Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button

Home > Press > NIST-made 'sun and rain' used to study nanoparticle release from polymers

NIST researchers simulate "sun and rain" to determine if weathering causes polymer coatings to release the nanoparticles they contain into the environment. On the left, Li-Piin Sung places a commercially available polymer with silicon dioxide nanoparticles into a chamber of the NIST SPHERE, a device for accelerated weathering that in one day subjects samples to the equivalent of 10-15 days of outdoor exposure. On the right, Deborah Jacobs applies "NIST simulated rain" to the weathered sample to collect any shed nanoparticles in the runoff.
CREDIT: Fran Webber/NIST
NIST researchers simulate "sun and rain" to determine if weathering causes polymer coatings to release the nanoparticles they contain into the environment. On the left, Li-Piin Sung places a commercially available polymer with silicon dioxide nanoparticles into a chamber of the NIST SPHERE, a device for accelerated weathering that in one day subjects samples to the equivalent of 10-15 days of outdoor exposure. On the right, Deborah Jacobs applies "NIST simulated rain" to the weathered sample to collect any shed nanoparticles in the runoff.

CREDIT: Fran Webber/NIST

Abstract:
If the 1967 film "The Graduate" were remade today, Mr. McGuire's famous advice to young Benjamin Braddock would probably be updated to "Plastics ... with nanoparticles." These days, the mechanical, electrical and durability properties of polymers--the class of materials that includes plastics--are often enhanced by adding miniature particles (smaller than 100 nanometers or billionths of a meter) made of elements such as silicon or silver. But could those nanoparticles be released into the environment after the polymers are exposed to years of sun and water--and if so, what might be the health and ecological consequences?

NIST-made 'sun and rain' used to study nanoparticle release from polymers

Gaithersburg, MD | Posted on October 5th, 2016

In a recently published paper, researchers from the National Institute of Standards and Technology (NIST) describe how they subjected a commercial nanoparticle-infused coating to NIST-developed methods for accelerating the effects of weathering from ultraviolet (UV) radiation and simulated washings of rainwater. Their results indicate that humidity and exposure time are contributing factors for nanoparticle release, findings that may be useful in designing future studies to determine potential impacts.

In their recent experiment, the researchers exposed multiple samples of a commercially available polyurethane coating containing silicon dioxide nanoparticles to intense UV radiation for 100 days inside the NIST SPHERE (Simulated Photodegradation via High-Energy Radiant Exposure), a hollow, 2-meter (7-foot) diameter black aluminum chamber lined with highly UV reflective material that bears a casual resemblance to the Death Star in the film "Star Wars." For this study, one day in the SPHERE was equivalent to 10 to 15 days outdoors. All samples were weathered at a constant temperature of 50 degrees Celsius (122 degrees Fahrenheit) with one group done in extremely dry conditions (approximately 0 percent humidity) and the other in humid conditions (75 percent humidity).

To determine if any nanoparticles were released from the polymer coating during UV exposure, the researchers used a technique they created and dubbed "NIST simulated rain." Filtered water was converted into tiny droplets, sprayed under pressure onto the individual samples, and then the runoff--with any loose nanoparticles--was collected in a bottle. This procedure was conducted at the beginning of the UV exposure, at every two weeks during the weathering run and at the end. All of the runoff fluids were then analyzed by NIST chemists for the presence of silicon and in what amounts. Additionally, the weathered coatings were examined with atomic force microscopy (AFM) and scanning electron microscopy (SEM) to reveal surface changes resulting from UV exposure.

Both sets of coating samples--those weathered in very low humidity and the others in very humid conditions--degraded but released only small amounts of nanoparticles. The researchers found that more silicon was recovered from the samples weathered in humid conditions and that nanoparticle release increased as the UV exposure time increased. Microscopic examination showed that deformations in the coating surface became more numerous with longer exposure time, and that nanoparticles left behind after the coating degraded often bound together in clusters.

"These data, and the data from future experiments of this type, are valuable for developing computer models to predict the long-term release of nanoparticles from commercial coatings used outdoors, and in turn, help manufacturers, regulatory officials and others assess any health and environmental impacts from them," said NIST research chemist Deborah Jacobs, lead author on the study published in the Journal of Coatings Technology and Research.

This project resulted from a collaboration between NIST's Engineering Laboratory and Material Measurement Laboratory. It is part of NIST's work to help characterize the potential environmental, health and safety (EHS) risks of nanomaterials, and develop methods for identifying and measuring them.

####

For more information, please click here

Contacts:
Michael E. Newman

301-975-3025

Copyright © National Institute of Standards and Technology (NIST)

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related Links

D.S. Jacobs, S-R Huang, Y-L Cheng, S.A. Rabb, J.M. Gorham, P.J. Krommenhoek, L.L. Yu, T. Nguyen and L. Sung. Surface degradation and nanoparticle release of a commercial nanosilica/polyurethane coating under UV exposure. September 2016. Journal of Coatings Technology and Research.

Related News Press

News and information

Big award enables study of small surfaces: Rice U.'s Matt Jones wins Packard Fellowship to view nanoscale chemical reactions October 15th, 2018

Arrowhead Pharmaceuticals Files for Regulatory Clearance to Begin Phase 1 Study of ARO-ANG3 October 15th, 2018

Graphene shows unique potential to exceed bandwidth demands of future telecommunications October 12th, 2018

High-performance self-assembled catalyst for SOFC October 12th, 2018

Laboratories

Cannibalistic materials feed on themselves to grow new nanostructures September 1st, 2018

A Novel Graphene Quantum Dot Structure Takes the Cake August 24th, 2018

Virginia Tech researchers develop novel process to 3D print one of the strongest materials on Earth August 23rd, 2018

Connecting the (Nano) Dots: NIST Says Big-Picture Thinking Can Advance Nanoparticle Manufacturing August 22nd, 2018

Marine/Watercraft

Relax, just break it July 20th, 2018

Nanowrinkles could save billions in shipping and aquaculture Surfaces inspired by carnivorous plants delay degradation by marine fouling January 17th, 2018

'Quantum material' has shark-like ability to detect small electrical signals December 20th, 2017

Promising sensors for submarines, mines and spacecraft: MSU scientists are developing nanostructured gas sensors that would work at room temperature November 10th, 2017

Govt.-Legislation/Regulation/Funding/Policy

Arrowhead Pharmaceuticals Files for Regulatory Clearance to Begin Phase 1 Study of ARO-ANG3 October 15th, 2018

Graphene shows unique potential to exceed bandwidth demands of future telecommunications October 12th, 2018

High-performance self-assembled catalyst for SOFC October 12th, 2018

Tracking a Killer: UCSB, UCSD and SBP researchers trace the complex and variable pathways to the deadly condition known as sepsis October 12th, 2018

Possible Futures

Researchers quickly harvest 2-D materials, bringing them closer to commercialization: Efficient method for making single-atom-thick, wafer-scale materials opens up opportunities in flexible electronics October 12th, 2018

Graphene shows unique potential to exceed bandwidth demands of future telecommunications October 12th, 2018

High-performance self-assembled catalyst for SOFC October 12th, 2018

180 Degree Capital Corp. Announces New Portfolio Holdings Airgain, Inc., EMCORE Corporation, Lantronix, Inc. and PDL BioPharma, Inc. October 12th, 2018

Discoveries

Researchers quickly harvest 2-D materials, bringing them closer to commercialization: Efficient method for making single-atom-thick, wafer-scale materials opens up opportunities in flexible electronics October 12th, 2018

Graphene shows unique potential to exceed bandwidth demands of future telecommunications October 12th, 2018

High-performance self-assembled catalyst for SOFC October 12th, 2018

Tracking a Killer: UCSB, UCSD and SBP researchers trace the complex and variable pathways to the deadly condition known as sepsis October 12th, 2018

Announcements

Big award enables study of small surfaces: Rice U.'s Matt Jones wins Packard Fellowship to view nanoscale chemical reactions October 15th, 2018

Arrowhead Pharmaceuticals Files for Regulatory Clearance to Begin Phase 1 Study of ARO-ANG3 October 15th, 2018

180 Degree Capital Corp. Announces New Portfolio Holdings Airgain, Inc., EMCORE Corporation, Lantronix, Inc. and PDL BioPharma, Inc. October 12th, 2018

TUBALL single wall carbon nanotubes: No ecotoxicity found, unlike other carbon nanotubes October 12th, 2018

Interviews/Book Reviews/Essays/Reports/Podcasts/Journals/White papers

Big award enables study of small surfaces: Rice U.'s Matt Jones wins Packard Fellowship to view nanoscale chemical reactions October 15th, 2018

Graphene shows unique potential to exceed bandwidth demands of future telecommunications October 12th, 2018

High-performance self-assembled catalyst for SOFC October 12th, 2018

Tracking a Killer: UCSB, UCSD and SBP researchers trace the complex and variable pathways to the deadly condition known as sepsis October 12th, 2018

Safety-Nanoparticles/Risk management

TUBALL single wall carbon nanotubes: No ecotoxicity found, unlike other carbon nanotubes October 12th, 2018

Silver nanoparticles are toxic for aquatic organisms: A research team at the UPV/EHU-University of the Basque Country has analysed how zebrafish are affected in the long term by exposure to silver particles September 19th, 2018

Carbon nanodots do an ultrafine job with in vitro lung tissue: New experiments highlight the role of charge and size when it comes to carbon nanodots that mimic the effect of nanoscale pollution particles on the human lung. September 12th, 2018

A human enzyme can biodegrade graphene August 28th, 2018

NanoNews-Digest
The latest news from around the world, FREE



  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project