ISO 24026-2:2020

Overview - ISO 24026-2:2020 (PMMA test specimens & property determination)

ISO 24026-2:2020 specifies methods for the preparation of test specimens and the determination of properties of poly(methyl methacrylate) (PMMA) moulding and extrusion materials. It defines handling and conditioning requirements for raw material and specimens, prescribes injection-moulding conditions to obtain reproducible results, and lists the test methods appropriate to characterize PMMA materials. This document complements the designation system in ISO 24026-1 and references general test practices in ISO 10350-1.

Key topics and technical requirements

• Specimen preparation: Specimens shall be prepared by injection moulding in accordance with ISO 294-1 using the standardised processing parameters in this part.
• Material treatment before moulding: Moisture content must not exceed 0.05% by mass; dry the material if necessary following manufacturer instructions.
• Melt and mould temperatures:
  • Melt temperature can be derived from the MFR code-number (table values 270–220 °C) or from VST and VN code-numbers using the formula T = TVS + 130 + a. Melt must be held within ±3 °C.
  • Mould temperature is Tvst − 40 °C and must be kept within ±3 °C.
• Processing parameters:
  • Average melt velocity: 200 mm/s ± 100 mm/s
  • Cooling time: 50 s ± 5 s
  • Hold pressure: set to produce specimens with only very slight sink marks
• Conditioning of specimens:
  • Oven conditioning: 16 h at (VST code-number − 25) °C (±3 °C)
  • Followed by at least 24 h at 23 ± 2 °C and 50 ± 10% RH (exceptions for specific thermal/other tests)
• Test methods and properties:
  • Properties selected from ISO 10350-1 and other standards: MFR/MVR, viscosity number, tensile and flexural modulus/strength, Charpy/Izod impact, Vicat softening temperature, temperature of deflection under load, water absorption, density, hardness, refractive index, light transmission, effect of liquid chemicals, dynamic mechanical properties, etc.
• Standard atmosphere: Tests performed at 23 ± 2 °C and 50 ± 10% RH unless stated otherwise.

Applications and users

ISO 24026-2 is used by:

• Materials scientists and polymer laboratories for material characterization and data comparability.
• Manufacturers of PMMA compounds and finished parts for quality control, product specification, and R&D.
• Test laboratories performing certification or comparative studies of PMMA moulding and extrusion materials.
• Product designers and specifiers who require reliable property data (mechanical, thermal, optical) for component selection.

Practical benefits include consistent test specimen production, reproducible property data for material selection, and alignment with international PMMA designation practices.

Related standards (selection)

• ISO 24026-1 - PMMA designation system
• ISO 10350-1 - Acquisition and presentation of single-point data
• ISO 294-1 - Injection moulding of test specimens
• ISO 1133-1, ISO 527-2, ISO 1183-1, ISO 75-2, ISO 306 - referenced test methods

Keywords: ISO 24026-2, PMMA, poly(methyl methacrylate), test specimens, moulding and extrusion materials, specimen conditioning, melt temperature, MFR, VST, material testing.