Fig. 1: Overview of orthogonal photocontrol system.
From: Active light-controlled frontal ring-opening metathesis polymerization
a ROMP with DCPD showing metallacyclobutane intermediate, ring-opening of the cyclopentene is not shown, b photoactivation of NPPOC-TMG, for inhibition of FROMP and c the photosensitizer system for wavelength orthogonal acceleration of FROMP. d Schematic of a 2-channel experiment to compare front velocities with a test and control (unirradiated) channel. e Still images of FROMP with photoinhibition in a 2-channel mold. The right channel is unirradiated and propagates to the end of the channel. The left channel is preirradiated with 30 mW cm−2 light for 180 s and front propagation is arrested on entering the inhibited region. The resin contains 8 mole equivalents of NPPOC-TMG:catalyst and a thermochromic dye to enhance visualization of the front. For scale, the molds have triangular indents spaced 5 mm apart along the edges.
