Photopolymerization of pyrrole/methacrylate mixtures using alpha-cleavage type photoinitiators in combination with iodonium salt

SILVANA ASMUSSEN; GUSTAVO ARENAS; CLAUDIA VALLO

SYNTHETIC METALS

ELSEVIER SCIENCE SA

Lugar: Amsterdam; Año: 2015 vol. 209 p. 304 - 312

0379-6779

Hybrid systems formulated with pyrrole and methacrylate monomers were photopolymerized with bothUV (l = 365 nm) and visible (l = 470 nm) light. It is known that conducting polymers produced byelectrochemical or chemical synthesis are intractable solids or powders which display poor mechanicalproperties and low processability. An advantage of the photopolymerization process is that it allowsprocessability and mechanical properties offinal polymers to be optimized by incorporatingflexibilizersand different additives into photopolymerizable formulations. Mixtures pyrrole/methacrylate werephotoactivated with the iodonium salt p-(octyloxyphenyl)phenyliodonium hexafluoroantimonate(Ph2ISbF6), in combination with 2,2-dimethoxy-2-phenylacetophenone (DMPA), 2-methoxy-2-phenyl-acetophenone (BZME) or the pair camphorquinone (CQ)/ethyl-4-dimethylamino benzoate (EDMAB). ThePh2ISbF6 in combination with DMPA or BZME was an efficient photoinitiator system under irradiation at365 nm. Conversely, in mixtures photoactivated with Ph2ISbF6/CQ/EDMAB the polymerization of bothpyrrole and methacrylate was comparatively slow. Microscopy studies revealed the absence of phaseseparation indicating that the mixtures pyrrole/methacrylate resulted in the formation of aninterpenetrating polymer network. The electrical conductivity of the hybrid polymers increasedmarkedly with the amount of polypyrrole as a result of the formation of a conducting polymer network inthe insulating BisEMA matrix.