Line-X: The Spray That Can Make Anything Indestructible

A unique spray coating developed by Line-X has the incredible capacity to enable almost anything to become seemingly indestructible!

Line-X is an industry leader in tough materials and has been for the last 20 years. Their line of virtually indestructible spray on coatings is no exception. The spray is an amazing chemical concoction that binds onto almost any material, adding another layer of protection and toughness. The coating is rated as safe for use in potable water containers, use around animals, and many, many other applications.

The coating is thin, yet provides an impeccable, virtually impenetrable shield. Below you can see the effectiveness of the coating in action and the difference it makes.

Implementing a thin coating of a variant of LineX is enough to allow some flexion of a wall while retaining its strength. The experiment was set up with two identical concrete structures built side by side. One was coated with Paxon, the other was left untreated. The setting was completed with an office type setup with a desk and a dummy- and 200lb equivalent of TNT. The blast was set off 30-feet away from the structures. The results are incredible.

“The dummy in the PAXCON protected room was unscathed,”

Says Alan Perryman, EMRTC’s Research Engineer and Test Specialist. He continues,

“A little dust kicked up, and the walls flexed and pounded like drums, but everything held up just fine. We at EMRTC are very impressed with the way the PAXCON protected room held up.”

Miraculously, the coating retained the wall, preventing it from major damage from the explosion. The coating would likely have prevented a fatal explosion, despite the magnitude of the blast. The company is the first and only of 27 other tested elastomeric polymers to pass all of the Air Force Laboratory Force Protection Branch bomb tests.

However, a question remains at large; Just how tough is it?

According to their web page, the coating can withstand tensile strengths up to 6,600 PSI. It can also resist tearing up to and exceeding 780 lbs per inch. Without a doubt, LineX is some tough stuff. The coating is also proven to be watertight, abrasion and impact resistant, and even fire resistant. During another test, the company was able to prove their product can easily outperform stainless steel and carbon fiber covers.

For ‘science’, here is another video depicting the immense strength the coating holds, preventing a water bottle from exploding.

The initial purpose of Line-X

Line-X is one of the several brands of highly durable spray-on coatings on the market. This spray provides a long lasting protective coating to, well anything. It is primarily marketed for use on truck beds but can be utilized for anything you can think of really. Notable applications for Line-X include bulletproof vests, bridges, boats and even the Pentagon. Its fantastic tensile strength means it can absorb kinetic energy from bullet fragments to explosive shrapnel.

The spray coatings can be applied to various surfaces from “metal, fiberglass, concrete, plastic, or wood” says Line-X. This coating is able to absorb impact and resist damage whilst remaining flexible and strong.

All of this is pretty amazing for something originally intended to protect the back of pickup trucks.

The manufacturer describes their products as “specialized, high-performance spray-on elastomeric coatings engineered for maximum durability and limitless application potential. Because LINE-X Protective Coatings form permanent bonds at the molecular level, they have excellent adhesion to a wide variety of surfaces. ”

“Thanks to research and product testing in both harsh real-world and laboratory conditions, LINE-X has found chemical combinations that result in specialized attributes and applications. Adaptable and resilient, some of these coatings are rated for fire safety and approved for use in potable water applications,” says Line-X.

Line-X is made of two chemicals, A and B. The main component of A Diphenylmethane-4,4′-diisocyanate or MDI. This compound is very reactive due to the reactive agents on both ends. Which is lovely. Component B is the polymer which acts as a plasticizer for the final application. Component B is mainly made up of alpha-(2-aminomethylethyl)-omega-(2-aminomethylethoxy)-poly[oxy(methyl-1,-2-ethanediyl)]. If you managed to read all that, we salute you.

Basically, with Line-X these two components are mixed together in a given ratio. They will react very rapidly and exothermically. The reaction takes seconds to form very long molecular threads. This provides both tensile strength and flexibility. The chains can be stretched out without breaking. All good, but simply mixing them in a bucket will just give you very strong blob, so how do they turn the product turn into a spray for easy application to surfaces?

The answer is to put them under very high pressures and temperatures, and force them together in a small space. This mixes the components together and allows you to fire them out of the end of a nozzle. The process of taking the separate components, pressurizing them, mixing them, spraying them and hitting the target surface all takes a fraction of a second. Neat!

The entire curing process takes about a day to complete but it becomes very strong in after a few minutes. As time goes on the polymerization process proceeds unabated until all reactants are depleted. Due to it being an exothermic reaction the surface is initially pretty hot to the touch but it does cool rapidly as the curing process continues.

All this talk of strength leads us to the obvious question: How effective would it be against bullets really? Well, let’s find out.


Line-X spray is applied at between 54 to 98 degrees Celsius using a high-pressure spray system. Final coats are generally pretty thin at around 0.635 centimeters but over a uniform surface. Thinner coats do follow the lines and contours of the target surface, which is preferable for vehicles of course. Line-X, when freshly applied, tends to have a “rough” surface that sparkles. Whilst aesthetically this might appeal to some, it could damage cargo and your precious knees. Reduction in “roughness” can, of course, be delivered but this will affect the glossy finish.

This might not be an issue, and rough surfaces will be more durable i.e. resistant to tearing.

What you need to know about Line-X spray

Line-X reviews should be easy to find but TundraHeadquarters is a pretty fair one. Their article makes a good comparison between main competitors. They have also provided some useful information if you’re seriously considering it.

1-As good as the spray product is, in theory, it only as good as the “install”. With any good “installers” or Line-X dealers, you will get the full protection that this product can provide.

2-All spray-on coatings will fade with time when exposed to sunlight. UV and time will win over any product hands down.

3-Related to point 2 above, Line-X spray will fade much faster than the rest of the paintwork on your vehicle or application. If you’re not too bothered about color matching then no worries but you have been warned.

4-Despite formulation varying between manufacturers like Rhino, Line-X is pretty much the same as the others.

5-Line-X dealers and other suppliers should provide lifetime warranties on their products.

6-Line-X cost should range between $400 and $800 dollars, give or take. Higher prices should include extras like color matching or UV protection.

7-You wouldn’t buy a vacuum cleaner from a dusty shop, so if the installer’s facilities are dirty you might want to go elsewhere.

8-As with anything in life, installers will try to sell you more than you need. Do you really need a product with high tensile strength, for instance? If you’ll only be using the truck bed for moving furniture once in a while a $800 install might be overkill. If you’ll be hauling equipment that can scrape the surface (shovels etc) you might actually want to invest in the hard, high-strength products like Line-X Premium.

[Image Source: LineXLondon]

Future applications of LineX could help protect buildings from natural disasters and even from devastating explosions. Planes could have an extra barrier of protection to similarly resist blasts. The applications are endless and could potentially save many lives. Future developments could even see the coating become an industry standard in construction and engineering.

Line-X certainly seems to live up to the hype. Now, what do I need bullet-proofing? Hmm, the possibilities are endless.

Sources: LineXTundraHeadquarters

Featured Image Source: LineX

SEE ALSO: How Engineers Can Protect Against Deadly Explosive Attacks


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