SIST EN ISO 12086-2:2006

SLOVENSKI STANDARD
SIST EN ISO 12086-2:2006
01-april-2006
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Plastics - Fluoropolymer dispersions and moulding and extrusion materials - Part 2:
Preparation of test specimens and determination of properties (ISO 12086-2:2006)
Kunststoffe - Fluorpolymerdispersionen, Formmassen und Extrusionsmaterialien - Teil 2:
Herstellung von Probekörpern und Bestimmung von Eigenschaften (ISO 12086-2:2006)
Plastiques - Polymeres fluorés: dispersions et matériaux pour moulage et extrusion -
Partie 2: Préparation des éprouvettes et détermination des propriétés (ISO 12086-
2:2006)
Ta slovenski standard je istoveten z: EN ISO 12086-2:2006
ICS:
83.080.20 Plastomeri Thermoplastic materials
SIST EN ISO 12086-2:2006 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN ISO 12086-2:2006

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SIST EN ISO 12086-2:2006
EUROPEAN STANDARD
EN ISO 12086-2
NORME EUROPÉENNE
EUROPÄISCHE NORM
February 2006
ICS 83.080.20 Supersedes EN ISO 12086-2:1999
English Version
Plastics - Fluoropolymer dispersions and moulding and extrusion
materials - Part 2: Preparation of test specimens and
determination of properties (ISO 12086-2:2006)
Plastiques - Polymères fluorés: dispersions et matériaux Kunststoffe - Fluorpolymerdispersionen, Formmassen und
pour moulage et extrusion - Partie 2: Préparation des Extrusionsmaterialien - Teil 2: Herstellung von
éprouvettes et détermination des propriétés (ISO 12086- Probekörpern und Bestimmung von Eigenschaften (ISO
2:2006) 12086-2:2006)
This European Standard was approved by CEN on 13 February 2006.
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 Central Secretariat 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 Central Secretariat has the same status as the official
versions.
CEN members are the national standards bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,
Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania,
Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36  B-1050 Brussels
© 2006 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 12086-2:2006: E
worldwide for CEN national Members.

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SIST EN ISO 12086-2:2006

EN ISO 12086-2:2006 (E)





Foreword


This document (EN ISO 12086-2:2006) 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 IBN.

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 August 2006, and conflicting national
standards shall be withdrawn at the latest by August 2006.

This document supersedes EN ISO 12086-2:1999.

According to the CEN/CENELEC Internal Regulations, the national standards organizations of
the following countries are bound to implement this European Standard: Austria, Belgium,
Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary,
Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland,
Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.


Endorsement notice

The text of ISO 12086-2:2006 has been approved by CEN as EN ISO 12086-2:2006 without any
modifications.

2

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SIST EN ISO 12086-2:2006


INTERNATIONAL ISO
STANDARD 12086-2
Second edition
2006-02-15


Plastics — Fluoropolymer dispersions
and moulding and extrusion materials —
Part 2:
Preparation of test specimens
and determination of properties
Plastiques — Polymères fluorés: dispersions et matériaux pour
moulage et extrusion —
Partie 2: Préparation des éprouvettes et détermination des propriétés





Reference number
ISO 12086-2:2006(E)
©
ISO 2006

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SIST EN ISO 12086-2:2006
ISO 12086-2:2006(E)
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ii © ISO 2006 – All rights reserved

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SIST EN ISO 12086-2:2006
ISO 12086-2:2006(E)
Contents Page
Foreword. iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions. 3
4 Abbreviated terms and symbols . 4
5 Sampling. 5
6 Preparation of test specimens . 5
7 Conditioning and test conditions. 5
8 General testing of fluoropolymers. 5
8.1 Electrical properties . 6
8.2 Mechanical properties. 8
8.3 Thermal-transition temperatures . 10
8.4 Density . 11
8.5 Flammability by oxygen index. 11
8.6 Particle size and size distribution. 11
9 Testing of fluoropolymer dispersions . 17
9.1 General. 17
9.2 Preparation of test samples. 18
9.3 Isolation of PTFE from dispersion . 18
9.4 Coagulum in dispersions. 19
9.5 Percentage polymer and surfactant in aqueous dispersion . 19
9.6 PTFE solids content by hydrometer . 20
9.7 pH of dispersions. 21
10 Testing of PTFE and closely related materials . 21
10.1 General. 21
10.2 Preparation of test specimens by moulding. 21
10.3 Bulk density. 23
10.4 Extrusion pressure . 27
10.5 Powder-flow time . 32
10.6 Standard specific gravity (SSG), extended specific gravity (ESG) and thermal-instability
index (TII) . 34
10.7 Stretching-void index (SVI). 37
11 Testing of conventionally melt-processible fluoropolymers . 38
11.1 Preparation of test specimens by moulding. 38
11.2 Melt mass-flow rate (MFR) and melt volume-flow rate (MVR) . 39
12 Other test methods used with fluoropolymers. 41
12.1 Brittleness temperature of plastics and elastomers by impact . 41
12.2 Coefficients of static and kinetic friction . 41
12.3 Zero-strength time . 41
Annex A (informative) Listing of test methods (alphabetical order). 42
Annex B (informative) Designatory properties for common fluoropolymer types with
cross-reference listing to the tables for codes in ISO 12086-1 and the test methods in
ISO 12086-2. 43
Bibliography . 45
© ISO 2006 – All rights reserved iii

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SIST EN ISO 12086-2:2006
ISO 12086-2:2006(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.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
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.
ISO 12086-2 was prepared by Technical Committee ISO/TC 61, Plastics, Subcommittee SC 9, Thermoplastic
materials.
This second edition cancels and replaces the first edition (ISO 12086-2:1995), which has been technically
revised.
ISO 12086 consists of the following parts, under the general title Plastics — Fluoropolymer dispersions and
moulding and extrusion materials:
⎯ Part 1: Designation system and basis for specifications
⎯ Part 2: Preparation of test specimens and determination of properties

iv © ISO 2006 – All rights reserved

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SIST EN ISO 12086-2:2006
INTERNATIONAL STANDARD ISO 12086-2:2006(E)

Plastics — Fluoropolymer dispersions and moulding and
extrusion materials —
Part 2:
Preparation of test specimens and determination of properties
SAFETY STATEMENT — Persons using this document should be familiar with normal laboratory
practice, if applicable. This document does not purport to address all of the safety concerns, if any,
associated with its use. It is the responsibility of the user to establish appropriate safety and health
practices and to ensure compliance with any regulatory requirements. The warnings in
Subclauses 8.6.2.1, 9.7 and 10.6.1.4 point out specific hazards.
1 Scope
1.1 This part of ISO 12086 describes the preparation of test specimens and provides test methods to define
characteristics of thermoplastic fluoropolymer resins. Results from the testing may be used as the basis for
designation, material specifications or both. This part of ISO 12086 describes the conditions of test for
determining both designatory and other properties of the homopolymers and various copolymers of
fluoromonomers, as dispersions or powders for moulding, extrusion and other uses. The test procedures
included are appropriate for, but are not restricted to, the fluoropolymers listed in Clause 4 and for which
designatory properties are specified in ISO 12086-1.
1.2 The properties of semi-finished and finished products made from fluoropolymer resins depend on the
material used, the shape of the product, the physical and morphological state of the material resulting from the
processing operations, and on the test conditions. Therefore, to obtain reproducible test results, the defined
methods of preparation of test specimens and defined test conditions given in this part of ISO 12086 must be
applied.
1.3 Agreements between vendor and purchaser should preferably be based on properties measured using
the specimens and test conditions described in this part of ISO 12086.
2 Normative references
The following referenced documents are indispensable for the application 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 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 180, Plastics — Determination of lzod impact strength
ISO 291, Plastics — Standard atmospheres for conditioning and testing
ISO 293, Plastics — Compression moulding of test specimens of thermoplastic materials
ISO 472, Plastics — Vocabulary
ISO 527-1, Plastics — Determination of tensile properties — Part 1: General principles
© ISO 2006 – All rights reserved 1

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SIST EN ISO 12086-2:2006
ISO 12086-2:2006(E)
ISO 527-2, Plastics — Determination of tensile properties — Part 2: Test conditions for moulding and
extrusion plastics
ISO 527-3, Plastics — Determination of tensile properties — Part 3: Test conditions for films and sheets
ISO 565, Test sieves — Metal wire cloth, perforated metal plate and electroformed sheet — Nominal sizes of
openings
ISO 976, Rubber and plastics — Polymer dispersions and rubber latices — Determination of pH
ISO 1043-1, Plastics — Symbols and abbreviated terms — Part 1: Basic polymers and their special
characteristics
ISO 1043-2, Plastics — Symbols and abbreviated terms — Part 2: Fillers and reinforcing materials
ISO 1133:2005, Plastics — Determination of the melt mass-flow rate (MFR) and the melt volume-flow rate
(MVR) of thermoplastics
ISO 1183-1, Plastics — Methods for determining the density of non-cellular plastics — Part 1: Immersion
method, liquid pyknometer method and titration method
ISO 1183-2, Plastics — Methods for determining the density of non-cellular plastics — Part 2: Density gradient
column method
ISO 4589 (all parts), Plastics — Determination of burning behaviour by oxygen index
ISO 11357-2, Plastics — Differential scanning calorimetry (DSC) — Part 2: Determination of glass transition
temperature
ISO 11357-3, Plastics — Differential scanning calorimetry (DSC) — Determination of temperature and
enthalpy of melting and crystallization
ISO 12086-1, Plastics — Fluoropolymer dispersions and moulding and extrusion materials — Part 1:
Designation system and basis for specifications
ISO 13320-1, Particle size analysis — Laser diffraction methods — General principles
IEC 60093, Methods of test for volume resistivity and surface resistivity of solid electrical insulating materials
IEC 60243-1, Electrical strength of insulating materials — Test methods — Part 1: Tests at power frequencies
IEC 60250, Recommended methods for the determination of the permittivity and dielectric dissipation factor of
electrical insulating materials at power, audio and radio frequencies including metre wavelengths
ASTM D 746, Standard Test Method for Brittleness Temperature of Plastics and Elastomers by Impact
ASTM D 1430, Standard Classification System for Polychlorotrifluoroethylene (PCTFE) Plastics
ASTM D 1894, Standard Test Method for Static and Kinetic Coefficients of Friction of Plastic Film and
Sheeting
ASTM D 3418, Standard Test Method for Transition Temperatures of Polymers by Differential Scanning
Calorimetry
ASTM D 4052, Standard Test method for Density and Relative Density of Liquids by Digital Density Meter
ASTM D 4591, Standard Test Method for Determining Temperatures and Heats of Transitions of
Fluoropolymers by Differential Scanning Calorimetry
ASTM D 4894, Standard Specification for Polytetrafluoroethylene (PTFE) Granular Molding and Ram
Extrusion Materials
ASTM D 4895, Standard Specification for Polytetrafluoroethylene (PTFE) Resin Produced from Dispersion
BS 4641:1986, Method for specifying electroplated coatings of chromium for engineering purposes
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SIST EN ISO 12086-2:2006
ISO 12086-2:2006(E)
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 472 and the following terms and
definitions apply. The terms listed in 3.1 to 3.3 are repeated from ISO 472 to be sure there is no
misunderstanding.
3.1
dispersion
heterogeneous system in which a finely divided material is distributed in another material
3.2
fluoroplastic
plastic based on polymers made with monomers containing one or more atoms of fluorine, or copolymers of
such monomers with other monomers, the fluoromonomer being in the greatest amount by mass
3.3
latex
colloidal aqueous dispersion of a polymeric material
3.4
amorphous
noncrystalline, or devoid of regular structure
3.5
bulk density
mass (in grams) per litre of material, measured under the conditions of the test
3.6
copolymer
polymer formed from two or more types of monomer
3.7
emulsion polymer
〈fluoropolymer materials〉 material isolated from its polymerization medium as a colloidal aqueous dispersion
of the polymer solids
NOTE This definition, used in the fluoropolymer industry, is similar to that for “latex” in ISO 472 and is quite different
from the definition for “emulsion” in ISO 472.
3.8
fluorocarbon plastic
plastic based on polymers made from perfluoromonomers only
3.9
fluoropolymer
synonymous with fluoroplastic (see 3.2)
3.10
melt-processible
capable of being processed by, for example, injection moulding, screw extrusion and other operations typically
used with thermoplastics
3.11
preforming
compacting powdered PTFE material under pressure in a mould to produce a solid object, called a preform,
that is capable of being handled
NOTE With PTFE, “moulding” and “compaction” are terms used interchangeably with “preforming”.
© ISO 2006 – All rights reserved 3

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SIST EN ISO 12086-2:2006
ISO 12086-2:2006(E)
3.12
sintering
〈PTFE〉 thermal treatment during which the material is melted and recrystallized by cooling, with coalescence
occurring during the treatment
3.13
standard specific gravity
SSG
specific gravity of a specimen of PTFE material preformed, sintered and cooled through the crystallization
point at a rate of 1 °C per minute in accordance with the appropriate sintering schedule as described in this
part of ISO 12086
NOTE The SSG of unmodified PTFE is inversely related to its molecular mass.
3.14
suspension polymer
polymer isolated from its liquid polymerization medium as a solid having a particle size well above colloidal
dimensions
3.15
zero-strength time
ZST
measure of the relative molecular mass of PCTFE
4 Abbreviated terms and symbols
4.1 The abbreviated terms given in ISO 1043-1 and ISO 1043-2 are applicable to this part of ISO 12086.
4.2 This part of ISO 12086 is particularly concerned with, but is not limited to, test methods for the materials
listed below:
ECTFE ethylene-chlorotrifluoroethylene copolymer
EFEP ethylene-tetrafluoroethylene-hexafluoropropene copolymer
ETFE ethylene-tetrafluoroethylene copolymer
FEP perfluoro(ethylene-propene) copolymer
PCTFE polychlorotrifluoroethylene
PFA perfluoro(alkoxy alkane)
PTFE polytetrafluoroethylene
PVDF poly(vinylidene fluoride)
PVF poly(vinyl fluoride)
TFE/PDD tetrafluoroethylene-perfluorodioxole copolymer
VDF/CTFE vinylidene fluoride-chlorotrifluoroethylene copolymer
VDF/HFP vinylidene fluoride-hexafluoropropene copolymer
VDF/TFE vinylidene fluoride-tetrafluoroethylene copolymer
VDF/TFE/HFP vinylidene fluoride-tetrafluoroethylene-hexafluoropropene copolymer
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SIST EN ISO 12086-2:2006
ISO 12086-2:2006(E)
4.3 For the purposes of this part of ISO 12086, the following additional abbreviated terms apply.
AF amorphous fluoropolymer
ESG extended specific gravity (see 10.6)
MFR melt mass-flow rate (see 11.2)
MVR melt volume-flow rate (see 11.2)
SSG standard specific gravity (see 10.6)
SVI stretching-void index (see 10.7)
TII thermal-instability index (see 10.6)
ZST zero-strength time (see 12.3)
5 Sampling
Sampling shall be statistically adequate to satisfy the requirements of this part of ISO 12086.
6 Preparation of test specimens
Where applicable, ISO standards shall be followed for the preparation of test specimens. In some instances,
special procedures are required that are described either in the general discussion or in the method.
7 Conditioning and test conditions
7.1 For determinations of specific gravity, tensile properties and electrical properties, condition the moulded
test specimens in atmosphere 23 of ISO 291 for a period of at least 4 h prior to testing. The other
determinations require no conditioning.
NOTE For PVDF, some producers recommend waiting one week after moulding before testing in order to minimize
the effects of post-crystallization.
7.2 Conduct tests at a laboratory temperature of 23 °C ± 2 °C for determining specific gravity, tensile
properties and electrical properties only. (See the Note for comments related to PTFE.) Since the
fluoropolymer resins do not absorb water, the maintenance of constant humidity during testing is not
necessary. Conduct tests for melt flow rate and melting-peak temperature under ordinary laboratory conditions.
NOTE A minimum temperature of 22 °C should preferably be maintained with PTFE due to its first-order transition
just below 22 °C that affects properties determined at slightly lower temperatures. This effect of temperature is especially
important during the determination of density/specific gravity.
8 General testing of fluoropolymers
Properties required for designation or specification, or both, shall be determined in accordance with the
international or national standards listed in Clause 2 or the procedures given in this part of ISO 12086.
Tables of values of the designatory properties and corresponding codes are included in ISO 12086-1.
Tables of values and codes are also included in this part of ISO 12086 for many of the other properties that
are needed to supplement the designatory properties for specification and other purposes.
© ISO 2006 – All rights reserved 5

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SIST EN ISO 12086-2:2006
ISO 12086-2:2006(E)
8.1 Electrical properties
8.1.1 Dielectric constant and dissipation factor
Determine these properties on three specimens, each 100 mm in diameter, in accordance with IEC 60250.
Typical frequencies used for testing are 100 Hz, 1 kHz, 1 MHz and 100 MHz. For some applications, it is
important to know the values at subambient and elevated temperatures. Codes for test frequencies and
values of the properties are given in Tables 1 and 2.
NOTE Electrical properties, like many other properties, vary with temperature.
Table 1 — Codes for test frequencies
Code Test frequency
2 100 Hz
3 1 kHz
6 1 MHz
8 100 MHz

Table 2 — Codes and ranges for dielectric constant and dissipation factor
Code Dielectric constant Code Dissipation factor
A < 1,6 A < 0,000 1
B 1,6 to < 1,8 B 0,000 1 to < 0,000 2
C 1,8 to < 2,0 C 0,000 2 to < 0,000 4
D 2,0 to < 2,2 D 0,000 4 to < 0,000 6
E 2,2 to < 2,4 E 0,000 6 to < 0,000 8
F 2,4 to < 2,6 F 0,000 8 to < 0,001 0
G 2,6 to < 2,8 G 0,001 0 to < 0,001 2
H 2,8 to < 3,0 H 0,001 2 to < 0,001 4
I 3,0 to < 3,2 I 0,001 4 to < 0,001 6
J 3,2 to < 3,4 J 0,001 6 to < 0,001 8
K 3,4 to < 3,6 K 0,001 8 to < 0,002 0
L 3,6 to < 4,0 L 0,002 0 to < 0,002 2
M 4,0 to < 4,5 M 0,002 2 to < 0,002 4
N 4,5 to < 5,0 N 0,002 4 to < 0,002 6
O 5,0 to < 5,5 O 0,002 6 to < 0,002 8
P 5,5 to < 6.0 P 0,002 8 to < 0,003 0
R 6,0 to < 6,5 Q 0,003 0 to < 0,003 5
S 6,5 to < 7,0 R 0,003 5 to < 0,004 0
T 7,0 to < 8.0 S 0,004 0 to < 0,006 0
U 8,0 to < 9,0 T 0,006 0 to < 0,008 0
V 9,0 to < 10,0 U 0,008 0 to < 0,010
W 10,0 to < 11,0 W 0,010 to < 0,030
X 11,0 to < 12,0 X 0,030 to < 0,10
Y 12,0 to < 14,0 Y u 0,1
Z W 14,0
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SIST EN ISO 12086-2:2006
ISO 12086-2:2006(E)
8.1.2 Dielectric strength (electric strength)
Determine this property in accordance with the procedures of IEC 60243-1. Codes for values of the property
are given in Table 3.
NOTE Dielectric strength, which is expressed in kilovolts per millimetre, varies with the thickness of the test specimen.
Table 3 — Codes and ranges for dielectric strength
Code Dielectric strength (kV/mm)
A < 5
B 5 to < 10
C 10 to < 15
D 15 to < 20
E 20 to < 25
F 25 to < 30
G 30 to < 35
H 35 to < 40
I 40 to < 45
J 45 to < 50
K 50 to < 55
L 55 to < 60
M 60 to < 65
N 65 to < 70
O 70 to < 75
P 75 to < 80
Q 80 to < 85
R 85 to < 90
S 90 to < 95
T 95 to < 100
U W 100

8.1.3 Surface resistivity
Deter
...