When engineers compare heat-resistant fabrics, the fiber tends to get most of the attention. Fiberglass, silica, basalt, ceramic, and other high-temperature fibers each have their own thermal limits and physical properties, so the base material is an obvious place to start.
But the base fiber is only part of how a finished textile performs. Coatings give engineers another way to tailor that material for the conditions it will face once it’s installed, from abrasion and handling to contaminants and different types of heat exposure. Two textiles made from similar fibers can behave very differently once they’re installed around a hose, wrapped over process piping, fabricated into a gasket, or used as a barrier near hot equipment.
That’s because the finished material may need to do much more than tolerate temperature. It may need to withstand repeated handling, resist abrasion against nearby components, hold its shape during installation, shed contaminants, or deal with radiant heat and molten splash.
Coatings can change the performance and working characteristics of a high-temperature fabric without changing the base fiber and underlying textile construction.1
Coatings have long been used to tailor properties such as flame resistance, thermal stability, durability, and water repellency, and current research continues to study how different coating formulations and application methods influence those properties.¹
Depending on the coating and application, that can mean better abrasion resistance, more rigidity, greater flexibility, improved resistance to oils or other contaminants, less fraying, different sealing characteristics, or another layer of protection between the textile and its surroundings.
Davlyn Group applies a range of coatings to our technical textiles, including silicone elastomer, vermiculite, PTFE, graphite, acrylic saturant, reflective foil, rubber, and other custom treatments. Each one serves a different purpose, so selecting a coating starts with understanding what the finished textile will actually be up against during service.
A Temperature Rating Doesn’t Tell You How a Textile Will Behave
Maximum operating temperature is an important part of selecting thermal protection materials, but it doesn’t describe everything the material will experience from heat exposure once it’s put to work. That broader operating environment is also where a coating can make a meaningful difference.
Think about a protective sleeve routed through a piece of industrial equipment. The sleeve could rub against a bracket every time the equipment vibrates. An installer may have to pull several feet of it over a hose assembly. Hydraulic fluid or oil could occasionally reach the surface. And the material could also be removed and replaced during maintenance.
Those conditions can call for properties the base textile alone doesn’t provide. A coating may add abrasion resistance, change the material’s rigidity or flexibility, or provide surface protection from oils and other contaminants.
A fabric that comfortably handles the thermal conditions can still be a poor fit if it frays badly during installation, wears through from repeated contact, absorbs contaminants, or becomes difficult to work with in the finished assembly.
Davlyn Group accounts for many of these factors when developing custom textile products, including thermal resistance, weight and density, flexibility, shop and field workability, abrasion resistance, durability, and environmental requirements.
The coating becomes part of that overall material specification. It can modify the surface or handling properties of a textile that already has the right basic fiber, weave, thickness, or geometry for the application.
Abrasion Can Be Just as Important as Heat
High-temperature textiles usually end up in places where there’s plenty of physical contact. Sleeves can rub against hoses or nearby hardware. Tapes are pulled tightly around components. Gaskets are compressed between surfaces. Blankets and curtains may be folded, moved, stored, and put back into use.
All of that creates opportunities for wear, but a coating can help protect the textile surface from some of that day-to-day punishment.
Davlyn Group’s vermiculite-coated fiberglass sleeves are a good example. The vermiculite treatment adds rigidity and abrasive strength and reduces the likelihood of fraying at the ends. For long sleeve runs, that extra rigidity can also make the material easier to feed over a hose or cable during installation. Davlyn Group also offers vermiculite coatings on silica sleeves specifically to increase abrasion resistance.
There are countless applications where installation or equipment movement might damage an otherwise suitable textile. A very high thermal rating has limited value if the material gets torn up mechanically before temperature becomes the main concern.
Coatings Can Change How a Material Handles During Installation
Installation doesn’t always get much attention on a material data sheet, but it can have a big effect on the finished result.
Some heat-resistant materials have to bend tightly around irregular shapes. Others need enough body to push or pull over long sections of a hose. A gasket material may need to stay manageable during cutting and assembly. And a protective textile installed inside crowded equipment might need to tolerate bending, folding, and contact with surrounding hardware.
Coatings can change those working characteristics.
A saturant can reduce fraying and increase abrasion resistance. A flexible elastomeric coating can give the surface a different feel and provide protection to the fibers underneath. Vermiculite can add rigidity where a looser textile would be difficult to install.
There isn’t one universally desirable level of stiffness or flexibility. A coating that makes one product easier to install could make another product harder to wrap around a tight radius. So engineers have to consider the geometry of the finished component along with the textile’s properties on paper.
This is one reason coating selection works best as part of the complete material specification instead of as an add-on at the end.
Protection From Oils, Fluids & Other Contaminants
Industrial textiles don’t operate in clean laboratory environments. Hoses leak, lubricants get sprayed, dust collects. Process materials reach nearby components.
Maintenance work also introduces cleaners, oils, and other substances that weren’t necessarily part of the primary thermal process. A suitable coating can provide useful surface protection.
Davlyn Group’s Silco Sleeve® Firesleeve, for example, combines a fiberglass substrate with a fully cured silicone elastomer coating. In addition to heat and flame protection, the finished sleeve is resistant to hydraulic fluids, lubricating oils, and fuels. It’s commonly used around pipes, hoses, wires, and cables in industrial and aerospace applications.
Silco Tape® uses a similar idea in a different form. Its silicone elastomer coating protects the underlying fiberglass tape from molten metal splash, oils, and other contaminants in addition to contributing to its thermal performance.
That doesn’t mean silicone is automatically the right coating whenever fluids are present. The exact chemicals, concentration, frequency of exposure, temperature, and cleaning process still need to be considered. The larger point is that the surrounding environment matters just as much as the heat source.
Radiant Heat & Molten Splash Create Different Demands
A textile sitting near a hot surface doesn’t always face the same problem as one exposed to sparks or molten metal.
Radiant heat transfers energy without direct contact, which means hoses, cables, personnel, and equipment can need protection even when they aren’t touching the hot component. In other applications, the bigger concern may be intermittent contact with sparks, weld splatter, or molten splash.
Certain coatings can give technical textiles properties better suited to specific types of exposure.
Davlyn Group’s silicone-coated fiberglass fire blankets, for example, are designed for heat, sparks, flame, and molten splash protection in applications such as welding curtains, personnel protection, and equipment shielding. Reflective foil is another available coating option in our high-temperature textile line and can be specified for certain constructions where reflective surface performance is useful.
When comparing options for industrial thermal insulation and protection, keep in mind that “high heat” can describe very different operating conditions, and the coating needs to match the way thermal energy actually reaches the material.
What Engineers Should Consider Before Specifying a Coated Textile
A good coating specification starts with the conditions the finished material will face. The base fiber establishes many of the textile’s core properties, while the coating can change how that material handles abrasion, installation, contaminants, and other demands within the application.
When evaluating a coated textile, engineers should consider:
- Thermal conditions: Normal operating temperature, peak exposure, duration of exposure, and whether the material will face conducted heat, radiant heat, flame, sparks, or molten splash.
- Physical demands: Abrasion, repeated flexing, contact with nearby equipment, tight bends, long installation runs, and removal during maintenance.
- Environmental exposure: Oils, hydraulic fluids, fuels, moisture, solvents, process chemicals, dust, and cleaning agents that could reach the material.
- Fabrication and installation: Cutting, sewing, wrapping, compressing, fastening, and other handling requirements that affect how the textile works within the finished assembly.
- Changes to the finished material: Coatings can affect weight, thickness, flexibility, handling, surface characteristics, and temperature capability, so the coated construction should be evaluated as a whole rather than by the base fabric alone.
Davlyn Group offers silicone elastomer, vermiculite, PTFE, graphite, acrylic saturant, reflective foil, rubber, and custom coating options for a broad range of technical textile products. Our engineers and material scientists can help match the base material, coating, and construction to the operating conditions and performance requirements of your application.
If you’re evaluating heat-resistant fabric or other thermal protection materials for a new design, contact Davlyn Group to discuss your application.
Frequently Asked Questions
What is the difference between silicone-coated and PTFE-coated fiberglass?
Both use fiberglass as the base textile, but the coatings give the finished material different surface properties. Silicone-coated fiberglass is commonly used when flexibility, grip, abrasion resistance, and protection from moisture or oils are important. PTFE coatings are often selected for lower surface friction, release properties, and chemical resistance. The right choice depends on the temperature range, exposure conditions, movement, and surface characteristics required by the application.
Is silicone-coated fiberglass waterproof?
Silicone-coated fiberglass is generally resistant to water and moisture, but “waterproof” depends on the specific construction. Coating coverage, seams, closures, penetrations, and cut edges can all affect how a finished product handles moisture. For applications where water exposure is an important requirement, engineers should review the specifications for the complete fabricated component rather than assuming the coating alone makes it waterproof.
Can coated fiberglass fabric be cut or sewn?
Yes, many coated fiberglass constructions can be cut, sewn, stitched, folded, or otherwise fabricated into finished components. Davlyn Group offers cutting, sewing, stitching, folding, and other custom fabrication capabilities. The coating and textile construction can affect edge fraying, flexibility, handling, and the fabrication method used, so those requirements should be considered when designing the finished part.
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