ISO 4664-3:2021

Overview

ISO 4664-3:2021 - Rubber, vulcanized or thermoplastic - Determination of dynamic properties - Part 3: Glass transition temperature (Tg) specifies a standardized method to determine the glass transition temperature (Tg) of vulcanized and thermoplastic rubbers in the hardness range 30–80 IRHD. The method uses a temperature sweep under controlled sinusoidal deformation (dynamic mechanical testing) and identifies Tg as the peak in the tan δ (loss factor) versus temperature curve. Tg obtained by this dynamic method is intended as a guideline to the material’s service temperature.

Key topics and requirements

• Measurement principle: Dynamic mechanical analysis (DMA)-style temperature ramp with sinusoidal deformation; Tg = temperature at maximum tan δ.
• Material range: Vulcanized or thermoplastic rubbers, hardness 30–80 IRHD.
• Test modes & specimens:
  • Compression cylinder: 10 mm height × 10 mm diameter (preferred).
  • Tension strip: preferred dimensions 25 mm length, 10 mm width, 2.0 ± 0.2 mm thickness with 10 mm test length.
  • Shear: sandwich construction with rubber elements bonded to metal cylinders.
• Apparatus performance:
  • Force readout accuracy ±1.0%.
  • Loss factor (tan δ) accuracy ±5% or ±0.02 (whichever smaller).
  • Sinusoidal wave with