Synthesis and characterization of photoactive poly(arylene ether sulfone)s containing azobenzene moieties in their main chains

A series of azobenzene functionalized poly(arylene ether sulfone)s (azo-PAESs) has been synthesized via nucleophilic aromatic substitution polycondensation, and azobenzene chromophores could be introduced into the polymer main chains by copolymerization from azo-monomers. These main chain type azo-PAESs have high glass transition temperatures and good thermal stability. Exposed to an interference pattern laser beam, spin-coated films of the azo-PAESs can form clear and stable surface relief gratings (SRGs). These SRGs show increased thermal stabilities with the content of azo moieties and cannot be fully removed until the temperature increases to 300 °C for azo-PAESs with a content of azo segments above 50%.