Sunday, June 3, 2007

24. Retardants

(asbestos, inflammable materials, deoxygenators, glass, etc.)

3 comments:

Mark said...

Inventor spurns burns with red-hot invention
By Phil Novak
BayToday.ca
Saturday, October 04, 2003

Troy Hurtubise heats a fire paste tile. Photo by Phil Novak, BayToday.ca.

Troy Hurtubise says he doesn’t feel the heat, even with a 2000° C blowtorch flame blazing at his head.

The North Bay inventor has developed a physics-defying substance called fire paste, which he claims eliminates the cross-transfer of heat and prevents anything coated in the substance from burning up.

Not only does the paste stop heat from getting through, it cools to the touch within 20 seconds of the fire source being removed.

When dry, the paste is non-toxic, four times lighter than aluminum, more heat resistant than titanium, and costs only pennies to make, Hurtubise said.

Don’t take his word for it though, because proof is available on national television.

"I should be dead by now"
Known as ‘the bear guy’ because of the Ursus bear suits he also invented, Hurtubise demonstrated the heat resistant properties of fire paste on a segment produced by and aired Sept. 2 on the Discovery Channel program Daily Planet.

In the spot, Hurtubise puts on a hockey helmet covered with a thin layer of cured fire paste and then chats casually while the live torch is held against his noggin.

“The scientists say I should be dead by now,” Hurtubise says at one point.

There’s no trickery involved, Hurtubise said, because the Discovery Channel controlled the entire sequence, even bringing the torches to North Bay in August to film the piece.

“The producer told me it was the most amazing thing he’d ever seen, that I could sit there for 10 minutes without getting my brain fried,” Hurtubise, 39, said.

Made with household ingredients
Hurtubise provided baytoday.ca with a demonstration, holding a hardened fire paste tile in his hand, while waving a blowtorch to and fro over it. He then took the tile and placed it against his face.

“Didn’t feel a thing, in fact you can touch it and see it’s cool to the touch,” Hurtubise said.

“It dissipates heat at an exponential rate, it’s beyond belief, and I have no idea why it does, all I know is that it does.”

Fire paste, Hurtubise said, is biodegradable and made with common ingredients.

“If you knew what it was made out of you’d laugh your head off for a year,” Hurtubise said during an interview in his home lab.

And the ingredients are cheap too.

Two major markets
“I can buy a 45-gallon drum of one of the main ingredients,” Hurtubise said, “for five bucks.”

Hurtubise sees two major markets for fire paste, the formula for which is locked in a safe somewhere in the United States, he said.

“I could coat the belly of the NASA space shuttle with fire paste for $25,000 (US), instead of the $60 million it costs for them to put tiles on it,” Hurtubise said.

“It can stand up to the heat of re-entry to the earth’s atmosphere, and then they can simply wash it off.”

In fact it was just three months after the space shuttle Columbia explosion that Hurtubise perfected fire paste.

Fire insurance industry interested
He said it took him 17 years of work "and 3,600 pours of the stuff," before finding the right combination.

The fire insurance industry is also interested, Hurtubise said, and has asked him to demonstrate.

He’s going to build two small-scale houses, coat one with fire paste and leave the other as is. Then they’re both going to be set on fire. When the fire paste is sprayed off, Hurtubise said, the house will be there intact.

“It will save the insurance industry billions,” Hurtubise said.

He adds that fire paste can handle such high temperatures, that had the steel skeleton holding up the World Trade Towers been sprayed with it, ...

View Photo Gallery for this Story
http://www.baytoday.ca/content/news/gallery.asp?c=63&Title=Inventor+spurns+burns+with+red%2Dhot+invention

http://www.baytoday.ca/content/news/print.asp?c=63

Mark said...

It's an insulator, retardant, purifier, catalyst, remediator, war material (perhaps to make wars impossible actually, if you think about it--indestructible things so humans applying violence to each other might be rendered useless--if equally supplied of course) and building material all rolled into one:

"Aerogel".

[Several other building materials are mentioned in this post as well, most of them not retardants though insulators instead]

from The Sunday Times
August 19, 2007
Scientists hail ‘frozen smoke’ as material that will change world

Image :3 of 3


Videos: Aerogel in the wild | 'The stuff of dreams': Aerogel in architecture | Peter Stothard on Aerogel, frozen smoke and Rupert Brooke |

A MIRACLE material for the 21st century could protect your home against bomb blasts, mop up oil spillages and even help man to fly to Mars.

Aerogel, one of the world’s lightest solids, can withstand a direct blast of 1kg of dynamite and protect against heat from a blowtorch at more than 1,300C.

Scientists are working to discover new applications for the substance, ranging from the next generation of tennis rackets to super-insulated space suits for a manned mission to Mars.

It is expected to rank alongside wonder products from previous generations such as Bakelite in the 1930s, carbon fibre in the 1980s and silicone in the 1990s.

Mercouri Kanatzidis, a chemistry professor at Northwestern University in Evanston, Illinois, said: “It is an amazing material. It has the lowest density of any product known to man, yet at the same time it can do so much. I can see aerogel being used for everything from filtering polluted water to insulating against extreme temperatures and even for jewellery.”

Aerogel is nicknamed “frozen smoke” and is made by extracting water from a silica gel, then replacing it with gas such as carbon dioxide.

The result is a substance that is capable of insulating against extreme temperatures and of absorbing pollutants such as crude oil.

It was invented by an American chemist for a bet in 1931, but early versions were so brittle and costly that it was largely consigned to laboratories.

It was not until a decade ago that Nasa started taking an interest in the substance and putting it to a more practical use.

In 1999 the space agency fitted its Stardust space probe with a mitt packed full of aerogel to catch the dust from a comet’s tail. It returned with a rich collection of samples last year.

In 2002 Aspen Aerogel, a company created by Nasa, produced a stronger and more flexible version of the gel. It is now being used to develop an insulated lining in space suits...

Mark Krajewski, a senior scientist at the company, believes that an 18mm layer of aerogel will be sufficient to protect astronauts from temperatures as low as -130C. “It is the greatest insulator we’ve ever seen,” he said.

Aerogel is also being tested for future bombproof housing and armour for military vehicles. In the laboratory, a metal plate coated in 6mm of aerogel was left almost unscathed by a direct dynamite blast.

It also has green credentials. Aerogel is described by scientists as the “ultimate sponge”, with millions of tiny pores on its surface making it ideal for absorbing pollutants in water.

Kanatzidis has created a new version of aerogel designed to mop up lead and mercury from water.

Other versions are designed to absorb oil spills.

He is optimistic that it could be used to deal with environmental catastrophes such as the Sea Empress spillage in 1996,

[the best way to 'deal with' that is to get rid of oil, period! See "Energy" category.]

when 72,000 tons of crude oil were released off the coast of Milford Haven in Pembrokeshire.

Aerogel is also being used for everyday applications. Dunlop, the sports equipment company, has developed a range of squash and tennis rackets strengthened with aerogel, which are said to deliver more power.

Earlier this year Bob Stoker, 66, from Nottingham, became the first Briton to have his property insulated with aerogel. “The heating has improved significantly. I turned the thermostat down five degrees. It’s been a remarkable transformation,” he said.

Mountain climbers are also converts. Last year Anne Parmenter, a British mountaineer, climbed Everest using boots that had aerogel insoles, as well as sleeping bags padded with the material. She said at the time: “The only problem I had was that my feet were too hot, which is a great problem to have as a mountaineer.”

However, it has failed to convince the fashion world. Hugo Boss created a line of winter jackets out of the material but had to withdraw them after complaints that they were too hot.

Although aerogel is classed as a solid, 99% of the substance is made up of gas, which gives it a cloudy appearance.

Scientists say that because it has so many millions of pores and ridges, if one cubic centimetre of aerogel were unravelled it would fill an area the size of a football field.

Its nano-sized pores can not only collect pollutants like a sponge but they also act as air pockets.

Researchers believe that some versions of aerogel which are made from platinum can be used to speed up the production of hydrogen. As a result, aerogel can be used to make hydrogen-based fuels.


* Read all 228 comments

http://www.timesonline.co.uk/tol/news/uk/science/article2284349.ece

2.

From The Times
November 16, 2005
It's the stuff of dreams
Could buildings one day be made of carbon?


Tom Dyckhoff

Mark Miodownik got a box from Nasa the other day. It contained aerogel, the lightest solid on earth. You can barely feel it, save for a slight warmth on your palm.

It’s an insulator, but was mainly used by Nasa for collecting space dust — it’s so light that even the tiniest coating is detectable.

Dr Miodownik likes it, though, for its aesthetics. It’s like bath foam, he explains, “but imagine the bubbles are a nanometre wide”, and, like bath foam, it has a blue iridescence and rainbow refraction.

“I could gaze at it all day. Imagine a building coated in it.”

Dr Miodownik, a materials scientist at King’s College London, has a vast store cupboard of these goodies — “like a giant sweet shop, and I’m in charge”.

The Engineering Art Materials Co-operative is a library not of books but of materials, both sci-fi, such as aerogel, and more commonplace, though equally amazing. Here’s tungsten, “what they make light-bulb filaments from”, only a big fist of it — “people are astonished how heavy it is”.

The point of Dr Miodownik’s sweet shop is to inspire architects, artists and designers. “These materials shouldn’t be gathering dust in science departments. They should be out there,” he says.

Engineering Art is in part a dating agency between creatives and science, through events that Dr Miodownik organises at Tate Modern to get architects, artists and designers just to feel materials, to “innovate through their fingers”, learn their properties and get them “out there” on buildings.

Their obsession with novelty means that architects are as sensitive to trends as schoolkids. Right now you can’t move for buildings made from Cor-Ten steel and ETFE, the first a metal that intentionally rusts to a rich red, the second a cladding material like bubble wrap — the Eden Project is covered in it and the world’s largest ETFE building, the national swimming centre, is being built for the Beijing Olympics.

However, “conservatism is the overriding character of the building industry,” says Graham Dodd, an associate director at Arup, the world’s most innovative engineers. “So technological innovation happens incredibly slowly.”

Dodd’s department scours the globe for new components for buildings.

“There may be technologies or materials that seem new in architecture,” he says, “but by the time they’ve reached us they’re old news.”

Architects have long fantasised about the industrial production of buildings as if they were cars or boats. Future Systems famously used boat manufacturers to construct the Media Stand at Lords because there simply wasn’t the expertise within the building industry.

Today computer-aided design means that architects can dream faster and wilder than ever. Dodd spends much of his time perfecting double curved glass panels to create seamless blobs. Engineering, the actual making of the buildings, and the things they are made from are having to catch up fast with imaginations.

In fact, says Dodd, “we are on the foothills of the most exciting period of technological change since the 1960s”.

Fugitive Materials: The Art and Science of Impermanence, with Mark Miodownik, Cornelia Parker and others, takes place at Tate Modern, SE1 (020-7887 8888), on Nov 29 at 6.30pm.

Bye, bye brick? The future of building

LiTraCon

Áron Losonczi, a Hungarian architect, laid glass fibres into structural concrete blocks before they set, rendering the light ethereal and see-through.


Nanogel

Used to insulate spaceships 30 years ago, Nanogel — sound absorbent, insulating and light transmitting — is now sandwiched within building facades.


SmartWrap

American architects have invented a new façade material made from paper-thin, polymer-based film, stuffed with air gel pockets for insulation. It can be attached with flexible solar cells and LEDs, printed with patterns and wrapped around a frame.


Electrochromic glass

We already have glass that becomes opaque by running an electric current through it. More sophisticated versions change reflectivity, glare, colour and opacity: entire glass-clad buildings might act like Reactolite sunglasses, and reducing the heat gain and loss that can make glass so energy inefficient.


Responsive environments

Spaces that communicate with their user have been one of architecture’s dreams since the Sixties. One day walls will be soft, embedded with sensors and IT, so that walls become like skin, buildings like bodies. Coating walls in nanotechnology devices is being explored too, for instance to make surfaces self-cleaning — or coating them in electronic ink so that a wall becomes one giant LCD screen. The first small SmartSlab panels will emerge in the next three years.

Carbon fibre

Imagine a skyscraper, 40 storeys high, with a helical shell entirely woven by robots from IT-embedded carbon fibre, like a cocoon. The LA architects Peter Testa and Devyn Weiser are pioneering the transfer of carbon fibre technology to architecture. Most of their projects, like the Carbon Tower, remain speculative.

http://entertainment.timesonline.co.uk/tol/arts_and_entertainment/visual_arts/architecture_and_design/article590462.ece

Mark said...

Shark-Inspired Boat Surface
Materials Engineers Turn to Ferocious Fish for Nonstick Ship Coating

May 1, 2005 — Researchers are using shark skin as a model for creating new coatings that prevent adhesion of algae and barnacles to boats.

The new coating is modeled after sharks' placoid scales, which have a rectangular base embedded in the skin with tiny spines or bristles that poke up from the surface that prevent things from attaching to the shark's skin.

GAINESVILLE, Fla.--In the boating industry, a huge problem exists that can be summed up in three words -- algae, barnacles and slime. Until now, the only way to prevent these organisms from growing was toxic paint.

But researchers are studying a more natural approach that's inspired by the ocean's fiercest predator.

In movies, they're the enemy, but in the world of science, sharks are allies.

Materials engineer Tony Brennan, of University of Florida in Gainesville, uses shark skin as a model for creating new surfaces.

"The shark scales have a roughness that approximates the roughness that we had predicted would be a good roughness to stop adhesion," he says.

Brennan designed the surfaces to prevent algae and barnacles from growing on boats. He says, "We started making surfaces that are mimicking the shark's skin."

A computer program helped researchers create the pattern and structure...

"Whatever we can draw, we can make into a surface," says UF graduate student, Jim Schumacher.

And just like shark skin, spores can't fit in the ridges and don't want to balance on top of the surface Brennan and his team designed in the lab. "That's a tremendous benefit to energy consumption, dollars and maintenance," Brennan says.

Getting rid of those barnacles and other organisms would mean less cleaning and not having to drag around the extra weight would lower fuel costs.

"If it's effective, it would tremendously affect the industry," Emerson says.

When the surface hits the market in the next year, it could impact private boaters and Navy vessels, too. Researchers are also studying the shark-coated surface for medical applications.

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http://www.sciencedaily.com/videos/2005/0505-sharkinspired_boat_surface.htm

2.

Sharks Provide Key Insight For New, Non-toxic Anti-algae Coating

ScienceDaily (Mar. 15, 2005) — GAINESVILLE, Fla. --- University of Florida engineers have developed an environmentally friendly coating for hulls of ocean-going ships based on an unlikely source of inspiration: the shark.

UF materials engineers tapped elements of sharks’ unique scales to design the new coating, which prevents the growth of a notoriously aggressive marine algae and may also impede barnacles, according to preliminary tests.

If more extensive testing and development bear out the results, the shark-inspired coating -- composed of tiny scale-like elements that can actually flex in and out to impede growth -- could replace conventional antifouling coatings. These coatings prevent marine growth but also leach poisonous copper into the ocean.

“The copper paints are wonderful in terms of keeping the ship surface clean, but they are poisonous and they accumulate at substantial rates in harbors,” threatening marine life, said Anthony Brennan, a UF professor of materials science and engineering and the lead developer of the coating. “By contrast, there are no toxins associated with our surface.”

Brennan’s project is being sponsored by the U.S. Navy, the world’s largest maritime ship owner, which has contributed at least $750,000 to the effort so far.

According to the Navy, algae and barnacles on hulls increase drag, slowing ships and reducing fuel efficiency.

Of the $550 million to $600 million the Navy spends annually on powering its ships and submarines, at least $50 million stems directly from fouling-related increased drag, said Stephen McElvany, a program officer in environmental quality in the Navy’s physical science division. The Navy hopes to find both a more effective and environmentally friendly technology than the copper-based paints.

“If achieved, this improved coating could not only be exempt from future environmental constraints and regulations, it would also provide increased fuel efficiency and velocity of Navy vessels,” McElvany said.

Brennan realized that sharks remain largely free of plants and barnacles despite spending their entire lives submerged. That contrasts, for example, some other large-bodied marine species such as whales, which attract marine growth.

Sharks have placoid scales, which consist of a rectangular base embedded in the skin with tiny spines or bristles that poke up from the surface – the reason a shark’s skin feels rough to the touch. Brennan decided [like biomimicry ideas] to try mimicking that surface with an artificial coating to see if it would also have antifouling properties.

His first product: a combination plastic/rubber coating that a microscope reveals is made of billions of tiny raised diamond-shaped patterns.

Each “sharklet” diamond measures 15 microns, or 15 thousandths of a millimeter, and contains seven raised ribs that at close examination resemble different lengths of raised horizontal bars.

Laboratory tests show that the coating prevents a very common and detrimental type of algae, called Ulva, from becoming established because the algae’s spores have great difficulty attaching to the diamond-shaped configuration.

“It normally sticks to everything, but we have reduced spore settlement by 85 percent,” Brennan said. “The only place the spores land right now is where we have a defect in the pattern.”

That’s a major advance, as the algae is a major problem for nuclear submarines, carriers and battleships because it accumulates on inlet ports used to cool nuclear reactors. “It can severely inhibit the vessel’s ability to operate,” Brennan said.

McElvany called the finding “exciting,” saying Brennan and colleagues’ research “is both unique in their approach and exciting in terms of their efficacy” in deterring the Ulva spores.

“The big hurdles that remain are to develop textures, patterns or chemistry on the surface that will also inhibit the settlement of a wide variety of the main marine foulers, such as barnacles,” he said.

The UF team, which also includes UF research scientist Ron Baney and numerous graduate students, hopes to achieve that goal with its latest version of the coating.

In research recently patented, Brennan and his colleagues have made the diamond-shaped pattern dynamic, or changeable, under the influence of a low-power electric current.

The ribs on the surfaces swell and shrink -- in effect flexing in and out from the hull surface – as the current varies.

That may be useful because the movement could prevent the accumulation of silt and other debris on the hulls, which is often a precursor to plant and barnacle growth, he said.

Both the original and newer versions of the coatings are being tested in labs in Florida, England, Hawaii, California and Australia, with full-scale ocean testing set to begin in March, Brennan said. The diversity of locations is important because each has different species of fouling plants and barnacles, he said.

The changeable version of the coating may also have an important biomedical application, Brennan said.

Tests have revealed that it can impede the attachment and growth of cells, which may make it useful on medical implants such as catheters and heart valves. Currently, cell and tissue growth on these implants often reduces or impedes their function.

“Our whole concept is a surface design that we can tailor to the application,” whether in the ocean or human body, Brennan said.

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http://www.sciencedaily.com/releases/2005/03/050310180225.htm

3.

Battling The Barnacle

ScienceDaily (Dec. 19, 2001) — For as long as we’ve been building boats and putting them in the water, we’ve been battling those pesky little ocean critters that want to attach themselves to our boats for a free ride.

The ubiquitous, determined barnacle — not to mention tubeworms, oysters, algae, and an array of other invertebrates — has long been the bane of many a fleet and flotilla.

Pitch, copper sheaths, oils and gums, pesticides, silicone, arsenic… over the centuries all have been tried, and none have completely solved the problem.

And no wonder… the barnacle, for instance, is very good at what it does. This critter secretes a rapid underwater-curing cement that is among the most powerful natural glues known — with a tensile strength of 5,000 lbs per square inch and an adhesive strength that has been measured at 22 – 60 lbs per square inch. And that’s just barnacles. Blue mussels know how to make 21 different kinds of adhesives.

Attaching themselves to ship hulls, billions of crusty foulers cost the U.S. Navy over $50 million a year just in fuel costs due to drag. It’s estimated that a newly painted destroyer would lose 2 knots of speed every six months if not scraped and cleaned — and this doubles in tropical waters.

“It’s an age-old battle,” says Dr. Steve McElvany, ONR’s Program Manager for Environmental Quality, who also studies the mechanics of adhesion. “ONR is looking hard at the development of non-toxic, foul-release polymeric marine coatings.”

The problem is the toxicity of so many of the coatings that are used worldwide. “The old copper-based coatings are now known to be lethal to some marine organisms,” says Dr. Linda Chrisey, who as manager of Environmental and Marine Biotechnology at ONR, tries to understand which organisms settle on what surfaces, and why. “An environmentally concerned U.S. Navy never implemented the widespread use of the much more toxic tin-based paints on its ships, and has been using copper-based paints since the mid-1980’s, but that’s not true throughout the world.”

Meanwhile, Dr. Paul Armistead, manager of ONR’s Polymer Chemistry program is looking for ideas to outwit the offensive critters.

One is a flexible coating — organisms might try to settle on a ship but wouldn’t be able to grip tightly, allowing the organisms to adhere when the ship is in port, but sloughing them off once the ship reached cruising speed.

Yet another idea might be found in textured hull coatings, where the very nature of the shape of the coating (i.e., pattern dimensions and surface energies), might be repugnant to the fouling organisms.

“Nothing is quite as easy as it sounds,” says Armistead. “The silicone based paints are fragile and scrape easily, although we are seeking to improve this with research on [even more toxic!] nano-composite additives. The textured coatings look promising for repelling barnacles, but not other types of foulers.

And some of the other coatings we’re looking at seem to repel the fouling invertebrates, but confound us by attracting seaweed.”

Nevertheless, the Navy knows how to stick to things, too. In a recent Broad Agency Announcement (BAA), ONR solicited proposals in basic and applied research in the age-old battle of the barnacle, and is evaluating those proposals now.

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http://www.sciencedaily.com/releases/2001/12/011219062137.htm