Confinement of Photopolymerization and Solidification with Radiation Pressure
journal contributionposted on 2011-09-21, 00:00 authored by Syoji Ito, Yoshito Tanaka, Hiroyuki Yoshikawa, Yukihide Ishibashi, Hiroshi Miyasaka, Hiroshi Masuhara
Controlling chemical reactions within a small space is a significant issue in chemistry, and methods to induce reactions within a desired position have various potential applications. Here we demonstrate localized, efficient photopolymerization by radiation pressure. We induced a one-photon UV polymerization of liquid acrylate solutions in the optical-trapping potential of a focused near-IR (NIR) laser beam, leading to the confinement of solidification to a minute space with dimensions smaller or equal to one-fifth of the wavelength of the NIR laser. Our approach can produce solidification volumes smaller than those achievable with conventional one-photon polymerization, thus enabling the production of tiny polymeric structures that are smaller than the diffraction limit of the trapping light. This is the first demonstration of a radiation pressure effect on a photochemical reaction.