SIST EN ISO 21306-2:2019 PDF

Overview

EN ISO 21306-2:2019 specifies standardized methods for the preparation of test specimens and the determination of material properties of unplasticized poly(vinyl chloride) (PVC‑U) used for moulding and extrusion. It defines how to handle, precondition and process PVC‑U test material so laboratory results are reproducible and comparable. This part is intended to be used together with ISO 21306‑1 (designation and specification basis) and the presentation rules in ISO 10350‑1.

Key topics and technical requirements

• Specimen preparation method: Test specimens shall be prepared by compression moulding (code letter “Q”). If stamping or machining is used, procedures and dimensions must follow referenced standards.
• Pre-treatment before moulding: Material shall be preplasticized on a two‑roll mill under defined conditions (e.g., mill-roll surface temperature ~+90 °C, milling time ~5 ±1 min - see standard tables for full values).
• Compression moulding conditions: Compression‑moulded sheets are produced per ISO 293 with specified moulding temperatures (≈+100 °C), cooling rates, pressures and times to control thermal history and residual stresses.
• Specimen finishing: Test specimens are machined from moulded sheets in accordance with ISO 2818 or stamped from sheets.
• Conditioning: Specimens must be conditioned per ISO 291 (normally at 23 °C ±2 °C and 50 % ±5 % RH) for at least 16 hours before testing (electrical tests: 24 hours).
• Data presentation and traceability: Results are to be reported as required in ISO 10350‑1 and linked to ISO 21306‑1 property designation.
• Important cautions: Values depend on specimen size, moulding compound, shape, anisotropy, gating and processing (temperature, pressure, injection rate) and any post‑treatment (annealing, conditioning). Thermal history and internal stresses strongly affect mechanical and thermal properties (and resistance to environmental stress cracking), but have less effect on electrical properties.

Applications and users

• PVC‑U compound manufacturers and formulators - for material specification and quality control.
• Test laboratories and certification bodies - to produce reproducible mechanical, thermal and electrical data.
• Product designers and OEMs using PVC‑U for moulded or extruded parts - to compare materials and ensure compliance with specifications.
• Regulatory authorities and standards committees - to harmonize test practice and material declarations.

Related standards (examples)

• ISO 21306‑1 - Designation system and basis for specifications
• ISO 10350‑1 - Data presentation for moulding materials
• ISO 293 - Compression moulding of thermoplastic test specimens
• ISO 2818 - Preparation of test specimens by machining
• ISO 291 - Standard atmospheres for conditioning and testing
• IEC/IEC 62631 series and IEC 60243‑1 - Relevant electrical test methods

Keywords: EN ISO 21306-2:2019, PVC‑U test specimens, compression moulding, specimen conditioning, PVC-U properties, ISO 21306, material testing, PVC extrusion and moulding materials.