EN ISO 21304-2:2021

Plastics - Ultra-high-molecular-weight polyethylene (PE-UHMW) moulding and extrusion materials - Part 2: Preparation of test specimens and determination of properties (ISO 21304-2:2021)

This document specifies the methods of preparation of test specimens and the test methods to be used in determining the properties of PE-UHMW moulding and extrusion materials. It gives the requirements for handling test material and for conditioning both the test material before moulding and the specimens before testing.
This document gives the procedures and conditions for the preparation of test specimens and procedures for measuring properties of the materials from which these specimens are made. Properties and test methods which are suitable and necessary to characterize PE-UHMW moulding and extrusion materials are listed.
The properties have been selected from the general test methods in ISO 10350-1. Other test methods in wide use for or of particular significance to these moulding and extrusion materials are also included in this document, as are the designatory properties specified in ISO 21304-1. This document specifies the materials with MFR less than 0,1 g/10 min at 190 °C /21,6 kg based on ISO 17855-1.
The methods of preparation and conditioning, the specimen dimensions and the test procedures specified in this document are used in order to obtain reproducible and comparable test results. Values determined will not necessarily be identical to those obtained using specimens of different dimensions or prepared using different procedures.

Kunststoffe - Ultrahochmolekulare Polyethylen (PE-UHMW)-Formmassen - Teil 2: Herstellung von Probekörpern und Bestimmung von Eigenschaften (ISO 21304-2:2021)

Dieses Dokument legt die Verfahren zur Herstellung von Probekörpern und die zur Bestimmung der Eigenschaften von PE UHMW Formmassen anzuwendenden Prüfverfahren fest. Es enthält die Anforderungen an die Behandlung des Probenmaterials und an das Konditionieren sowohl des Probenmaterials vor der Herstellung als auch der Probekörper vor der Prüfung.
Dieses Dokument enthält die Verfahren und Bedingungen für die Herstellung der Probekörper und Verfahren zur Bestimmung der Eigenschaften der Werkstoffe, aus der die Probekörper hergestellt werden. Eigenschaften und Prüfverfahren, die anwendbar und notwendig sind, um PE UHMW Formmassen zu charakterisieren, sind aufgelistet.
Die Eigenschaften wurden aus den in ISO 10350 1 angegebenen allgemeinen Prüfverfahren ausgewählt. Andere weithin gebräuchliche Prüfverfahren oder solche von besonderer Bedeutung für diese Formmassen sind, wie auch die in ISO 21304 1 festgelegten kennzeichnenden Eigenschaften, ebenfalls in diesem Dokument enthalten. Dieses Dokument legt die Werkstoffe mit einer MFR (Schmelze-Massefließrate, en: melt mass-flow rate) von weniger als 0,1 g/10 min bei 190 °C/21,6 kg nach ISO 17855 1 fest.
Die in diesem Dokument festgelegten Verfahren für die Herstellung und Konditionierung, Probekörpermaße und Prüfverfahren werden angewendet, um reproduzierbare und vergleichbare Prüfergebnisse zu erhalten. Die ermittelten Werte sind nicht notwendigerweise mit denen identisch, die bei Anwendung von Probekörpern anderer Maße oder solchen, die mit einem anderen Verfahren hergestellt wurden, erhalten werden.

Plastiques - Matériaux à base de polyéthylène à très haute masse moléculaire (PE-UHMW) pour moulage et extrusion - Partie 2: Préparation des éprouvettes et détermination des propriétés (ISO 21304-2:2021)

Le présent document spécifie les méthodes de préparation des éprouvettes et les méthodes d'essai qui doivent être utilisées pour la détermination des propriétés des matériaux pour moulage et extrusion à base de PE-UHMW. Il donne les exigences relatives à la manipulation du matériau d'essai et au conditionnement du matériau d'essai avant moulage et des éprouvettes avant essai.
Le présent document donne les modes opératoires et les conditions nécessaires à la préparation des éprouvettes, ainsi que les modes opératoires de mesure des propriétés des matériaux à partir desquels les éprouvettes sont obtenues. Les propriétés et méthodes d'essai qui sont utiles et nécessaires pour caractériser les matériaux pour moulage et extrusion à base de PE-UHMW sont énumérées.
Les propriétés ont été sélectionnées parmi les méthodes d'essai générales de l'ISO 10350‑1. D'autres méthodes d'essai largement utilisées ou qui revêtent une importance particulière pour ces matériaux pour moulage et extrusion sont aussi incluses dans le présent document; c'est le cas des propriétés de désignation spécifiées dans l'ISO 21304‑1. Le présent document spécifie les matériaux avec un MFR inférieur à 0,1 g/10 min à 190 °C /21,6 kg selon l'ISO 17855‑1.
Les méthodes de préparation et de conditionnement, les dimensions d'éprouvette ainsi que les modes opératoires d'essai spécifiés dans le présent document sont utilisés dans le but d'obtenir des résultats d'essai reproductibles et comparables. Les valeurs déterminées ne seront pas nécessairement identiques à celles obtenues en utilisant des éprouvettes de dimensions différentes ou préparées selon des modes opératoires différents.

Polimerni materiali - Materiali na osnovi polietilena z ultra visoko molsko maso (PE-UHMW) za oblikovanje in ekstrudiranje - 2. del: Priprava preskušancev in ugotavljanje lastnosti (ISO 21304-2:2021)

General Information

• Status: Published
• Publication Date: 19-Jan-2021
• Withdrawal Date: 30-Jul-2021
• ICS: 83.080.20 - Thermoplastic materials
• Technical Committee: CEN/TC 249 - Plastics
• Drafting Committee: CEN/TC 249 - Plastics
• Current Stage: 6060 - Definitive text made available (DAV) - Publishing
• Start Date: 20-Jan-2021
• Completion Date: 20-Jan-2021
• Ref Project: SIST EN ISO 21304-2:2021 - Plastics - Ultra-high-molecular-weight polyethylene (PE-UHMW) moulding and extrusion materials - Part 2: Preparation of test specimens and determination of properties (ISO 21304-2:2021)

Relations

• Replaces: EN ISO 11542-2:1998/AC:2008 - Plastics - Ultra-high-molecular-weight polyethylene (PE-UHMW) moulding and extrusion materials - Part 2: Preparation of test specimens and determination of properties (ISO 11542-2:1998/Cor 1:2007)
• Effective Date: 23-Jan-2019
• Replaces: EN ISO 11542-2:1998 - Plastics - Ultra-high-molecular-weight polyethylene (PE-UHMW) moulding and extrusion materials - Part 2: Preparation of test specimens and determination of properties (ISO 11542-2:1998)
• Effective Date: 23-Jan-2019

Overview

EN ISO 21304-2:2021 - Plastics - Ultra-high-molecular-weight polyethylene (PE‑UHMW) moulding and extrusion materials - Part 2 - specifies how to prepare test specimens and determine material properties for PE‑UHMW used in moulding and extrusion. The standard sets out handling, conditioning and specimen-preparation procedures designed to deliver reproducible, comparable test results for PE‑UHMW materials (specified for materials with MFR < 0,1 g/10 min at 190 °C / 21,6 kg).

Key Topics and Requirements

• Scope and applicability: Methods apply to PE‑UHMW moulding and extrusion materials; chosen properties align with ISO 10350-1 and ISO 21304-1 designation properties.
• Material treatment before moulding: Requirements for handling and any pre-processing conditioning of bulk material prior to specimen production.
• Specimen preparation: Procedures for producing compression‑moulded sheets and test specimens, and reference to machining and moulding practices to ensure comparable geometries.
• Conditioning of specimens: Environmental conditioning (standard atmospheres) and storage practices prior to testing to minimise variability.
• Property determination: Test methods for mechanical, thermal and physical properties relevant to PE‑UHMW, with procedures aimed at reproducibility rather than absolute equivalence to different specimen types.
• Normative test methods included: Annexes provide normative methods such as melt volume‑flow rate (MVR) determination, elongational stress testing (F(150/10)), and Charpy double‑notched impact strength for PE‑UHMW.
• Target materials: Focus on ultra‑high‑molecular‑weight polyethylene grades with very low flow (MFR threshold above).

Practical Applications

Who uses EN ISO 21304-2:2021:

• Materials suppliers - to generate comparable property data for product datasheets and specifications.
• Testing laboratories - to standardise specimen preparation, conditioning and test execution for PE‑UHMW.
• OEMs and designers - to evaluate PE‑UHMW performance (toughness, elongational stress, thermal behaviour) for industrial applications such as wear parts, liners, medical devices and high‑performance components.
• Certification bodies and procurement teams - to verify compliance with material specifications and compare competing grades.

Practical benefits:

• Improved comparability of mechanical and thermal property data.
• Clear guidance on specimen production and conditioning to reduce test variability.
• Inclusion of specific PE‑UHMW methods (MVR, elongational stress, Charpy impact) tailored to ultra‑high‑molecular‑weight polyethylene.

Related Standards

• ISO 21304-1 - Designation system and basis for specifications for PE‑UHMW
• ISO 10350-1 - Acquisition and presentation of comparable single‑point data
• ISO 1133-1 / ISO 17855-1 - MFR/MVR determination references
• Additional references: ISO 527, ISO 178, ISO 15527, ISO 291 and other normative test standards cited within EN ISO 21304-2:2021.

Keywords: EN ISO 21304-2:2021, PE‑UHMW, ultra-high-molecular-weight polyethylene, test specimens, moulding and extrusion materials, MFR, conditioning, compression moulding, material properties.

Standards Content (Sample)

SLOVENSKI STANDARD
01-marec-2021
Nadomešča:
SIST EN ISO 11542-2:2000
SIST EN ISO 11542-2:2000/AC:2009
Polimerni materiali - Materiali na osnovi polietilena z ultra visoko molsko maso
(PE-UHMW) za oblikovanje in ekstrudiranje - 2. del: Priprava preskušancev in
ugotavljanje lastnosti (ISO 21304-2:2021)
Plastics - Ultra-high-molecular-weight polyethylene (PE-UHMW) moulding and extrusion
materials - Part 2: Preparation of test specimens and determination of properties (ISO
21304-2:2021)
Kunststoffe - Ultrahochmolekulare Polyethylen (PE-UHMW)-Werkstoffe - Teil 2:
Herstellung von Probekörpern und Bestimmung von Eigenschaften (ISO 21304-2:2021)
Plastiques - Matériaux à base de polyéthylène à très haute masse moléculaire (PE-
UHMW) pour moulage et extrusion - Partie 2: Préparation des éprouvettes et
détermination des propriétés (ISO 21304-2:2021)
Ta slovenski standard je istoveten z: EN ISO 21304-2:2021
ICS:
83.080.20 Plastomeri Thermoplastic materials
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN ISO 21304-2
EUROPEAN STANDARD
NORME EUROPÉENNE
January 2021
EUROPÄISCHE NORM
ICS 83.080.20 Supersedes EN ISO 11542-2:1998
English Version
Plastics - Ultra-high-molecular-weight polyethylene (PE-
UHMW) moulding and extrusion materials - Part 2:
Preparation of test specimens and determination of
properties (ISO 21304-2:2021)
Plastiques - Matériaux à base de polyéthylène à très Kunststoffe - Ultrahochmolekulare Polyethylen (PE-
haute masse moléculaire (PE-UHMW) pour moulage et UHMW)-Werkstoffe - Teil 2: Herstellung von
extrusion - Partie 2: Préparation des éprouvettes et Probekörpern und Bestimmung von Eigenschaften
détermination des propriétés (ISO 21304-2:2021) (ISO 21304-2:2021)
This European Standard was approved by CEN on 9 January 2021.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this
European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references
concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN
member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by
translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and
United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2021 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 21304-2:2021 E
worldwide for CEN national Members.

Contents Page
European foreword . 3

European foreword
This document (EN ISO 21304-2:2021) has been prepared by Technical Committee ISO/TC 61 "Plastics"
in collaboration with Technical Committee CEN/TC 249 “Plastics” the secretariat of which is held by
NBN.
This European Standard shall be given the status of a national standard, either by publication of an
identical text or by endorsement, at the latest by July 2021, and conflicting national standards shall be
withdrawn at the latest by July 2021.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN ISO 11542-2:1998.
According to the CEN-CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,
Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of
North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the
United Kingdom.
Endorsement notice
The text of ISO 21304-2:2021 has been approved by CEN as EN ISO 21304-2:2021 without any
modification.
INTERNATIONAL ISO
STANDARD 21304-2
First edition
2021-01
Plastics — Ultra-high-molecular-
weight polyethylene (PE-UHMW)
moulding and extrusion materials —
Part 2:
Preparation of test specimens and
determination of properties
Plastiques — Matériaux à base de polyéthylène à très haute masse
moléculaire (PE-UHMW) pour moulage et extrusion —
Partie 2: Préparation des éprouvettes et détermination des propriétés
Reference number
ISO 21304-2:2021(E)
©
ISO 2021
ISO 21304-2:2021(E)
© ISO 2021
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting
on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address
below or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
ii © ISO 2021 – All rights reserved

ISO 21304-2:2021(E)
Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 3
4 Preparation of test specimens . 3
4.1 Treatment of the material before moulding . 3
4.2 Compression moulding . 3
5 Conditioning of test specimens . 4
6 Determination of properties . 4
Annex A (normative) Method for determining the melt volume-flow rate of PE-UHMW materials .8
Annex B (normative) Method for determining the elongational stress of PE-UHMW
moulding materials .11
Annex C (normative) Method for determining the Charpy double-notched impact strength
of PE-UHMW moulding material .17
Bibliography .20
ISO 21304-2:2021(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/ directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www .iso .org/ patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www .iso .org/
iso/ foreword .html.
This document was prepared by Technical Committee ISO/TC 61, Plastics, Subcommittee SC 9,
Thermoplastic materials, in collaboration with the European Committee for Standardization (CEN)
Technical Committee CEN/TC 249, Plastics, in accordance with the Agreement on technical cooperation
between ISO and CEN (Vienna Agreement).
This first edition of ISO 21304-2 cancels and replaces ISO 11542-2:1998, which has been technically
revised. It also incorporates the Technical Corrigendum ISO 11542-2:1998/Cor 1:2007.
The main changes compared to the previous edition are as follows:
— updated the normative references to the latest version;
— added terms and definitions (see Clause 3);
— revised the contents and structures of Table 2 and Table 3 according to the revised ISO 10350-1;
— added new Annex A;
— revised the masses of weights used to load specimen in Table B.1 (former Table A.1);
— revised Figure B.1, Figure B.2, Figure B.3 and Figure C.1 (former Figures A.1, A.2, A.3 and B.1).
A list of all parts in the ISO 21304 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www .iso .org/ members .html.
iv © ISO 2021 – All rights reserved

INTERNATIONAL STANDARD ISO 21304-2:2021(E)
Plastics — Ultra-high-molecular-weight polyethylene (PE-
UHMW) moulding and extrusion materials —
Part 2:
Preparation of test specimens and determination of
properties
1 Scope
This document specifies the methods of preparation of test specimens and the test methods to be
used in determining the properties of PE-UHMW moulding and extrusion materials. It gives the
requirements for handling test material and for conditioning both the test material before moulding
and the specimens before testing.
This document gives the procedures and conditions for the preparation of test specimens and
procedures for measuring properties of the materials from which these specimens are made. Properties
and test methods which are suitable and necessary to characterize PE-UHMW moulding and extrusion
materials are listed.
The properties have been selected from the general test methods in ISO 10350-1. Other test methods in
wide use for or of particular significance to these moulding and extrusion materials are also included in
this document, as are the designatory properties specified in ISO 21304-1. This document specifies the
materials with MFR less than 0,1 g/10 min at 190 °C /21,6 kg based on ISO 17855-1.
The methods of preparation and conditioning, the specimen dimensions and the test procedures
specified in this document are used in order to obtain reproducible and comparable test results. Values
determined will not necessarily be identical to those obtained using specimens of different dimensions
or prepared using different procedures.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 62, Plastics — Determination of water absorption
ISO 75-1, Plastics — Determination of temperature of deflection under load — Part 1: General test method
ISO 75-2, Plastics — Determination of temperature of deflection under load — Part 2: Plastics and ebonite
ISO 178, Plastics — Determination of flexural properties
ISO 179-1, Plastics — Determination of Charpy impact properties — Part 1: Non-instrumented impact test
ISO 291, Plastics — Standard atmospheres for conditioning and testing
ISO 293, Plastics — Compression moulding of test specimens of thermoplastic materials
ISO 527-1, Plastics — Determination of tensile properties — Part 1: General principles
ISO 527-2, Plastics — Determination of tensile properties — Part 2: Test conditions for moulding and
extrusion plastics
ISO 21304-2:2021(E)
ISO 527-4, Plastics — Determination of tensile properties — Part 4: Test conditions for isotropic and
orthotropic fibre-reinforced plastics composites
ISO 899-1, Plastics — Determination of creep behaviour — Part 1: Tensile creep
ISO 1133-1, Plastics — Determination of the melt mass-flow rate (MFR) and melt volume-flow rate (MVR)
of thermoplastics — Part 1: Standard method
ISO 1183-1, Plastics — Methods for determining the density of non-cellular plastics — Part 1: Immersion
method, liquid pycnometer method and titration method
ISO 1183-2, Plastics — Methods for determining the density of non-cellular plastics — Part 2: Density
gradient column method
ISO 1628-3, Plastics — Determination of the viscosity of polymers in dilute solution using capillary
viscometers — Part 3: Polyethylenes and polypropylenes
ISO 2818, Plastics — Preparation of test specimens by machining
ISO 4589-2, Plastics — Determination of burning behaviour by oxygen index — Part 2: Ambient-
temperature test
ISO 8256, Plastics — Determination of tensile-impact strength
ISO 10350-1, Plastics — Acquisition and presentation of comparable single-point data — Part 1: Moulding
materials
ISO 11357-2, Plastics — Differential scanning calorimetry (DSC) — Part 2: Determination of glass transition
temperature and step height
ISO 11357-3, Plastics — Differential scanning calorimetry (DSC) — Part 3: Determination of temperature
and enthalpy of melting and crystallization
ISO 11359-2, Plastics — Thermomechanical analysis (TMA) — Part 2: Determination of coefficient of linear
thermal expansion and glass transition temperature
ISO 15527, Plastics — Compression-moulded sheets of polyethylene (PE-UHMW, PE-HD) — Requirements
and test methods
ISO 20753, Plastics — Test specimens
ISO 21304-1, Plastics — Ultra-high-molecular-weight polyethylene (PE-UHMW) moulding and extrusion
materials — Part 1: Designation system and basis for specifications
IEC 60112, Method for the determination of the proof and the comparative tracking indices of solid
insulating materials
IEC 60243-1, Electrical strength of insulating materials — Test methods — Part 1: Tests at power
frequencies
IEC 60296, Fluids for electrotechnical applications — Unused mineral insulating oils for transformers and
switchgear
ISO/IEC 60695-11-10, Fire hazard testing — Part 11-10: Test flames — 50 W horizontal and vertical flame
test methods
IEC 62631-2-1, Dielectric and resistive properties of solid insulating materials-Part 2-1:Relative permittivity
and dissipation factor-Technical frequencies (0,1 Hz to 10 MHz)-AC Methods
IEC 62631-3-1, Dielectric and resistive properties of solid insulating materials — Part 3-1: Determination
of resistive properties (DC methods) — Volume resistance and volume resistivity — General method
2 © ISO 2021 – All rights reserved

ISO 21304-2:2021(E)
IEC 62631-3-2, Dielectric and resistive properties of solid insulating materials — Part 3-2: Determination
of resistive properties (DC methods) — Surface resistance and surface resistivity
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org/
3.1
elongational stress
F
(150/10)
tensile stress (force divided by initial cross-sectional area) required to increase the measured length of
a test specimen by 600 % at 150 °C over a 10 min period
Note 1 to entry: It is expressed in megapascals (MPa).
3.2
Charpy double-notched impact strength
impact energy absorbed in breaking a double-notched specimen, referred to the original cross-sectional
area of the specimen, at double notches (see Figure C.1)
Note 1 to entry: It is expressed in kilojoules per square metre (kJ/m ).
4 Preparation of test specimens
4.1 Treatment of the material before moulding
Before processing, no pretreatment of the material sample is normally necessary.
4.2 Compression moulding
Compression-moulded sheets shall be prepared in accordance with ISO 293 using the conditions
specified in Table 1. The test specimens for the determination of the properties shall be machined from
the compression-moulded sheets in accordance with ISO 2818 or stamped.
Table 1 — Compression-moulding conditions
Material Moulding Preheating Preheating Full Full- Average Demoulding
temperature pressure time pressure pressure cooling temperature
time rate
°C MPa min MPa °C
min °C/min
All grades 210 5 5 to 15 10 30 ± 1 15 ≤ 40
A flash mould (see ISO 293) may be used, but it is necessary to start cooling while simultaneously applying
the full pressure. This avoids the melt being pressed out of the frame and also avoids sink marks.
For thicker sheet (≥4 mm), a positive mould (see ISO 293) shall be used. The preheating time depends
on the type of mould and the type of energy input (steam, electricity).
For frame moulds, 5 min is usually sufficient but for positive moulds, due to the bigger mass, a
preheating time of 5 min to 15 min can be necessary, especially if electric heating is used.
ISO 21304-2:2021(E)
5 Conditioning of test specimens
Unfilled PE-UHMW test specimens shall be conditioned in accordance with ISO 291 for at least 40 h
at 23 °C ± 2 °C, with no relative humidity requirement. Test specimens containing fillers and / or
additives that are susceptible to moisture uptake shall be conditioned for at least 40 h at 23 °C ± 2 °C
and 50 % ± 10 % relative humidity.
6 Determination of properties
In the determination of properties and the presentation of data, the standards, supplementary
instructions and notes given in ISO 10350-1 shall be applied. Unless specifically stated in Table 2 and
Table 3, testing of unfilled PE-UHMW test specimens shall be carried out at a standard temperature of
23 °C ± 2 °C with no relative humidity requirement. Specimens made from materials containing fillers
and / or additives that are susceptible to moisture uptake shall be tested in a standard atmosphere of
23 °C ± 2 °C and 50 % ± 10 % relative humidity.
Table 2 is compiled from ISO 10350-1, and the properties listed are those which are appropriate
to PE-UHMW moulding and extrusion materials. These properties are those considered useful for
comparisons of data generated for different thermoplastics.
Table 3 contains those properties, not found specifically in Table 2, which are in wide use or of particular
significance in the practical characterization of PE-UHMW moulding and extrusion materials.
Table 2 — General properties and test conditions (selected from ISO 10350-1)
Specimen type Specimen
Test conditions and sup-
Property Symbol Standard Unit
(dimensions in Prepara-
plementary instructions
a
mm) tion
1 Mechanical properties
1.1 Tensile modulus E Test speed 1 mm/min
t
MPa
1.2 Yield stress σ Failure with yielding
y
1.3 Yield strain ε
Test speed 50 mm/min
y
%
Nominal strain at
1.4 ε
ISO 527-1
...