Effect of corona discharge on the selected properties of polylactide surface layer intended for autocatalytic metallization

The effect of the modification of poly(lactic acid) (PLA) surface layer using corona treatment in air or nitrogen was evaluated by determination of oxidation degree, contact angle measurements and surface free energy calculations. It was found that as a result of corona discharge the degree of PLA sur- face layer oxidation increases independently of the applied unit activation energy E j as well as the type of atmosphere used. However, the degree of nitriding of the samples modified under nitrogen increases with an increase of E j value and is higher than for the samples modified in air. It was also found that coro- na discharges in both air and nitrogen atmospheres result in the changes in contact angle values of water and diiodomethane on PLA surface layer as well as an increase of surface free energy.