Impregnated Grades

In addition to virgin PTFE products, BTR offers a wide range of compounded products as well.
Among these compounds, which are manufactured from selected polymers and special high-purity fillers, end users are able to find the right answer to their requirements of application.

The following table shows the way each filler affects physical and mechanical properties.
Combinations of two or more fillers (not considered in the table) allow a large number of compounds. Thus the resulting combined properties offer a variety of applications. 

PTFE impregnated grades filler affects


Filler

Property

Most common applications

Glass
  • Enhanced wear resistance.
  • Enhanced chemical resistance (except for alkali and hydrofluoric acid).
  • Valve seats, seals, bearings, requested to resist sliding and chemicals.
  • Suitable for bearings working at low PV values.
Graphite
  • Extremely low coefficient of friction.
  • Fairly good compressive strength.
  • Good wear resistance.
  • Bearings for high speed on fairly hard surface.
Carbon
  • Good thermal conductivity.
  • Good resistance to deformation.
  • Valve seats.
  • Bearings for high speed and when fast dissipation of electric charges is needed.
  • Elastic bands for non-lubricated compressors.
Molybdenum disulphide
  • Enhanced non-stick properties.
  • Low static coefficient of friction.
  • Fairly good resistance to deformation.
  • Guide bands.
  • Details needing good resistivity.
Bronze
  • Enhanced compressive strength.
  • Good wear resistance and high thermal conductivity.
  • Anti-extrusion rings.
  • Non-lubricated bearings for high speed on not hard surface.

 Table: shows PTFE impregnated grades filler affects

Properties - 25% Carbon Impregnated

Property Unit of measure Value
Tensile Strength Mpa 15-20
Elongation at Break % 150-200
Modulus of Elasticity MPa -
Impact Strength kj/m² -
Compressive Strength MPa 7-9
Shear Strength MPa -
Shore Hardness D Scale 60-65
Co-efficient of Friction μ 0.13
Water Absorption @ 23 Deg C % 0.03
Service Temperature Intermittent ᵒC 310
Service Temperature Continuous ᵒC 260
Melting point ᵒC 335
Thermal Conductivity W/m.ᵒC 0.54
Dielectric Strength kV/mm 2
Volume Resistivity Ω.cm 10⁴
Surface Resistivity 10⁷
Arc Resistance Sec -

Properties - 25% Glass Impregnated

Property Unit of measure Value
Tensile Strength Mpa 14-21
Elongation at Break % 230-270
Modulus of Elasticity MPa 3100
Impact Strength kj/m² 8.5
Compressive Strength MPa 8-9
Shear Strength MPa -
Shore Hardness D Scale 62-67
Co-efficient of Friction μ 0.13
Water Absorption @ 23 Deg C % 0.02
Service Temperature Intermittent ᵒC 310
Service Temperature Continuous ᵒC 260
Melting point ᵒC 335
Thermal Conductivity W/m.ᵒC 0.46
Dielectric Strength kV/mm 13
Volume Resistivity Ω.cm 10¹⁵
Surface Resistivity 10¹⁶
Arc Resistance Sec -

Properties - 60% Bronze Impregnated

Property Unit of measure Value
Tensile Strength Mpa 17-23
Elongation at Break % 100-160
Modulus of Elasticity MPa -
Impact Strength kj/m² -
Compressive Strength MPa 10-11
Shear Strength MPa -
Shore Hardness D Scale 65-70
Co-efficient of Friction μ 0.13
Water Absorption @ 23 Deg C % 0.05
Service Temperature Intermittent ᵒC 310
Service Temperature Continuous ᵒC 260
Melting point ᵒC 335
Thermal Conductivity W/m.ᵒC 0.77
Dielectric Strength kV/mm 0
Volume Resistivity Ω.cm 10⁷
Surface Resistivity 10⁹
Arc Resistance Sec -

Properties - 15% Graphite Impregnated

Property Unit of measure Value
Tensile Strength Mpa 15-20
Elongation at Break % 170-250
Modulus of Elasticity MPa -
Impact Strength kj/m² -
Compressive Strength MPa 6.5-7.5
Shear Strength MPa -
Shore Hardness D Scale 55-60
Co-efficient of Friction μ 0.07
Water Absorption @ 23 Deg C % 0.03
Service Temperature Intermittent ᵒC 310
Service Temperature Continuous ᵒC 260
Melting point ᵒC 335
Thermal Conductivity W/m.ᵒC 0.52
Dielectric Strength kV/mm 2
Volume Resistivity Ω.cm 10⁴
Surface Resistivity 10⁷
Arc Resistance Sec -