Controlling the molecular weight of poly(2,5‐bis[N‐methyl‐N‐hexylamino]phenylene vinylene) using nitrobenzene as an inhibitor

Abstract

Poly(2, phenylene vinylene) (BAM-PPV) has been studied for several decades as an anti-corrosion coating. Although the polymer is readily synthesized via base-promoted radical chain polymerization, BAM-PPV exhibits poor solubility at high-molecular weights (M w > 100 kDa), which limits its applications. In this work, the molecular weight of BAM-PPV was modulated with nitrobenzene. At nitrobenzene loading as low as 0.9 mol %, the polymerization reaction produced low-molecular weight BAM-PPV (M w = 5-46 kDa). The polymerization of BAM-PPV was systematically studied via size-exclusion chromatography (SEC), liquid chromatography-mass spectrometry (LC-MS), and 1 H NMR spectroscopy, which revealed suppression of the dimer intermediate before chain polymerization. Collectively, this work could expand the practical applications of BAM-PPV for use in optoelectronic devices or corrosion inhibition coatings.