Quantification of Nanoparticle Release from Layer-by-layer Nanocoating on Polyurethane Foam

Y.S. Kim, R. Davis
National Institute of Standards and Technolgy, US

Keywords: nanoparticle, flame retardant, layer-by-layer, nano particle release

Summary:

There is an increasing concern about the EHS issue of conventional flame retardant (FR) materials such as halogenated FR; therefore it is necessary to develop the new generation FR, which is free from EHS issue. Previous studies have proven that nanoparticles, including montmorillonite clay, carbon nanofiber, and carbon nanotube, can significantly reduce the flammability of polyurethane foam (PUF) that are used in soft furnishings. These nanoadditives, however, may pose significant health and environmental risks if they are released from these products during routine use. These nanoparticles also change the combustion behavior of the polyurethane foam and generate large amount of fragile residue, which can be easily aerosolized after combustion. In this study, we report on our efforts to identify suitable methodologies for quantifying the release of nanoparticles from thin coatings applied to the surfaces of polyurethane foams. The nanoparticles released in simulated chewing and mechanical stressing experiments were collected in aqueous suspensions and quantified using UV-Vis and ICP-OES spectroscopy. The particle size and distribution of airborne nanoparticle due to agitation of the residue were also measured by scanning mobility particle sizer spectrometer (SMPS).