Electric properties of organic thin-layers deposited by photo-polymerization on a textile substrate

The scope of the reported experiments was to study the charging behavior of photo-polymerized poly-DAP, poly-TAE and poly-PETA thin-layers, namely the remanence or storage of artificially deposited electric charges. The thin-layers were polymerized on the fibers of a technical non-woven under variation of the main parameters of the polymerization process, namely the monomer concentration in the applied precursor and the duration of UV exposure. The charging behavior of the layers was characterized by recording the charge dissipation after defined surface charging by a corona discharge. After the artificial charging, the electric field generated by residual surface charges was measured using an electric field mill as a function of time. It was found that the poly-DAP thin-layer showed no improvement in charge decay over the untreated sample. This is attributed to water absorption due to carboxylic groups. Poly-TAE and poly-PETA showed significant increases in charge remanence with increasing polymerization. It is proposed that the observed change in the electric property is related to increased cross-linking and reduced chain mobility with increasing UV exposure. Best results were achieved with poly-TAE holding, a thin-layer holding 1/e of the initial charge after more than 10 min.