SIST EN ISO 14896:2009

SLOVENSKI STANDARD
SIST EN ISO 14896:2009
01-maj-2009
1DGRPHãþD
SIST EN ISO 14896:2002
3ROLPHUQLPDWHULDOL6XURYLQH]DSROLXUHWDQH'RORþHYDQMHL]RFLDQDWD,62

Plastics - Polyurethane raw materials - Determination of isocyanate content (ISO
14896:2009)
Kunststoffe - Polyurethanrohstoffe - Bestimmung des Isocyanatanteils (ISO 14896:2008)
Plastiques - Matières premières des polyuréthannes - Détermination de la teneur en
isocyanate (ISO 14896:2009)
Ta slovenski standard je istoveten z: EN ISO 14896:2009
ICS:
83.080.10 Duromeri Thermosetting materials
SIST EN ISO 14896:2009 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN ISO 14896:2009

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SIST EN ISO 14896:2009
EUROPEAN STANDARD
EN ISO 14896
NORME EUROPÉENNE
EUROPÄISCHE NORM
February 2009
ICS 83.080.10 Supersedes EN ISO 14896:2001
English Version
Plastics - Polyurethane raw materials - Determination of
isocyanate content (ISO 14896:2009)
Plastiques - Matières premières des polyuréthannes - Kunststoffe - Polyurethanrohstoffe - Bestimmung des
Détermination de la teneur en isocyanate (ISO 14896:2009) Isocyanatanteils (ISO 14896:2008)
This European Standard was approved by CEN on 19 January 2009.
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 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 Management Centre has the same status as the
official versions.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, 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: Avenue Marnix 17, B-1000 Brussels
© 2009 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 14896:2009: E
worldwide for CEN national Members.

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SIST EN ISO 14896:2009
EN ISO 14896:2009 (E)
Contents Page
Foreword .3

2

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SIST EN ISO 14896:2009
EN ISO 14896:2009 (E)
Foreword
This document (EN ISO 14896:2009) 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 August 2009, and conflicting national standards shall be withdrawn at
the latest by August 2009.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN ISO 14896:2001.
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, 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 the United Kingdom.
Endorsement notice
The text of ISO 14896:2009 has been approved by CEN as a EN ISO 14896:2009 without any modification.

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SIST EN ISO 14896:2009

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SIST EN ISO 14896:2009

INTERNATIONAL ISO
STANDARD 14896
Third edition
2009-02-15

Plastics — Polyurethane raw materials —
Determination of isocyanate content
Plastiques — Matières premières des polyuréthannes — Détermination
de la teneur en isocyanate




Reference number
ISO 14896:2009(E)
©
ISO 2009

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SIST EN ISO 14896:2009
ISO 14896:2009(E)
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©  ISO 2009
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ii © ISO 2009 – All rights reserved

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SIST EN ISO 14896:2009
ISO 14896:2009(E)
Contents Page
Foreword. iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions. 2
4 Principle. 2
4.1 Method A. 2
4.2 Method B. 2
5 Application . 2
6 Interferences . 2
7 Sampling. 3
8 Test conditions . 3
9 Reagents. 3
10 Apparatus . 4
11 Method A — Toluene/dibutylamine with aqueous HCI . 4
11.1 Procedure . 4
11.2 Expression of results . 5
11.3 Precision and bias . 6
11.4 Test report . 6
12 Method B — Toluene/TCB/DBA with methanolic HCI . 7
12.1 Procedure . 7
12.2 Expression of results . 8

12.3 Precision and bias . 8
12.4 Test report . 9

© ISO 2009 – All rights reserved iii

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SIST EN ISO 14896:2009
ISO 14896:2009(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 14896 was prepared by Technical Committee ISO/TC 61, Plastics, Subcommittee SC 12, Thermosetting
materials.
This third edition cancels and replaces the second edition (ISO 14896:2006), of which it constitutes a minor
revision, the main purpose of which was to combine the standard with its amendment
(ISO 14896:2006/Amd.1:2007), thereby adding a new subclause (12.1.8).

iv © ISO 2009 – All rights reserved

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SIST EN ISO 14896:2009
INTERNATIONAL STANDARD ISO 14896:2009(E)

Plastics — Polyurethane raw materials — Determination of
isocyanate content
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.
1 Scope
This lnternational Standard specifies two methods for the measurement of the isocyanate content of aromatic
isocyanates used as polyurethane raw materials. Method A is primarily applicable to refined toluene
diisocyanate (TDI), methylene-bis-(4-phenylisocyanate) (MDI) and their prepolymers. Method B is applicable
to refined, crude or modified isocyanates derived from toluene diisocyanate, methylene-
bis-(4-phenylisocyanate) and polymethylene polyphenylisocyanate. It can also be used for isomer mixtures of
toluene diisocyanate, methylene-bis-(4-phenylisocyanate) and polymethylene polyphenylisocyanate. Other
aromatic isocyanates may be analysed by this method if precautions are taken to verify suitability. It is not
applicable to blocked isocyanates.
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 385, Laboratory glassware — Burettes
ISO 648, Laboratory glassware — Single-volume pipettes
ISO 3696, Water for analytical laboratory use — Specification and test methods
ISO 4787, Laboratory glassware — Volumetric glassware — Methods for use and testing of capacity
ISO 4788, Laboratory glassware — Graduated measuring cylinders
ISO 6353-1, Reagents for chemical analysis — Part 1: General test methods
ISO 6353-2, Reagents for chemical analysis — Part 2: Specifications — First series
ISO 6353-3, Reagents for chemical analysis — Part 3: Specifications — Second series
ISO 14898:1999, Plastics — Aromatic isocyanates for use in the production of polyurethane — Determination
of acidity
© ISO 2009 – All rights reserved 1

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SIST EN ISO 14896:2009
ISO 14896:2009(E)
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
polyurethane
polymer prepared by the reaction of an organic di- or polyisocyanate with compounds containing two or more
hydroxyl groups
NOTE Polyurethanes may be thermosetting, thermoplastic, rigid or soft and flexible, cellular or non-cellular.
3.2
assay
percent by mass of a specific isocyanate present in a sample
3.3
isocyanate content
NCO content
percent by mass of the NCO groups present in a sample
3.4
amine equivalent
mass of sample that will combine with 1 gram-equivalent of dibutylamine
4 Principle
4.1 Method A
The isocyanate sample is reacted with an excess of dibutylamine in toluene to form the corresponding
substituted urea. After cooling to room temperature, acetone is added as a co-solvent, then the reaction
mixture is back-titrated with standardized aqueous HCI using potentiometric or colorimetric end point
determination.
4.2 Method B
The isocyanate sample is reacted with an excess of dibutylamine in a toluene/trichlorobenzene solvent to form
the corresponding substituted urea. After cooling to room temperature, the reaction mixture is diluted with
methanol and back-titrated potentiometrically or colorimetrically with methanolic hydrochloric acid. See also
12.1.8.
5 Application
These test methods can be used for research or for quality control purposes to characterize isocyanates used
in polyurethane products.
6 Interferences
Phosgene, the carbamyl chloride of the isocyanate, hydrogen chloride and any other acidic or basic
compounds will interfere. In refined isocyanates, these impurities are usually present in such small amounts
that they do not affect the determination; however, some crude or modified isocyanates may contain acidities
of up to approximately 0,3 %, so the value reported for the NCO content of unrefined isocyanates should
preferably be designated as “corrected” or “uncorrected” for acidity.
2 © ISO 2009 – All rights reserved

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SIST EN ISO 14896:2009
ISO 14896:2009(E)
7 Sampling
Since organic isocyanates react with atmospheric moisture, take special precautions in sampling (see
warning). Usual sampling methods (for example, sampling an open drum with a thief), even when conducted
rapidly, can cause contamination of the sample with insoluble ureas; therefore, blanket the sample with a dry
inert gas (e.g. nitrogen, argon or dried air) at all times.
WARNING — Organic isocyanates are hazardous when absorbed through the skin, or when the
vapours are breathed. Provide adequate ventilation and wear protective gloves and eyeglasses.
8 Test conditions
Since isocyanates react with moisture, keep the laboratory humidity low, preferably below 50 % relative
humidity.
9 Reagents
Us
...