Nanoparticles are increasingly incorporated in flooring coatings and interior paints to improve their abrasion and microbial resistance. One particular concern of this application is the release of nanoparticles from these surfaces due to repeated mechanical forces acted upon them, such as walking, mopping, cleaning, scratching, and furniture moving. Such release of the nanosize material is potentially harmful to the occupants particularly children. Because of this serious concern, CPSC and NIST has an agreement to develop testing and measurement protocols for determining the quantities and properties of nanoparticles released from flooring coatings and interior paints. The first year of this research was to develop instrumentation, protocols, and analytical methods to measure released particles resulting abrasion in air from coatings and paint containing a known amount of nanoparticles. The 2nd year of the research has investigated the development of methods and protocols for abrasion of flooring coatings and interior in liquid and to measure and identify the particles remained on the surface and in liquid. This report summarizes Year 2 research, which used commercial flooring nanocoating and interior nanopaint. It includes 1) Characterizations of inorganic materials in the commercial nanoproducts and initial properties before and after immersion in water, 2) development of methods and protocols for abrasion in liquid of flooring nanocoating and interior nanopaint, 3) measurement and identification of released particles remained on the abraded surfaces and suspended in liquid, and 4) investigation to develop an appropriate wheel that can reproducibly abrade nanocoating and nanopaint surfaces in air and in liquid. The Year 2 research also investigated the fabrication of a chamber and methods to quantify the number and size of nanoparticles aerosolized during abrasion in air.
Technical Note (NIST TN) - 1835
abrasion, EDS, coatings, confocal miscroscopy, ICP, mass loss, nanoparticle release, SEM, TGA