Coatings

NAT has an extensive portfolio of proprietary technologies and expertise in coating formulations. We specialize in high-performance sol-gel organic-inorganic hybrid products designed to meet the stringent requirements of aerospace and military applications, as well as addressing general technological challenges. These activities have been amply funded by branches of the Department of Defense, Department of Energy, and the National Science Foundation.

NAT’s coating technology services include polymer chemistry, conceptual design of new formulations to meet customer specifications, troubleshooting existing technologies, and evaluating and recommending appropriate coating solutions.

Overview of NAT Coating Technologies

Weatherable, Transparent, Scratch-and-Corrosion Resistant Coating Based on Si-Ti Ceramers

Selected Technical Parameters:

When coated onto Melinex 454 (Polyethylene terephthalate, PET) substrates and cured, the coating demonstrated:

  • No cracking, voids, bubbles or delamination
  • Excellent flexibility (no evidence of cracking) when tested per ASTM D522
  • 5B rating on dry adhesion as tested per ASTM D3359
  • 5B rating on wet adhesion per ASTM D3359 (after 4 hours DI water boil)
  • Very high maximum use/operating temperature of 190°C
  • No loss of adhesion or cracking in thermal cycling & humidity/freeze cycling
  • Excellent dielectric properties per ASTM D149 (passed all testing)
  • Minimal color change (delta a*, delta b* = +0.06, +0.26) during 500 hours of damp heat exposure (85%RH, 85oC)
  • Coated PET showed a reduced haze (ca. 0.75% decrease) compared to the (uncoated) PET control during damp heat testing
  • Excellent adhesion (5B rating, ASTM D3359) after 500 hours in damp heat
  • Minimal color change (delta a*, delta b* = +0.13, -0.34) during 500 hours in weatherometer (65oC, 1 sun, Xenon Arc)
  • Coated PET showed significantly reduced haze (~1.5% reduction) compared to the (uncoated) PET control during weatherometer testing
  • Excellent adhesion (5B rating, ASTM D3359) after 500 hours in weatherometer o Coated PET showed an increase in transmission (0.4 to 1.2%) when compared to the (uncoated) PET control
  • Capability to be applied by both flow coating and solution casting o A minimum 6 month coating solution shelf life
  • Scratch hardness values [per ASTM D3363] between 2H and 3H

Additional in house testing of these coatings has demonstrated the following properties:

  • Protect Polycarbonate substrates with a range of properties similar to PET
  • Protects 6061 aluminum, steel, and copper from corrosion in a salt spray
  • environment for periods in excess of 300 hours (per ASTM B117)
  • Abrasion resistance is greater than 100 L/mil (ASTM D968, falling sand)
  • Low VOCs, less than < 250 g/L (mainly alcohols)
  • 5B rating on adhesion (ASTM D3359) after exposure to liquid N2