Three topics relating to potential applications of spiropyran--merocyanine systems in memories and switches--are examined: the formation of organized structures whose optical properties can be ...affected by an electric field, the nonlinear optical properties of the photochromic systems and real-time holography.
Photochromes, bound to polysulfone via carboxyamide bonds and physically blended in a polymeric matrix, were prepared and their physical and photochromic properties investigated. In order to express ...the photochromic activity, plasticization is required; this is readily achieved by using the swelling solvent, N-methylpyrrolidone (NMP). The photochromic activity is repressed in the presence of carboxylic groups, and this requires complex blocking of any acidity, e.g., by esterification or amidation. The photochromic activity was expressed in membranes made from functional and blended polysulfones, yet the photoresponsive membranes did not produce a significant electroresponse or, if they did, this decayed rapidly. Obviously, membranes with a much higher degree of covalent binding are needed.
Photocontraction of Liquid Spiropyran-Merocyanine Films Cabrera, Ivan; Shvartsman, Felix; Veinberg, Olga ...
Science (American Association for the Advancement of Science),
1984-Oct-19, Letnik:
226, Številka:
4672
Journal Article
Recenzirano
Amorphous films of a photochromic spiropyran containing a mesogenic group melt, when exposed to heat together with irradiation, to yield a red fluid. This fluid contains aggregates of merocyanine ...molecules and exhibits marked contraction under light illumination. The mechanism of the photocontraction is dependent upon a specialized microstructure, which may be termed a ``quasi-liquid.''
