Nucleation and growth of gas barrier aluminium oxide on surfaces of poly(ethylene terephthalate) and polypropylene: effects of the polymer surface properties
SiOx barrier films were deposited on poly (ethylene terephthalate) (PET) by radio frequency (RF) magnetron co-sputtering with double targets. The films deposited by co-sputtering were denser and smoother because different energy particles sputtering from double targets grew small islands to weaken shadowing effect which greatly reduce the interval gaps. The water vapor and oxygen transmission of SiOx films deposited by co-sputtering decreased to 0.31 cc/m2/day, 0.27 g/m2/24h respectively.
In an attempt to enhance the gas barrier enhancement of plastic containers such as poly(ethylene terephthalate) bottles, a novel method was found using a hot wire CVD technique, where tantalum wire is heated and exposed to a gas flow of vinyl silane. The resultant SiOC thin film was confirmed to characteristically contain Si-Si bonds in its surface and demonstrate a remarkably and highly practical decrease of the permeation of various gas through poly(ethylene terephthalate) bottles.
Red phosphorus/aluminium oxide compositions as flame retardants in recycled poly(ethylene terephthalate)