Thin films, rich in primary amines (CNH2), were deposited from nitrogen (N2) or ammonia (NH3) and ethylene (C2H4) with different gas mixture ratios, R, using three different methods: atmospheric‐pressure‐ or low‐pressure plasma polymerisation (PP), and vacuum‐ultraviolet photo‐polymerisation. They are designated H‐plasma‐polymerised ethylene (PPE):N, L‐PPE:N and ultraviolet‐polyethylene (UV‐PE):N, respectively. Of interest in cell‐culture and tissue engineering, all three coating‐types were examined with regard to stability in air and solubility in water, compared with other deposits in the literature that were obtained from single precursors such as allylamine (AA) or n‐heptylamine (HA), PP‐AA and PP‐HA, respectively. The three types of deposits, prepared using comparable R values, were characterised by X‐ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, scanning electron microscopy and atomic force microscopy and found to vary significantly among themselves in regard to their [N]‐ and [NH2] concentrations, and their chemical stabilities during long‐term exposures to air or aqueous solvents. UV‐PE:N and L‐PPE:N films were found to compare very favourably with their best PP‐AA and PP‐HA counterparts; we conclude that the additional important fabrication parameter (the gas mixture ratio, R) is a major asset for preparing stable NH2‐rich organic coatings with optimal properties.

A large reactor for performing dielectric barrier discharges (DBD) experiments at atmospheric pressure (AP) has been built and tested. The area of electrodes is more than 40 times greater than that of a small DBD cell, in which we have perfected a method formeasuring E g , the energy dissipated per cycle of the applied a.c. high voltage, V a (f). This methodology has been successfully applied to plasma polymerization experiments on the larger system, using volatile organic precursors (dopants) at ‰ concentrations in 10 standard liters per minute of argon (Ar). We measured DE g , the energy difference with and without dopant, for V a (f) $ 3 kV rms (20 f 40 kHz). From DE g we then derived E tot /N, the energy per molecule, and observed surprisingly good agreement with data published in the literature relating to lowpressure (LP) plasmas.

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