DETERMINATION OF THE AVERAGE MOLECULAR-WEIGHT OF POLY(P-PHENYLENEVINYLENE)

For any polymer the determination of the average molecular weight and its distribution is an important part of characterising its physical p roperties. We report values for the MnBAR, MwBAR and dispersity, deter mined using gel permeation chromatography, of a neutral precursor poly mer to poly(p-phenylenevinylene) in relation to polymerisation conditi ons. We have observed a maximum MnBAR value of approximately 100,000 w ith a dispersity of 5.7 and compare this value to that calculated for the ''effective conjugation length'', that is the number of repeat uni ts over which uninterrupted pi-electron delocalisation actually takes place, in fully converted poly(p-phenylenevinylene).