properties to conventionally prepared polymer. A schematic of this process is presented in Figure 13.10. 

In Fig. 97, the nanostructures in the polymer are shown. Three lines are visible, which have a width of approximately 25 nm and a length of 200-300 nm. The mechanical nature of the structuring is clearly visible by the walls at the end of the structured line (lower part of the line, green color). 

Pyrrole and N-methylpyrrole were reported to form blue to-blue-green colored insoluble polymers on condensation with squaric acid [7]. However, their absorption and conduction properties have not been investigated. 

Films of colored polymers were obtained by disassembling floppy diskettes, ABS, of different colors and using segments of the 0.25-mm-thick walls. Red, orange, yellow, green, and blue pieces were examined with thicknesses of 0.25 and 0.5 mm (two layers). 

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