Remote nitrogen plasma treatment of a polyethylene powder Optimisation of the process by composite experimental designs

A coupling between fluidised bed and far cold remote nitrogen plasma technologies is used to treat a polyethylene powder in order to increase its wettability evaluated from capillarity rising measurements. An optimisation of the process is performed thanks to face-centred central composite experimental designs. It is shown that treatment duration and oxygen rate added to nitrogen are the more influent parameters. Electron spin resonance analyses revealed the presence of a mixture of alkyl and allyl radicals on the treated powder. Reactions leading to the incorporations of new chemical functions on the polyethylene surface are proposed.