| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 692782 | Progress in Organic Coatings | 2013 | 9 Pages |
Aqueous-based inorganic–organic hybrid coating materials comprising self-assembled nanophase particles (SNAP) were investigated for their potential to confer high gas barrier performance to flexible polymeric substrates, particularly to improve suitability of the substrates as encapsulation materials for organic photovoltaic (OPV) devices. Potential benefits of this approach include versatility in barrier coating formulation to achieve specific barrier properties, and application of coatings in a reel-to-reel process under ambient conditions. The present study focused on enhancement of the oxygen barrier performance of polypropylene (PP) substrates by applying SNAP-based coatings with and without the addition of an oxygen scavenging additive. SNAP particles were characterised using 29Si NMR and dynamic light scattering, and coatings were analysed using atomic force microscopy and X-ray photoelectron spectroscopy. SNAP particle preparation and coating formulation was optimised with respect to oxygen transmission rate (OTR) of the coating on PP, and mechanical properties of the coating solution. In the absence of oxygen scavenger, the lowest OTR attained for the SNAP-based coatings was 0.87 cm3 mil m−2 day−1 atm−1. The OTR was further reduced to 0.22 cm3 mil m−2 day−1 atm−1 on addition of 9,10-anthraquinone-2,6-dissulfonic acid (AQDS) into the coating as an oxygen scavenger. These results represent a decrease in OTR by 4 orders of magnitude compared with uncoated PP, and the oxygen barrier obtained by addition of AQDS surpasses the performance of many plastic materials considered to be high oxygen barriers in the food and pharmaceutical industries.
► A barrier coating for polymer films based on nano-phase silica was developed. ► Coated films display oxygen barrier enhancement of around four orders of magnitude. ► Further enhancement was achieved by incorporating an active oxygen scavenger. ► This approach can be applied readily to a wide range of other polymer substrates. ► The technique could be used for roll-to-roll fabrication of barrier encapsulants.
