Nanotechnology Now

Our NanoNews Digest Sponsors





Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > Novel Clay-based Coating May Point the Way to New Generation of Green Flame Retardants

Using a testing device called a cone calorimeter, NIST researchers measure the heat-release rate and other flammability properties of materials. Above, untreated polyurethane foam 'catches fire' from a nearby heat source. Below, foam treated with a novel clay-filled coating did not ignite when exposed to the same heat source. Instead, a fast-growing protective layer called char forms on the surface.
Credit: NIST
Using a testing device called a cone calorimeter, NIST researchers measure the heat-release rate and other flammability properties of materials. Above, untreated polyurethane foam 'catches fire' from a nearby heat source. Below, foam treated with a novel clay-filled coating did not ignite when exposed to the same heat source. Instead, a fast-growing protective layer called char forms on the surface.

Credit: NIST

Abstract:
In searching for better flame retardants for home furnishings—a large source of fuel in house fires—National Institute of Standards and Technology (NIST) researchers defied the conventional wisdom and literally hit a wall, one made of clay.

Novel Clay-based Coating May Point the Way to New Generation of Green Flame Retardants

Gaithersburg, MD | Posted on June 28th, 2012

It wasn't a dead end, but rather a surprising result that may lead to a new generation of nonhalogenated, sustainable flame retardant technology for polyurethane foam. The thick, fast-forming coating that the NIST team created has a uniformly high concentration of flame-inhibiting clay particles, and it adheres strongly to the Swiss cheese-like surface of polyurethane foam, which is used in furniture cushions, carpet padding, children's car seats, and other items.

"In effect, we can build the equivalent of a flame-retarding clay wall on the foam in a way that has no adverse impact on the foam manufacturing process," explains NIST fire researcher Rick Davis. "Our clay-based coatings perform at least as well as commercial retardant approaches, and we think there's room for improvement. We hope this new approach provides industry with practical alternative flame retardants."

Davis and his NIST colleagues describe the new coating and the process they used to make it in the journal ACS Macro Letters.*

To date, researchers have built up coatings by stacking thin layers in pairs that are held together by basic electrical attraction. With no clay present, just a pure polymer, a thick coating is formed rapidly, but it isn't a fire retardant. With clay in every other layer, either the coating is too thin or the clay content is too low to be an effective fire retardant.

The NIST team tried something you would expect not to work: trilayers consisting of a positively charged bottom topped by two negatively charged layers. Under most circumstances, the two negative layers would repulse each other, but it turns out that hydrogen bonds formed between the two negative layers and overcame this repulsive force.

The resulting trilayer yields a unique result: a thick, fast-forming, and high concentration clay coating on polyurethane foam. This nanocomposite coating is 10 times thicker, contains 6 times more clay, and achieves this using at least 5 times fewer total layers than the traditional bilayer coatings.

"The eight trilayer system thoroughly coated all internal and external surfaces of the porous polyurethane foam, creating a clay brick wall barrier that reduced foam flammability by as much as 17 percent of the peak heat release rate," the team reported. Only a few hundred nanometers thick, the final coating is transparent and the foam still has the same softness, support and feel.

Compared with amounts of current flame retardant applied to polyurethane foam, only half as much of the new clay-based coating was required to achieve comparable levels of performance.

* Y.S. Kim, R. Harris and R. Davis. Innovative approach to rapid growth of highly clay-filled coatings on porous polyurethane foam. ACS Macro Letters, 2012, 1, 820−824. .dx.doi.org/10.1021/mz300102h

####

About National Institute of Standards and Technology (NIST)
The National Institute of Standards and Technology (NIST) is an agency of the U.S. Department of Commerce.

For more information, please click here

Contacts:
Mark Bello
301-975-3776

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 News Press

News and information

Multi-million pound project to use nanotechnology to improve safety September 4th, 2015

Magnetic wormhole connecting 2 regions of space created for the first time: The device could have applications in medicine, opening up ways to make MRIs more comfortable for patients September 4th, 2015

Tongfang Global and QD Vision Partner to Bring Wide Color Gamut to Global Television Lines: Color IQTM quantum dots help boost company’s focus on superior color reproduction September 3rd, 2015

QEOS and GLOBALFOUNDRIES to Offer Industry’s First CMOS Platform for MillimeterWave Markets: GLOBALSOLUTIONSSM Partnership will enable next-generation wireless technologies for applications in IoT, 5G and automotive September 3rd, 2015

Laboratories

An engineered surface unsticks sticky water droplets August 31st, 2015

New material science research may advance tech tools August 31st, 2015

Major innovation in molecular imaging delivers spatial and spectral info simultaneously: Berkeley Lab scientist invents technique to combine spectroscopy with super-resolution microscopy, enabling new ways to examine cell structures and study diseases August 17th, 2015

Drexel engineers 'sandwich' atomic layers to make new materials for energy storage August 15th, 2015

Govt.-Legislation/Regulation/Funding/Policy

Magnetic wormhole connecting 2 regions of space created for the first time: The device could have applications in medicine, opening up ways to make MRIs more comfortable for patients September 4th, 2015

Making nanowires from protein and DNA September 3rd, 2015

Making fuel from light: Argonne research sheds light on photosynthesis and creation of solar fuel September 3rd, 2015

Reversible Writing with Light: Self-assembling nanoparticles take their cues from their surroundings September 3rd, 2015

Discoveries

Magnetic wormhole connecting 2 regions of space created for the first time: The device could have applications in medicine, opening up ways to make MRIs more comfortable for patients September 4th, 2015

QEOS and GLOBALFOUNDRIES to Offer Industry’s First CMOS Platform for MillimeterWave Markets: GLOBALSOLUTIONSSM Partnership will enable next-generation wireless technologies for applications in IoT, 5G and automotive September 3rd, 2015

Making nanowires from protein and DNA September 3rd, 2015

Making fuel from light: Argonne research sheds light on photosynthesis and creation of solar fuel September 3rd, 2015

Announcements

Multi-million pound project to use nanotechnology to improve safety September 4th, 2015

Magnetic wormhole connecting 2 regions of space created for the first time: The device could have applications in medicine, opening up ways to make MRIs more comfortable for patients September 4th, 2015

Making nanowires from protein and DNA September 3rd, 2015

Making fuel from light: Argonne research sheds light on photosynthesis and creation of solar fuel September 3rd, 2015

Home

Industrial Nanotech, Inc. Provides Update on PCAOB Audited Financials July 27th, 2015

Solar cells in the roof and nanotechnology in the walls June 16th, 2015

Industrial Nanotech, Inc. Continues Global Development Focus on Original Equipment Manufacturer (OEM) Applications: Industrial Nanotech Continues Connecting With Manufacturers Who Seek Out Their Patented Thermal Insulation and Protective Coatings June 11th, 2015

Industrial Nanotech, Inc. Article About the Evolution of Roof Coatings in Durability + Design Magazine June 9th, 2015

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



  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project







Car Brands
Buy website traffic