The influence of CH4 carrier gas in plasma polymerized styrene films

In this study, we prepared plasma polymerized styrene films, using the Ar and CH₄ mixture gas to investigate the potential effects of CH₄-containing reactive carrier gas on the plasma polymerized films. We investigated the variation of properties in the plasma polymerized styrene films prepared while changing the mixture ratio of CH₄ and Ar. From the results of Fourier Transform Infrared spectra (FT-IR), it was confirmed that the peak strength of products prepared under CH₄ containing carrier gas increased 1.5 ∼ 2 times than that of products only under Ar gas and the deposition rates were linearly proportional to CH₄ mixture ratio. Molecular weight distribution was studied by Pyrolysis Gas Chromatography (PyGC). In this analysis, we found out that CH₄ carrier gas resulted in the increase of deposition rates and the drop of cross-linking degrees. And these effects are considered to result from the influence of CH₄ reactive gas inflow in films. According to these results, in the case of plasma polymerization with reactive gas, it is possible to make functional thin films which have the properties of initial monomers and these films are suitable for sensors, optoelectric devices, and as resists for lithography.