Overview
EN ISO 6427:2025 - Plastics - Determination of matter extractable by organic solvents (conventional methods) (ISO 6427:2025) specifies laboratory methods to determine components in plastics that are extractable by hot organic solvents near their boiling points, including a defined cold‑extraction procedure. Extractable matter can include monomers, oligomers, polymers, plasticizers, stabilizers and other additives. The standard is intended for general plastics testing (not for food or drinking water contact applications) and supersedes EN ISO 6427:2014.
Key topics and requirements
- Scope: Methods for hot-solvent extraction and a special cold-extraction method; not intended for migration tests and excluded from food/drinking water contact materials.
- Reagents & materials: Use of analytical‑reagent grade extraction liquids (selected per material), anti‑bumping granules and pre‑extracted glass wool.
- Apparatus: Describes suitable extraction equipment such as Soxhlet and Twisselmann extractors, reflux condensers, explosion‑proof heating, rotary evaporator or Vigreux distillation column, vacuum oven (maintain temperature within ±2 K), precision balance (0.1 mg), mills and sieves.
- Sample preparation: Procedures for reducing and sieving samples (avoiding overheating), choice of extraction containers (cellulose thimbles, metal wire baskets, glass‑filter crucibles) and cautions about container effects on results.
- Procedure and expression of results: Steps to carry out extractions, concentrate and dry extracts, and report extractable matter as percentage; clauses on precision and test reporting are included.
- Operational flexibility: For plastics not listed in the normative Table 1, operating conditions should be agreed between interested parties; tolerances for test parameters have been clarified in this edition.
Practical applications and users
- Quality control and acceptance testing for raw polymer batches, additives and finished plastic articles.
- Comparative evaluation of plastic formulations to monitor plasticizers, residual monomers or low‑molecular‑weight oligomers.
- Research labs and materials development to assess formulation changes that influence mechanical, thermal or chemical behavior.
- Primary users: polymer manufacturers, independent testing laboratories, materials engineers, quality assurance teams and regulatory bodies (except for food/drinking water migration testing).
Related standards
This document references and aligns with related ISO standards used in laboratory set‑ups and specific tests:
Keywords: EN ISO 6427:2025, ISO 6427:2025, plastics extractable matter, Soxhlet extraction, cold‑extraction, extractable components, plastic testing standards.
