How to Choose the Right Phenolic Resin Grade: PF2 / PF5 / PF7

ISO, DIN, GB standards — understanding the global grading system and practical selection tips

Phenolic resin grades can be confusing — ISO, DIN, GB, and ASTM each have their own naming systems. This article maps these systems together so you can quickly identify the right grade for your application.

Global Phenolic Resin Classification Systems

Grade
ISO
DIN (German)
China GB
Typical Use
PF2
PF 2060
Durite BC-12
4012
General purpose, low cost
PF5
PF 2065
Durite HF-1
4065
High mechanical strength, bearings
PF7
PF 2070
Durite N-1
4070
High temperature, electrical insulation
Electrical Grade
PF 2061
Novotext E
4013
Switches, insulation parts

Four Key Performance Indicators

Flexural Strength
PF5: >100 MPa, PF7: >80 MPa
Heat Distortion
PF7 reaches 200-210C
Arc Resistance
Electrical grade: >180 sec
Water Absorption
All grades: <0.15%

Practical Selection Guide

High Temperature Applications (>150C)

Choose PF7 or equivalent high-heat grade. Standard PF2 will soften, discolor, and crack under sustained high heat.

Bearings / Wear Parts

Choose PF5 or mineral-filled grades. Pure phenolic has high friction coefficient — graphite or copper-filled compounds wear better.

Electrical Insulation Parts

Choose electrical grade phenolic resin (equivalent to GB 4013), with arc resistance and low water absorption requirements.

Food Contact

Verify FDA certification. Non-certified materials cannot be used in food-contact parts.

Common Selection Mistakes

  • Choosing by price alone: PF2 is cheap, but using it in high-temperature conditions leads to quick failure and higher total cost.
  • Ignoring fillers: PF5 with wood flour vs. glass fiber reinforcement have vastly different properties.
  • Skipping chemical resistance check: Phenolic resin is sensitive to strong alkalis and oxidizers.
Not sure which grade to use?

Send your working conditions (temperature, pressure, medium) — I'll recommend the right grade.

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