Tag Archives: intumescence

Cotton and nanotechnology at the US Dept. of Agriculture

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The April 2012 item by Jan Suszkiw of the US Dept. of Agriculture (on the Western Farm Press website) seemed strangely familiar as it focused on research into flame-retardant cotton. From the Suszkiw article,

In one ongoing project, the researchers have teamed with Texas A&M University scientists to evaluate a first-of-its-kind, environmentally friendly flame-retardant for cotton apparel and durable goods. Halogenated flame retardants have been among the most widely used chemical treatments, but there’s been a push to find alternatives that are more benign and that won’t cause treated fabric to stiffen, according to Condon [Brian Condon, Agricultural Research Service [ARS]).

I mentioned the research work in the context of a 2011 meeting of the American Chemical Society in my Sept. 6, 2011 posting (scroll down about 3/4 of the way) except the focus was on the Texas A&M University in College Station research team who had yet to collaborate with Condon’s team at the ARS,

In responding to the need for more environmentally friendly flame retardants, Grunlan’s [Jaime C. Grunlan] team turned to a technology termed “intumescence,” long used to fireproof exposed interior steel beams in buildings. At the first lick of a flame, an intumescent coating swells up and expands like beer foam, forming tiny bubbles in a protective barrier that insulates and shields the material below. The researchers are at Texas A&M University in College Station. …

Since the meeting last fall, the two teams (US ARS [Condon] and Texas A&M [Grunlan]) have collaborated to make cotton more flame retardant according to the April 2012 news article (Cotton Gets Nanotech and Biotech Treatment in New Orleans) on the US Dept. of Agriculture, Agricultural Research Service website (Note: I have removed a link),

Condon and CCUR (Cotton Chemistry and Utilization Research Unit) chemist SeChin Chang are collaborating with Texas A&M University (TAMU) scientists to evaluate a first-of-its-kind, environmentally friendly flame retardant for cotton apparel and durable goods.

Halogenated flame retardants have been among the most widely used chemical treatments for cotton. But there’s been a push to find alternatives that are not only more benign, but that also avoid imparting the same stiffness to fabric characteristic of some chemical treatments. For these and other reasons, “the textiles industry would like to move away from using halogenated flame retardants,” says Condon.

Made of water-soluble polymers, nanoscale clay particles, and other “green” ingredients, the ARS-TAMU flame retardant is applied as a nanocoating that reacts to open flame by rapidly forming a swollen, charred surface layer. This process, known as “intumescence,” stops the flame from reaching underlying or adjacent fibers.

A team led by Jaime Grunlan at TAMU’s Department of Mechanical Engineering, in College Station, Texas, originally developed the intumescent nanocoating using a layer-by-layer assembly. In this procedure, alternating layers of positively and negatively charged ingredients, including clay particles 50-100 nanometers wide, are deposited onto the surface of a desired material. The result is a striated nanocoating that, when viewed under a scanning electron or other high-powered microscope, resembles the stacked layers of a brick wall.

Condon’s interest was piqued after listening to Grunlan discuss his team’s research at a recent American Chemical Society meeting, and he approached the TAMU professor about potential benefits to cotton. That conversation, in turn, led to a cooperative research project enabling Condon and Chang to evaluate the nanocoating at CCUR.

Treating cotton for flame resistance isn’t a recent concept, adds Condon, whose lab is part of the ARS Southern Regional Research Center in New Orleans. In fact, some of the most successful early treatments were born of research conducted by Benerito [Ruth Benerito] and colleagues there several decades ago. (See “Cross-Linking Cotton,” Agricultural Research, February 2009, pp. 10-11.) Condon coauthored a 2011 ACS Nano paper on the potential of intumescent coatings together with Chang, Grunlan and his TAMU team, and Alexander Morgan of the University of Dayton Research Institute in Ohio.

Early trials of the nanocoating using standard flame-resistance tests are promising. In one case, 95 percent of treated cotton fabric remained intact after exposure to flame, whereas the untreated fabric used for comparison was completely destroyed

“What we’re investigating now is how well it will perform after repeated launderings of treated fabric,” says Condon. “After all, the coating contains clay, and that’s something detergents are made to remove.”

Even if the coating does eventually wash out and the treated fabric loses its flame resistance, the nanotech approach could still be used to protect textiles and durable goods that aren’t frequently washed, such as upholstery, mattress pads, box spring covers, automotive interiors, and firefighter coats.

This is one of the images that accompany the article,

Cross-section of a cotton fiber with clay nanoparticles attached. (from: http://www.ars.usda.gov/is/AR/archive/apr12/cotton0412.htm)

If you are interested in the work being done by the US Dept. of Agriculture’s Agricultural Research Service on cotton, there’s a lot more than I managed to excerpt.

The American Chemical Society’s 242nd national meeting, Hollywood, super heroes, and a nano intumescent flame retardant

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Apparently Hollywood came calling at the American Chemical Society’s (ACS) 242nd National Meeting (August 28 – Sept. 1, 2011). They were asking scientists to volunteer as advisors. From the August 29, 2011 news item on Science Daily,

In this International Year of Chemistry (IYC), writers and producers for the most popular crime and science-related television shows and movies are putting out an all-points bulletin for scientists to advise them on the accuracy of their plots involving lab tests, crime scenes, etc., and to even give them story ideas.

They really do want to get it right, and this is very good news for young people who absorb the information from these shows, and this helps shape their positive career decisions. That’s the message delivered in Denver by producers and writers from top television shows speaking at a special Presidential Event at the American Chemical Society’s (ACS) 242nd National Meeting & Exposition.

… They spoke at a symposium entitled “Science on the Hollywood Screen.” In addition to CSI, other shows represented were Breaking Bad, CSI New York, Buffy, Battlestar and Torchwood.

As I recall, Buffy was mainly concerned with slaying vampires. It seems a curious choice but it makes more sense when you see the presentation summaries,

Here are titles of presentations in the “Science on the Hollywood Screen” symposium, with summaries of the presentations:

  • CSI New York: Science personified. Aaron Thomas, Writer, Producer, CSI New York. For writers who do not have a science background, thorough research is essential. The producers of CSI New York go to great lengths ensuring that the stories they tell are grounded in reality. This includes the science and forensic aspects of the show. They base many of their stories on actual cases. The show has an intelligent and diligent staff of assistants who thoroughly cross-check their ideas with the latest science journals and publications to ensure that they are as accurate as possible with their research. Often, ideas that are pitched for episodes of the show begin with interesting science mysteries.
  • CSI: Entertaining science via methodology and analysis. Corrine Marrinan, Writer, Producer, CSI. Forensic chemistry and materials analysis is the cornerstone of any forensic drama, just as it is considered the strongest physical evidence to be presented in a legal case. Accurately depicting these microscopic events in entertainment is considered one of the greatest challenges in on-screen storytelling. Fortunately, advancements in forensic chemistry have developed in tandem with great advancements in the entertainment technology, special effects and computer-generated images. CSI has mastered the visual expression of forensic chemistry in order to make specialized scientific information more accessible to worldwide audiences.
  • Buffy, Battlestar, Torchwood — Chemistry vs. Magic on Sci Fi TV. Jane Espenson, writer, producer for a variety of television shows. While writers do at times attempt to include science, including chemistry, they find that magic, which serves many of the same basic functions as science, is often more adaptable. The presentation will describe a scene showing some well-researched chemistry and will include a montage of clips from various episodes that depict uses of magic, especially chemical-type potions. For chemistry to get more screen time, it would be advantageous for it to more closely resemble magic.
  • Breaking Bad: Factual and fabulous. Donna Nelson, Associate Professor of Chemistry, Massachusetts Institute of Technology (MIT) and the University of Oklahoma. The presentation will describe what it is like to be a chemist adviser for Breaking Bad and explain why more chemists should offer their talents to help producers of science-related shows and movies. Today is the perfect time for more scientists to volunteer, as show producers say they are working to create programs that are as accurate as possible.
  • Damn it, Jim (Cameron) — I’m a screenwriter not a chemist! Ann Merchant, The Science & Entertainment Exchange. The presentation will outline the mission and the history of The Science & Entertainment Exchange and examine some of the realities of the relationship between science and entertainment as a way to explore a “win-win” collaboration. It will cover the origins of The Science & Entertainment Exchange and its expertise in both the entertainment and science communities. It will also describe a “typical” consultation, highlight some of the special events The Exchange has hosted and ground the program objectives in the research on education/entertainment.

I gather the presentations were part of the ACS’s initiative celebrating the International Year of Chemistry as declared by the United Nations.

In a bid to change perceptions about scientists, a special symposium at the 242nd meeting focused on scientists as superheroes. From the August 28, 2011 news item on Nanowerk,

One of the most serious personnel shortages in the global science and engineering workforce — numbering more than 20 million in the United States alone — involves a scarcity of real-life versions of Superman, Superwoman and other superheroes and superheroines with charm, charisma, people skills and communication skills. [emphasis mine]

(Superman seems to be a theme these days. Note the recent relaunch of the Superman and other DC comic heroes in my Sept. 5, 2011 posting.)

Here’s a brief taste of what they were offering,

 

…

Infusing moving media into instruction. Janet English, Instructor, El Toro High School, Mission Viejo, Calif. The main job for movie and TV superheroes is to save the world, and this is why many consider scientists superheroes. There are numerous ways that chemists and other scientists can affect children’s learning and help promote a love of science. The media also can play a pivotal role in students’ learning, and teachers can discuss how the media is used (or not used) in a thought-provoking way in the classroom. Scientists also can contribute to improving the mass media and how they can be role models for children.

Creative engagement at science cafes. John Cohen., M.D., University of Colorado School of Medicine, Department of Immunology, Denver. A Café Scientifique brings a scientist to talk directly with the public in pleasant relaxed surroundings. PowerPoint is banned to encourage dialog, rather than a lecture. There is no moderator, so the conversation finds its correct level without imposed dumbing-down. Speakers frequently say that talking at the Café Sci was one of the best experiences of their career. So do audiences and organizers.

…

The Ig Nobel Prize: Never dull, never boring awards in chemistry. Marc Abrahams, Editor, Annals of Improbable Research. The Ig Nobel Prizes honor achievements that first make people laugh, then make them think. Every year since 1991, 10 new prizes have been awarded in chemistry, physics and other fields. The winners journey to Harvard University for the gala ceremony in which genuine Nobel laureates shake their hands and hand them their prizes. The “Igs” have spawned live shows worldwide and video features. They celebrate the unusual, honor the imaginative — and spur people’s interest in science, medicine and technology.

This next item from the meeting is the kind of presentation you’d expect at these events. An environmentally friendly and low toxicity ‘nano’ flame retardant is being developed  at Texas A&M University in College Station. From the August 31, 2011 news item on physorg.com,

 In responding to the need for more environmentally friendly flame retardants, Grunlan’s [Jaime C. Grunlan] team turned to a technology termed “intumescence,” long used to fireproof exposed interior steel beams in buildings. At the first lick of a flame, an intumescent coating swells up and expands like beer foam, forming tiny bubbles in a protective barrier that insulates and shields the material below. The researchers are at Texas A&M University in College Station.

“This work is the first demonstration of a polymer-based ‘nano intumescent’,” said Grunlan. “We believe it has great potential for use as flame retardants on clothing and other materials in order to avoid some of the disadvantages of existing products.”

Now they’ve proved that it can work, the team is now working on ways to keep the flame retardant intact through the clothes  laundering process.

Presentations in the superheroes symposium with summaries of the presentations include:

  • Science outreach: Demonstrating the value of science. Jennifer Larese, NOVA Outreach Coordinator. As individuals, people learn in slightly different manners and at different rates of speed. As informal science educators, scientists have a unique opportunity to use a variety of formats, experiences and media to engage and excite their audiences. Today there are countless new electronic media tools being created, almost daily. This presentation will briefly cover science outreach as a transmedia opportunity to connect with the public.
  • Infusing moving media into instruction. Janet English, Instructor, El Toro High School, Mission Viejo, Calif. The main job for movie and TV superheroes is to save the world, and this is why many consider scientists superheroes. There are numerous ways that chemists and other scientists can affect children’s learning and help promote a love of science. The media also can play a pivotal role in students’ learning, and teachers can discuss how the media is used (or not used) in a thought-provoking way in the classroom. Scientists also can contribute to improving the mass media and how they can be role models for children.
  • Creative engagement at science cafes. John Cohen., M.D., University of Colorado School of Medicine, Department of Immunology, Denver. A Café Scientifique brings a scientist to talk directly with the public in pleasant relaxed surroundings. PowerPoint is banned to encourage dialog, rather than a lecture. There is no moderator, so the conversation finds its correct level without imposed dumbing-down. Speakers frequently say that talking at the Café Sci was one of the best experiences of their career. So do audiences and organizers.
  • Here come the Science Festivals! Kishore Hari, Director, Bay Area Science Festival. There are many ways that science festivals are raising awareness about a tremendous grassroots movement to celebrate and elevate science. Science festivals hope to rally whole communities to celebrate science as alive and local. Festivals aim to inspire youth to consider science studies and careers, and adults to cultivate a life-long interest in science and technology.
  • The Ig Nobel Prize: Never dull, never boring awards in chemistry. Marc Abrahams, Editor, Annals of Improbable Research. The Ig Nobel Prizes honor achievements that first make people laugh, then make them think. Every year since 1991, 10 new prizes have been awarded in chemistry, physics and other fields. The winners journey to Harvard University for the gala ceremony in which genuine Nobel laureates shake their hands and hand them their prizes. The “Igs” have spawned live shows worldwide and video features. They celebrate the unusual, honor the imaginative — and spur people’s interest in science, medicine and technology.