March 8, 2005 > Spray-on Defense
by Venkat Raman
Line-X, recognized as a top spray-on truck bed liner product designed to prevent dents and scratches, has been commissioned by the federal government to protect key buildings with its blast-proof paint.
As part of the Homeland Security initiative, the patented Line-X PAXCON has been applied to the walls of the U.S. Pentagon, the Washington D.C. Naval Base and a federal courthouse in New York City. Other structures like state, county and city buildings, bridges, dams and nuclear power plants will likely become logical candidates for anti-terrorism protection. Besides blast mitigation, other military applications include lining submarines, ships, Humvees, and helicopter pads.
"We have got a solution that can protect lives in the war on terrorism. It is interesting that it came from our solution to protect the beds of pick up trucks. This is a really good technology transfer," said Scott Jewett, blast mitigation and ballistics expert at Line-X Corporation.
The suitability of Line-X for blast mitigation suggests that it is ideal for peacetime projects such as earthquake protection, where the damage arises from accidents and natural causes. The abrasion resistance and the weather seal properties lend themselves to innumerable applications in day-to-day life.
Claudio Burtin, a principal in Burtin Chemical Corporation and sometime racecar driver, originally developed Line-X more than two decades ago for commercial use in the polyurethane foam industry. After 10 years of research Line-X was born. When he coated the floor of a racecar trailer, it gained instant popularity.
The basic principle behind Line-X is to mix two chemical agents (a hardener and resin) creating a polymer that cures in a short amount of time - within five seconds - and exhibits strong bonding with any surface that it touches during the curing process. The result is similar to the bottom of heavy duty work boots. The polymer is extremely resistant to weathering and rough use. Line-X is also a flexible material and bonds to a irregular surfaces quickly.
The Khobar Towers bombing in Dhahran, Saudi Arabia in June 1996 prompted the U.S. government to evaluate the use of elastomeric polymers to protect occupants in structures susceptible to bombing. It was observed that most bomb damage was the result of fragmentation - broken pieces of the concrete masonry unit (CMU) structure injuring occupants as shrapnel.
In a test conducted by the Air Force Research Laboratory, Line-X, and 26 other such products were evaluated in various bomb blast scenarios. Line-X was the only product that passed all tests. Vivid photographs taken during test blasts show dummies decapitated by fragmented cement blocks. The Air Force Research Lab found that it took 1,000 pounds equivalent of TNT to make Line-X fail - the material tore at that point but it was still able to prevent fragmentation. In other words, the bombed walls flexed but held together.
"An unreinforced CMU wall normally fails at about five or six PSI. The test results where Line-X held up well was at 90 PSI - about 18 times the pressure. And this was just with a quarter inch thickness of our product," said Jewett.
The Energetic Materials Research and Testing Center (EMRTC), a division of New Mexico Institute of Mining and Technology, conducted a study of Line-X and published a report in August 2004 on retrofit of unreinforced concrete walls for blast protection. The recommendation was to line both the interior and the exterior walls with quarter-inch thick Line-X for maximum protection.
It is worthwhile noting that Line-X is an environmentally friendly material; it does not generate any known hazards to the environment. It is, in fact, approved for use in food preparation systems as well as drinking water systems. It does not flake or peel with age.
Over the years, Line-X has become a nationwide franchise. Headquartered in Santa Ana, California, Line-X has over 400 dealer/franchises around the world, extending as far as Europe, Asia and South America.
To learn more about Line-X, visit www.line-x.com or contact Brian King at (510) 770-8881. To read more about military applications of Line-X, visit www.paxcon.com.