Glass Fiber-Filled PTFE

Glass fiber increases the wear and creep resistance of PTFE. It is the most common PTFE filler. Glass fiber-filled PTFE materials can be used in oxidizing environments, but be aware that glass fiber reacts with HF and strong bases.

Glass fiber-filled PTFE materials have a slightly higher coefficient of friction but better extrusion resistance than Glass fiber/Moly-filled PTFE materials. They are typically used in seal components for dynamic applications. They also prefer a lubricated environment and are used to seal against steel, stainless steel, and chromium-plated surfaces.

PBY Material Codes:

PB10302 - 15% Glass Fiber-Filled PTFE

PB10305 - 25% Glass Fiber-Filled PTFE

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Glass Fiber-Filled PTFE Spec. Summary

Property Test Method Units 15 Glass Fiber 25 Glass Fiber
Color - - White White
Specific Gravity ASTM D792 - 2.150 - 2.250 2.150 - 2.250
Hardness Shore D ASTM D2240 - 60 - 70 60 - 70
Tensile Strength, min. ASTM D4745 PSI [MPa] 2,840 [19.6] 2,270 [15.7]
Elongation at Break, min. ASTM D4745 % 220 180
Second Melt Peak Temp. ASTM D3418 °F [°C] 621 [327] 621 [327]
Glass Transition Temp. ASTM D3418 °F [°C] -143 [-97]; 246 [119] -143 [-97]; 246 [119]

Material Available In:

Glass Fiber-Filled PTFE Rods

Glass Fiber-Filled PTFE Tubes

Glass Fiber-Filled PTFE Sheets

Glass Fiber-Filled PTFE Material Properties

  • Increases wear and creep resistance

  • Chemically Inert (Exceptions in HF and Strong Bases)

  • Performs well in oxidizing environments

Typical Applications for Glass Fiber-Filled PTFE

  • Wear Pads

  • Piston rings

  • Cookware coatings and rotating platforms

  • Containers and pipelines for chemicals

  • Machinery lubricant

Glass Fiber-Filled PTFE Requirements

PB10302 meets ASTM D4547 Type I Grade I requirements.

PB10305 meets ASTM D4745 Type I Grade 2 and AMS 3678/4 requirements.

Glass Fiber-Filled PTFE Material Data Sheet Downloads

PB10302 - Material Data Sheet

PB10305 - Material Data Sheet

Glass Fiber-Filled PTFE Spec. Compliance



  • Wypych, George. Handbook of Polymers. 2nd Ed., ChemTec/Publishing, 2016.
  • Ebnesjjad, Sina. Fluoroplastics Vol1 & Vol2. 2nd Ed., Elsevier Inc., 2015.
  • Aerospace Materials Specifications for PTFE materials (AMS3678)
  • American Society for Testing and Materials (ASTM) Standards