Optically active poly(phenylacetylene) film: Simultaneous change of color and helical structure

An optically active and color changeable polyphenyl acetylene film having a chiral OH group, which should form a hydrogen bond to affect the helical structure, was analyzed. The helical conformational change of this polymer in the film state was studied by circular dichroism spectroscopy. When this film was exposed to toluene vapor, the CD pattern was dramatically changed. When the film was heated at 100° C for 3 min, the color of the film turned to orange and novel novel absorption appeared around 450 nm. The results show that color and helical structured of the film were simultaneously changed in the film state by simple solvent and/or thermal treatment.