Adhesive Strength Study and Surface Analysis Using Gas-Phase Chemical Reactions of Atmospheric Pressure Plasma-treated Polypropylene

Adhesive strength of Atmospheric Pressure Glow (APG) plasma-treated polypropylene was studied for various gas mixtures by a scratching test. An explanation of the high adhesive strength obtained after He/N 2 APG plasma treatment was given. Formation of carbonyl, alcohol, carboxylic and primary amines was investigated by gas-phase chemical reaction. Their evolution during the ageing of the treated samples was followed. Most changes take place during the first few hours of contact with the atmospheric medium. Contact angle measurements on APG plasma-treated PP were done. These results were compared with PP treated by Silent Electric Discharge (SED). The ageing of the wettability properties of the surface after APG plasmas is better than after SED discharge.