Hyperbranched poly(triazene ester)s as novel globular photolabile and thermolabile polymers

Novel hyperbranched poly(triazene ester)s have been synthesized. These poly mers represent a class of polymers with photo- and thermally labile moietie s in each repeating unit. For the synthesis suitable AB(2) monomers contain ing these labile units have been designed. The polyesterification was perfo rmed at room temperature using 4-(dimethylamino)pyridinium 4-tosylate (DPTS ) as catalyst and diisopropylcarbodiimide (DiPC) as activating agent. The p olymers have been characterized by FAB-MS, SEC, DSC and H-1/C-13 NMR spectr oscopy. The degree of branching was determined by quantitative high resolut ion C-13 NMR experiments and found to be 0.5. The thermal and photochemical stability of this polytriazenes has been investigated by UV/VIS spectrosco py and thermogravimetric analysis.