SYNTHESIS AND CHARACTERIZATION OF POLYACENE PRECURSORS

Polyacenes are one-dimensional analogs of graphite and are predicted t o have high conductivities without chemical doping. The acid-catalyzed condensation of 1,2-bis(methoxymethyl)benzene gives a network polymer with idealized structure that corresponds to a linear polyacene precu rsor, that after elimination of H-2, should yield polyacenes with exte nded pi electron systems. In contrast, the polymerization of 1,4-bis(m ethoxymethyl)benzene and 1,3-bis(methoxymethyl)benzene are expected to result in networks with a proportionately higher polybenzyl content. Based on TGA and IR studies, we propose that polyacene precursors are formed in the polymerization of the ortho substituted monomer, while t he meta and para-substituted monomers contain a higher fraction of the less stable polybenzyl structure. Samples heated in an inert atmosphe re show conversion of the acene precursors to partially graphitized pr oducts.