Polymer, Vol.99, 447-452, 2016
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 x 10(-3) and 12.2 x 10(-3) s(-1) for the wrinkle formation. The wrinkle structures were modulated within the kapp mainly due to variation in the extent of shrinkage of the formulated prepolymer layers with the content of TEGDA. (C) 2016 Elsevier Ltd. All rights reserved.
Keywords:Wrinkle formation;UV-crosslinkable liquid prepolymers;Formulation;Photopolymerization kinetics