Processing of polymers by plasma technologies

In this paper plasma processing of polymer films and particles is examined by coating and noncoating plasmas. OTS-SAM (octadecyltrichlorosilan self-assembled monolayers) grafted to silicon wafers were used as a model to mimic the structure of PE. The authors believe that the difference by a factor of three in the etching rate between SAM and PE films in ammonia plasma is the consequence of their quasi-crystalline arrangement, compared to the amorphous PE films. For the surface treatment of polymer particles a fluidized bed low pressure plasma has been used. With the help of LDA (Laser Doppler Anemometry) measurements the real time during which the particles were exposed to the plasma was determined. A coating plasma such as allylamine was used to obtain tailored material presenting amino groups on particles. The development of the quantitative chemical derivatization assisted by UV–Visible measurements showed that it was possible to incorporate up to a maximum of 110 nmol of amino groups per gram of powders under specific conditions. Moreover, by using appropriate blocking agents, this derivatization technique allows to differentiate between primary, secondary and tertiary amino groups.