Chemistry Letters, Vol.50, No.1, 84-86, 2021
Stepwise Assembly of Ultrathin Poly(vinyl alcohol) Films on Photoresponsive Diarylethene Crystals
Rodlike two-component mixed crystals composed of 1-(5-methyl-2-phenyl-4-thiazolyl)-2-(5-methyl-2-p-tolyl-4-thiazolyl)perfluorocyclopentene (1a) and 1,2-bis(5-methyl-2-p-tolyl-4-thiazolyl)perfluorocyclopentene (2a) undergo light-driven bending upon alternate irradiation with ultraviolet (UV) and visible light. To provide stability of the crystals in organic solvents, the crystal surface was coated with ultrathin poly(vinyl alcohol) (PVA) films using a stepwise assembly method. The crystals coated with 15 ultrathin PVA layers were stable in n-hexane and no appreciable suppression in the bending performance was observed by the PVA coating. The light-driven bending could be repeated more than 1000 times.