The photochemical and thermal cis to trans isomerization of aromatic azo groups covalently bonded within polymers and its practical consequences as well as some other recent applications are reviewed. The kinetics and mechanism of the isomerization of azo polymers are briefly presented and then several recent developments in azo polymers research are discussed. They include liquid crystallinity, nonlinear optical properties, monolayer assemblies and the light induced birefringence and dichroism. Some of the phase transitions of liquid crystalline azo polymers can be induced photochemically by the azo groups isomerization. Second order optical nonlinearity can be obtained in polymers with donor and acceptor substituted azo groups. Using the Langmuir-Blodgett technique, azo polymer monolayers can be built and used as 'command surfaces' of liquid crystal films. The light induced birefringence is a reorientation phenonmenon which is a consequence of the trans-cis-trans isomerization. Future possible applications for a variety of practical devices, such as display devices, optical modulators, optical waveguides, holography, and reversible optical storage are mentioned. Azo polymers, Review, Optoelectronic and photonic applications.

This book explores functional polymers containing aromatic azo chromophores in side-chain, main-chain and other parts of their structures, known as azo polymers and which share common photoresponsive properties. It focuses on the molecular architecture of azo polymers, the synthetic methods and their most important functions, such as photoinduced birefringence and dichroism, surface-relief-grating (SRG) formation, and light-driven deformation of liquid crystal elastomers. It combines a general survey of the subject and in-depth discussions of each topic, including numerous illustrations, figures, and photographs. Offering a balance between an introduction to the core concepts and a snapshot of hot and emerging topics, it is of interest to graduate students and researchers working in this and related fields. Xiaogong Wang is a Professor at the Department of Chemical Engineering, Tsinghua University, China.

This book is the newest research on the physical properties of optical materials used in all types of lasers and optical systems. The scope includes the most important optical materials, including crystals, glasses, polymers, metals, liquids, and gases. The properties detailed include both linear and non-linear optical properties, mechanical properties, thermal properties together with many additional special properties, such as electro-, magneto-, and elasto-optic properties.

Polymers are substances containing a large number of structural units joined by the same type of linkage. These substances often form into a chain-like structure. Starch, cellulose, and rubber all possess polymeric properties. Today, the polymer industry has grown to be larger than the aluminium, copper and steel industries combined. Polymers already have a range of applications that far exceeds that of any other class of material available to man. Current applications extend from adhesives, coatings, foams, and packaging materials to textile and industrial fibres, elastomers, and structural plastics. Polymers are also used for most composites, electronic devices, biomedical devices, optical devices, and precursors for many newly developed high-tech ceramics. This book presents leading-edge research in this rapidly-changing and evolving field.

This book offers in-depth insights into the photochemical behavior of multicomponent polymeric-based materials, with a particular emphasis on the photodegradation and photostabilization of these materials. Studying various classes of materials bases such as polysaccharides, wood, synthetic polymers, rubber blends, and nanocomposites, it offers a valuable reference source for graduate and postgraduate students, engineering students, research scholars and polymer engineers working in industry.