Light sensitive polymers applications

A need for single-phase polymers in some applications, e.g., polytetrafluoroethylene, VHMWPE, light-sensitive polymers, etc. 

J.L.R. Williams, Fortschritte der chemischen Forschung, Springer Verlag, Berlin, Bd 13(2), pp. 227 250 (1969) G.A. Delzenne, S3mthesis and photocrosslinking of light sensitive polymers, Fur. Polym. J., Suppl., pp. 55 91 (1969) G.A. Delzenne, Photocrosslinkable polymeric systems and their technical applications, Makromol. Chem., Suppl. 2, 169 188 (1979). 

The aqua ion as a ligand is discussed in section 4.5. Silver forms a range of light-sensitive, insoluble carboxylates that find application in the synthesis of, for example, alkyl halides and esters. The benzoate, trifluoroacetate and perfluorobutyrate have dimeric structures others are polymers (Figure 4.6). 

Applications or potential applications for these molecules have been demonstrated. Molecular switches can be built using supramolecular or LC photochromic materials.1 Photochromic polymers can be used in phototropic glasses or as a basis for information recording. IR-sensitive materials have been made using biphoto-chromic molecules. Light sensitive dental materials have been developed. 

Olefin-carbon monoxide co-polymers of the type (-RCH-CH2-CO-)n, known as polyketones, have a wide variety of interesting properties, such as thermoplasticity, flexibility, durability and high impact strength. The ketone function in the polymer makes them sensitive to UV radiation and as a consequence they are photodegradable and hence environmentally acceptable plastics. However their light sensitivity has limited their applications. They can be made by the copolymerisation of an alkene with carbon monoxide (Equation 27 see also Chapter 7, Section 7.7) ... 

Other applications of sodium bromide include use in the photographic industry both to make light-sensitive silver bromide [7785-23-1] emulsions and to lower the solubility of silver bromides during the developing process use as a wood (qv) preservative in conjunction with hydrogen peroxide (14) as a cocatalyst along with cobalt acetate [917-69-1] for the partial oxidation of alkyl side chains on polystyrene polymers (15) and as a sedative, hypnotic, and anticonvulsant. The FDA has, however, indicated that sodium bromide is ineffective as an over-the-counter sleeping aid for which it has been utilized (16). 

A pH-sensitive polymer in drug delivery applications is different from other stimuli-responsive polymers that require external stimuli such as temperature and light. The pH-sensitive polymers can take advantage of variations (whether they occur naturally or under pathological conditions) of pH in the body. 

Polymers, which are used for outdoor applications are often light sensitive and must he protected from ultraviolet light in order to prevent degradation of the polymer in the final product. 

---