Photochromic polymeric systems

G. Smets, Photochromic behavior of polymeric systems and related phenomena, PureAppl. Chem. 30,1-24(1972). 

We shall now embark on the main focus of this chapter photochromic azobenzene polymers and photochromic materials capable of undergoing photodimerization for potential use in optical data storage applications. Herein, the photochromic polymers described are those in which the photochromic molecule is covalently linked, either as part of the main chain or as a side-chain, to the polymeric system. 

Stephenson, Kirks, and Scranton tried to develop a working model of photoinitiation of thick polymeric systems. They used the generalized governing equations for photochromic illumination. The equations they derived are as follows... 

There are three polymeric systems appropriate for holography photopolymeriz-able systems photochromic systems and photorefractive systems (Table 3.34). Detailed information on the topic of polymers in holography is available in various reviews [313-320]. 

Various photochromic systems employing polymeric thin films or LB... 

Monolayers (2D films) can be regarded as ultimate thin states of organic and polymeric materials and are quite fascinating for constructing molecular amplification systems for the following reasons. First, the simplest (thinnest) structure of a monolayer allows one to comprehend the details of molecular communications and motions, because the excessive complexities of three-dimensional materials are efficiently excluded. This can lead to many implications on the material design of wide varieties of related systems. Second, for surface-mediated transfer processes, which consist of molecule-to-molecule transfer of information based on molecular orientations inscribed on uppermost surface layers, the existence of monolayers on material surfaces is sufficient for performances of macroscale controls of materials. Note that the nature and behavior of buried photochromic moieties in thicker films play minor roles. 

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