Effect of corona pre-treatment on the performance of gas barrier layers applied by atomic layer deposition onto polymer coated paperboard

The effect of corona pre-treatment on the performance of Al2O3 and SiO2 gas barrier layers applied by atomic layer deposition onto polymer coated paperboards was studied. Both polyethylene and polylactide coated paperboards were corona treated prior to ALD. Corona treatment increased surface energies of the paperboard substrates, and this effect was still observed after several days. Al2O3 and SiO2 films were grown on top of the polymer coatings at temperature of 100 °C using the atomic layer deposition (ALD) technique. For SiO2 depositions a new precursor, bis(diethylamido) silane, was used. The positive effect of the corona pre-treatment on the barrier properties of the polymer coated paperboards with the ALD-grown layers was more significant with polyethylene coated paperboard and with thin deposited layers (shorter ALD process). SiO2 performed similarly to Al2O3 with the PE coated board when it comes to the oxygen barrier, while the performance of SiO2 with the biopolymer coated board was more moderate. The effect of corona pre-treatment was negligible or even negative with the biopolymer coated board. The ALD film growth and the effect of corona treatment on different substrates require further investigation.