Induction of Polyacetylene to a Chiral Smectic Liquid Crystal-Chiral Direct Conversion.

The synthesis of polyacetylene-bearing pyrimidine-type three-ringed mesogenic core exhibiting smectic C (SmC) characteristics was conducted. Gas-phase iodine doping of the polymer provided evidence of chemical interaction between the polyene and iodine, which acted as an electron acceptor. The side-chain fluorine atom tilted the mesogen moiety to form SmC as a tilted liquid crystal. The addition of a small amount of chiral inducer yielded SmC* of the polymer as the chiral version of SmC. The liquid crystallinity and electronic properties of the π-conjugated chiral liquid crystal polymer with a helical structure were evaluated.

Synthesis of Polyaniline/Scarlet 3R as a Conductive Polymer.

Polyaniline (PANI) was prepared in the presence of the acidic dye scarlet 3R. Color tuning was performed on PANI through doping-dedoping processes and by changing the solvent used during the optical absorption spectroscopic measurements. The chemical structure of the resulting polymer-dye composite was analyzed using infrared absorption spectroscopy, and it showed the occurrence of secondary doping in m-cresol. The shape of the UV-Vis optical absorption spectra for the composite solution is dependent on the types of organic solvents used during the analysis, which was influenced by the conformation of PANI and the ionic interactions between PANI and scarlet 3R.

Synthesis of Polyaniline in Seawater.

To date, polyaniline (PANI) has been synthesized in pure water. Aside from this, the application of PANI as a conducting polymer could be extended if it can be effectively synthesized in seawater, which constitutes 70% of the surface of the Earth. The production of functional plastics using natural resources without any additional purification would improve industrial production and enhance the comfort associated with our daily life. However, no examples of the effective application of seawater to PANI synthesis have been reported. Herein, PANI with an electrical conductivity of ~10-2 S/cm was synthesized in seawater as the reaction solvent. The electron spin resonance measurements confirmed the role of the polarons of PANI as charge carriers. In addition, a PANI/silk composite was prepared in seawater to produce a conducting cloth for further applications. The performance of the PANI prepared in seawater as the solvent was comparable to that of the PANI prepared in pure water. Thus, the proposed method allowed for the production of the conducting polymer via a convenient and low-cost method. This is the first study to report the usage of seawater as an abundant natural resource for synthesizing conducting polymers, promoting their wide application.