Environmental Barrier

About

Technology Toxic substances pose a huge threat to human health and the environment. The approach for containing toxic substances encompasses a wide range of technologies that include personal protective equipment for workers or military personnel, geomembranes for landfill liners and caps, sealants for surfaces containing lead paint, and architectural vapor barriers to protect buildings from the intrusion of radon or volatile organic compounds. Suppressing the release of toxicants is also important in food and pharmaceutical packaging, where inks, monomers and plasticizers can leach through the polymer packaging into the product. Current containment approach typically relies on engineered barriers to prevent the transport of toxicants. However, many of those synthetic barriers are based on polymers, which are not effective barriers to small molecule permeation, especially in the vapor phase.   The invention introduces a novel way of using graphene-based layer as a barrier to permeants. This new method utilizes graphene or graphene oxide, either as a thin film or a filter, to provide an improved environmental barrier that can essentially block the transport of even small molecules, such as toxicants and vapors commonly found in landfills and other environmentally hazardous conditions. The vapor toxicants or in some cases liquid toxicants, which could permeate through the traditional polymer barrier films, can now be safely contained by this new graphene-based barrier.   This invention is widely applicable as it can be fully integrated with existing barrier materials through special surface treatment technologies. Empirical evidence has shown that it is possible to dramatically increase the barrier properties of common commodity polymer films with graphene oxide films as thin as 10 atomic layers and thus low mass loadings and low cost. Additionally the invention disclosed here is well positioned in a niche market. Although past researches have used graphene fillers to suppress the transport of oxygen and moisture, the field of using graphene-based layer as a toxicant barrier has not been explored before.