POLY DIACETYLENES AS PROCESSIBLE CPs

Poly(diacetylenes) (P(DiAc)) have the general formula 

More recent work [263-265] however has shown that certain long-chain substituents render P(DiAc) s substantially soluble, in their de-doped form of course, in common organic solvents such as THF and toluene. Table 8-1 below lists some side groups (R,R in the above formula) yielding such soluble P(DiAc) s. Once in solution, these can then be processed in the conventional manner, e.g. cast as films which are subsequently doped with I2 vapor. Handling under inert atmosphere is however a strong recommendation for producing stable doped P(DiAc) s. 

TABLE 8-1 SUBSTITUENTS, (R,R ) IN P(DiAc) s SOLUBLE IN THEIR DE-DOPED FORMS. 

It is evident that the use of solubilizing groups, such as the long alkyl chains for poly(thiophenes) or the long chain substituents for the P(DiAc) s described above, can render some measure of solubility or melt processibility to CPs. Indeed in one such example, Liu and Gregory [266] describe the chemical polymerization of a 3-urethane-substituted thiophene, to yield a P(T) soluble, albeit only in its de-doped 

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