Chemical modification of polymers via phase transfer catalysis

Functional polymers such as polymeric supports, polymeric reagents, poly­meric catalysts, polymeric drugs, photoresists, polymeric photosensitizers and other photoresponsive polymers have long been of interest [1] in the field of polymer chemistry because they have great promise for advancing the science of chemistry and developing new industrial applications. Although these polymers have been synthesized by various methods, these synthetic processes can be divided roughly into two different types: synthesis of func­tional polymers by the direct polymerization of the corresponding monomers having functional groups, and the chemical modification of polymers using appropriate reagents. Each method has advantages and disadvantages. The former is the preferred method for introducing functional groups efficiently into the polymer chain; however, the polymerization of monomers is occa­sionally hindered by the functional groups in the molecules. The isolation and purification of functional monomers are also not easy. Accordingly, there are some limitations and technical problems in the synthesis of func­tional polymers by the direct polymerization of functional monomers.