Polymer chemistry, singlet oxygen

Polymer Rose Bengal was synthesized using Merrifield chemistry [296] from chloromethylated polystyrene beads [297] and has quantum yields of singlet oxygen formation about the same as does Rose Bengal in similar solvents. It does not bleach, does not undergo self-quenching, and therefore seems not susceptible to electron transfer between dye molecules, a phenomenon induced by dye site isolation on the backbone of the polymer. 

This paper is an interpretation of the primary photo-oxidation process due to singlet oxygen and some problems in photostablll-zatlon of polymers and plastics. Electronic structure, generation, properties and role of singlet oxygen in polymer chemistry are discussed. The reader is also referred to a number of review articles on the subject (1-11). 

Recently it has been reported,that singlet oxygen oeui be produced by the dismutation reaction of superoxide cmionie radicals (see chemical generation of singlet oxygen,page of this paper)(31 33) Superoxide anionic radicals take part in several polymer reactions,and are also important species in biopolymer chemistry. 

The importance of singlet oxygen in polymer chemistry should ha considered from three aspectst... 

Dye and pigment fading and sensitization continue to be highly active areas of interest especially with regard to photocatalytic chemistry. The sensitized production of singlet oxygen is known to play an important role in polymer oxidation reactions with dyes. Zinc phthalocyanine sulfonate is widely used to... 

This paper reviews polymeric photosensitizers from the first case indicating that the concept was possible to polymer-rose bengal. The review focuses on the chemistry of the appended small molecule, and the role of the polymer. The most important polymeric photosensitizer to date is polymer rose bengal - a heterogeneous source of singlet oxygen and the most extensive review is of this system. 

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