Wrinkle structures formed by formulating UV-crosslinkable liquid prepolymers

Artificial wrinkles have recently been in the spotlight due to their potential use in high-tech applications. A spontaneously wrinkled film can be fabricated from UV-crosslinkable liquid prepolymers. Here, we controlled the wrinkle formation by simply formulating two UV-crosslinkable liquid prepolymers, tetraethylene glycol bis(4-ethenyl-2,3,5,6-tetrafluorophenyl) ether (TEGDSt) and tetraethylene glycol diacrylate (TEGDA). The wrinkles were formed from the TEGDSt/TEGDA formulated prepolymer layers containing up to 30 wt% of TEGDA. The wrinkle formation depended upon the rate of photo-crosslinking reaction of the formulated prepolymers. The first order apparent rate constant, k app , was between ca. 5.7 × 10 −3 and 12.2 × 10 −3 s −1 for the wrinkle formation. The wrinkle structures were modulated within the k app mainly due to variation in the extent of shrinkage of the formulated prepolymer layers with the content of TEGDA.