Overview
ISO 14632:2021 - Extruded sheets of polyethylene (PE‑HD): Requirements and test methods specifies requirements and test procedures for solid flat extruded sheets made from polyethylene high-density homopolymers (PE‑HD) without fillers or reinforcement. The standard applies to sheets (including rolled form) with nominal thicknesses from 0.5 mm to 40 mm and covers material composition, appearance, dimensional tolerances, mechanical/thermal properties and specified laboratory test methods.
Key Topics and Requirements
- Material: Sheets shall be made from PE‑HD extrusion compounds (additives such as stabilizers, processing aids and colorants permitted). Compounds of unknown identity are not allowed.
- Appearance: Sheets must be substantially free from bubbles, voids, cracks, visible impurities and surface defects; colorants must be homogeneously distributed.
- Dimensional tolerances
- Thickness tolerance given by formula: |Δh| ≤ ±(0.08 mm + 0.03 × h).
- Length and width tolerances are defined by nominal size ranges (small positive allowance, small negative allowance - agreed between parties when different).
- Rectangularity tolerance specified as difference between diagonal lengths; test methods and limits are in Annex A.
- Bow in rolled form: maximum 20 mm over 10 m.
- Mechanical and thermal properties (average values by sheet group): density, tensile stress/strain at yield, modulus of elasticity in tension, Charpy impact strength of notched specimens, and melt mass‑flow rate (MFR). The standard gives grouped requirement ranges (e.g., density bands 0.94–0.96 g/cm3, tensile stress at yield ≥15–≥25 MPa depending on group).
- Behaviour after heating / shrinkage: Maximum shrinkage limits for general and thermoforming applications are provided (specific % limits by nominal thickness).
- Test methods: Specimen preparation, conditioning and tests for density (ISO 1183), tensile (ISO 527), Charpy impact (ISO 179), MFR (ISO 1133), shrinkage, modulus and others are referenced and specified.
Applications and Users
ISO 14632:2021 is intended for:
- Manufacturers and extruders of PE‑HD extruded sheets for specifying product quality
- Quality laboratories performing test methods (density, MFR, tensile, Charpy, shrinkage)
- Product designers, thermoformers and fabricators who need defined material behaviour (e.g., shrinkage limits for thermoforming)
- Procurement and specification writers requiring consistent dimensional tolerances and mechanical performance
Practical benefits include standardized acceptance criteria, clearer supplier-buyer agreements, and reduced risk of forming/fabrication defects when using extruded PE‑HD sheets.
Related Standards
Normative references include (selection):
Keywords: ISO 14632:2021, PE‑HD, extruded polyethylene sheets, test methods, dimensional tolerances, MFR, Charpy impact, tensile strength, shrinkage, thermoforming.