Photochemically‐induced refractive index and fluoresence patterning on polymer films

Abstract

The molecular design for large photo‐induced refractive index changes in transparent visible light region was proposed and realized with norbornadiene polymers and poly(vinyl cinnamate). The patterning of pure refractive‐index contract on their transparent films was made with near‐field scanning optical microscopy (NSOM). Reversible fluorescence patterning on polymer films is also presented by using controlled energy transfer from a fluorescent pyromethene to a photochromic diarylethene.

Photoresponsive polyamides containing pentamethylated norbornadiene moieties: Synthesis and photochemical properties under sunlight irradiation

“…In addition to conversion and storage of solar energy, the photochemical isomerization of NBD has been studied as a new alternative in the field of optoelectronics (memory, optical switches and other devices), as a photochromic system with potential application in the data storage technology, and as an energetic binder for solid rocket propellants . NBD structures are generally introduced into polymer chains as pendant moieties by postpolymerization chemical modification, by radical or cationic polymerizations of NBD‐containing vinyl monomers, or by ring‐opening copolymerization of glycidyl esters containing NBD moieties with various carboxylic anhydrides . Besides, the synthesis of polyamides containing NBD structure in the backbone by direct or catalyst transfer polycondensation has been reported earlier …”

“…Solutions previously reported to drive this photochemical process using higher wavelength irradiation sources and to improve the quantum yield include: the addition of sensitizers and chromophores, the conjugation of electron withdrawing substituents to the NBD moiety, and the use of NBD‐containing metal complex catalysts . In addition to conversion and storage of solar energy, the photochemical isomerization of NBD has been studied as a new alternative in the field of optoelectronics (memory, optical switches and other devices), as a photochromic system with potential application in the data storage technology, and as an energetic binder for solid rocket propellants . NBD structures are generally introduced into polymer chains as pendant moieties by postpolymerization chemical modification, by radical or cationic polymerizations of NBD‐containing vinyl monomers, or by ring‐opening copolymerization of glycidyl esters containing NBD moieties with various carboxylic anhydrides .…”

Selective [2 + 2]-Cycloaddition in Methacrylic Stilbene Polymers without Interference from E/Z-Isomerization

“…R f : 0.27 (3:1 pentane:diethyl ether). 1 (16), 181 (14), 167 (12), 152 (9), 141 (8), 113 (6), 86 (36), 69 (92), 41 (52). HRMS (EI): calcd for C 20 H 20 O 4 (M + ), 324.1362; found, 324.1369.…”

“…6 In general there are two types of refractive index change materials; refractionincrease materials 7,8 and refraction-decrease materials. 9,10 Typical values for refractive index changes are in the range of Δn 0.001À0.1. 1 Light sensitive compounds may be coumarins, 11 cinnamic acids, 12 stilbenes, 13 chalcones, 14 and others.…”

Imaging by Sensitized Oxygenations of Photochromic Anthracene Films: Examination of Effects That Improve Performance and Reversibility

“…[4] The changes of molecular properties may include, for example, their absorption spectra, dipole moment, or refractive index. [5,6] A vast contribution to research on photochromic materials deals with the families of diarylethenes and fulgides, characterized by photochemically allowed cyclization and ring-opening processes. [7,8] They exhibit both a striking resistance to fatigue and a thermal irreversibility.…”