sessile drop test on corona treated surface

Hello,
I study effects of corona treatment on polymer surface.
I have made a interresting test: i had treated an BCB sample whit a
afm grid (in order to have a treated and a untreated aera) and i have analysed this sample wiht AFM (view image : http://urubis.free.fr/fotos%20_seb/AFM_bcb-grid-07042004/ ) If you look to picture ( http://urubis.free.fr/fotos%20_seb/AFM_bcb-grid-07042004/Ysbs2f.tif ) you can see friction is lower where the polymer is treated than where is untreated! Normally because tip interaction it will be the opposite! I don t really know why but i think hydroxide or other oxygen or hydrogen group neutralize polarity effects .
I have read many publication about increase of ink adhesion and wettability on polymer surface .After reading I ve got the same question: This effects are they due to moleculare surface modification (incorpration of oxygen and creation of hydrogen bonding) or by the increase of the polarity?
I realize sessile drop test on polycarbonate surface whit deionize water in order to have more information. For different time (1 to 10 mim) and voltage (0 to -8kV) parameters for corona treatment I ve got the same angle (76deg)!!! I don t understant what happen:
1-there is a reaction between H2O and the oxidated surface group created during the treatment?
2-May be i have to used a other liquid, but I don t know which are usually used with polymer.
If anyone can help me it will be very nice.
And if you want to correct grammar it is ok ! no it s a joke . sorry for my english!!!
SEBASTIEN
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there are two effects: after traeatment you have eliminaten things like waxes for the process they are the reason why some prats shorws at the berinnig of work a short time higher friction than later and sometimes they are responsible for adhesive problems
the next point is you produce with Corona or Plasma a chemical bonded type of ash at the surace in German we call it "Veraschungseffekt"
but both effekts are short termed..
I am not a bug I am a undocumented feature
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