Surface and adhesion changes of atmospheric barrier discharge-treated polypropylene in air and nitrogen

摘要

Oriented polypropylene treated by atmospheric barrier discharges in air and nitrogen was investigated using several techniques:contact angle measurements,ATR-FT-IR spectroscopy and two adhesion tests based on the stripping of an applied ink layer.The activation in an air dischange was found to be much weaker compared to the activation in industrial grade nitrogen,particularly with respect to adhesion.The adhesion was found to be much better in nitrogen in spite of the common use of air in industrial 'corona discharges'.A new 'abrasive shear-stripping' (AS) test for ink coating adhesion was designed and performed.It was shown that the AS test was much more sensitive than the classical adhesive tape test and was senstive enough to monitor ageing and overtreatment.The contact angle measurements did not correlate completely with the adhesio properties and could not monitor teh overtreatment,while the ATR-FT-IR technique indicated changes just for overtreated foils.