Polydiacetylene (PDA) polymers show the blue PDAs with 640 nm maximum absorption wavelength, which can display a unique color change to a red with 550 nm maximum absorption wavelength upon environmental stimulation. In addition, red-phase PDAs are fluorescent even though blue-phase PDAs are nonfluorescent, which enables PDAs to be not only colorimetric sensors but also fluorescent sensors. Common stimulations or anayltes have been temperature, pH, metal ions, anions, surfactants, other biologically important molecules, etc.
Typically, PDA polymers have been prepared by UV irradiation from self-assembled diacetylene (DA) monomers. Interestingly, it has not been reported that PDAs have been obtained from plasma induced polymerization process so far. However, it should be noticed that since some new types of DAs (diacetylene monomers) would not be appropriate to produce PDA by UV irradiation due to the structural differences of head groups of DA monomers, alternative routes could be carefully considered. For example, a new diacetylene (DA) monomer bearing hexaethylene glycol (HEG) units in this study did not undergo into blue PDAs under UV radiation in both the solution state and embedded fiber. On the other hand, we found out that it was easily polymerized to produce PDAs in the form of pure HEG embedded fibers as well as the mixture fibers between HEG and 10, 12-pentacosadiynoic acid PCDA at even very short exposure of plasma for the first time.
S. Lee, Y. Cho, B. U. Ye, J. M. Baik, M. H. Kim, J. Yoon Chem. Commun. 2014, DOI: 10.1039/C4CC03511A
S. Lee, J. Lee, M. Lee, Y. K. Cho, J. Baek, J. Kim, S. Park, M. H. Kim, R. Chang, J. Yoon Adv. Funct. Mater. 2014, 24, 3699-3705.