SIST-TP CEN ISO/TR 11827:2016

SLOVENSKI STANDARD
kSIST-TP FprCEN ISO/TR 11827:2016
01-marec-2016
Tekstilije - Preskušanje sestave - Identifikacija vlaken (ISO/TR 11827:2012)
Textiles - Composition testing - Identification of fibres (ISO/TR 11827:2012)
Textiles - Essai de composition - Identification des fibres (ISO/TR 11827:2012)
Ta slovenski standard je istoveten z: FprCEN ISO/TR 11827
ICS:
59.060.01 Tekstilna vlakna na splošno Textile fibres in general
kSIST-TP FprCEN ISO/TR 11827:2016 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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kSIST-TP FprCEN ISO/TR 11827:2016

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kSIST-TP FprCEN ISO/TR 11827:2016

TECHNICAL ISO/TR
REPORT 11827
First edition
2012-06-01

Textiles — Composition testing —
Identification of fibres
Textiles — Essai de composition — Identification des fibres




Reference number
ISO/TR 11827:2012(E)
©
ISO 2012

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kSIST-TP FprCEN ISO/TR 11827:2016
ISO/TR 11827:2012(E)

COPYRIGHT PROTECTED DOCUMENT


©  ISO 2012
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means,
electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or
ISO's member body in the country of the requester.
ISO copyright office
Case postale 56 • CH-1211 Geneva 20
Tel. + 41 22 749 01 11
Fax + 41 22 749 09 47
E-mail copyright@iso.org
Web www.iso.org
Published in Switzerland

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ISO/TR 11827:2012(E)
Contents Page
Foreword .iv
Introduction.v
1 Scope.1
2 Safety note .1
3 Normative references.2
4 Terms and definitions .2
5 Principle.2
6 Apparatus and preparation of solutions.3
6.1 Apparatus.3
6.2 Preparation of solutions .3
7 Techniques.4
7.1 Microscopy.4
7.2 Flame tests.6
7.3 Staining Tests .7
7.4 Solubility Tests .7
7.5 Infrared Spectroscopy .8
7.6 Thermal Analysis.12
7.7 Density measurement methods .14
7.8 Other Instrumental Methods.14
8 Examples of procedures.15
8.1 Procedure using microscopy, solubility tests and FT-IR tests (examples) .15
8.2 Procedure using solubility tests (examples).17
8.3 Procedure using combustion tests and melting point determination (example) .19
8.4 Procedure using microscopy, FT-IR analysis and thermal analysis, case of bicomponent
fibres (examples) .19
Annex A (informative) Characteristics relative to fibre identification testing .24
Annex B (informative) Photomicrographs of Fibres (Light Microscopy) .29
Annex C (informative) Scanning Electron Micrographs of Fibres .34
Annex D (informative) Solubility of fibres .42
Annex E (informative) Examples of Infrared Spectra .45
Annex F (informative) Thermal transition temperature.50
Annex G (informative) Density.54
Annex H (informative) Alphabetical index of figures .55
Bibliography.58

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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.
In exceptional circumstances, when a technical committee has collected data of a different kind from that
which is normally published as an International Standard (“state of the art”, for example), it may decide by a
simple majority vote of its participating members to publish a Technical Report. A Technical Report is entirely
informative in nature and does not have to be reviewed until the data it provides are considered to be no
longer valid or useful.
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/TR 11827 was prepared by Technical Committee ISO/TC 38, Textiles.
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Introduction
The correct identification of fibres in textiles and the accurate determination of the composition of each fibre
present is a legal requirement in many countries throughout the world for imported textile goods and at the
point of sale to the public. Fibre identification can be carried out by a number of different techniques, e.g.
microscopy, solubility, spectroscopy, melting point, pyrolysis, density, refractive index, etc.
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kSIST-TP FprCEN ISO/TR 11827:2016
TECHNICAL REPORT ISO/TR 11827:2012(E)

Textiles — Composition testing — Identification of fibres
IMPORTANT — The electronic file of this document contains colours which are considered to be
useful for the correct understanding of the document. Users should therefore consider printing this
document using a colour printer.
1 Scope
This Technical Report describes procedures for the identification of natural and man-made fibres, and may be
used, when necessary, to coordinate with methods for the quantitative analysis of fibre blends.
Textile Fibres
Natural fibres Man-made fibres
Animal fibres Mineral fibres
Vegetable fibres
From organic From inorganic
chemistry
chemistry
Animal Hairs Asbestos
From Seed
Glass
Artificial fibres Synthetic fibres
Wool (Sheep)
Cotton
Metallic fibres
Cashmere, Mohair
Kapok
Cer amics
(Goat)
From cellulose
Other fibres
Car bon
Acrylic, Modacrylic
Alpaca, Guanaco,
Other fibres
Vicuna (Llama) Chlorofibre
Viscose, Cupro
From Stem
Angora (Rabbit) Fluorofibre
Modal, Lyocell
Other fibres Polyamide
Acetate, Triacetate
Polyester
Flax
Other fibres
Aramid
Secretion fibres Hemp
Polyimide
Ramie
Polyethylene
Jute
Silk
Polypropylene
Other fibres
Others
Other fibres
Polylactide
Elastane
Elastodiene
From leaf
(from latex)
Elastodiene
Protein fibres
Elastolefin
Sisal
Alginate
Melamine
Alfa
Other fibres
Polycarbamide
Other fibres
Trivinyl
From Fruit Elastomultiester
Polypropylene/
Polyamide-
Coir
bicomponent
Other fibres
Other fibres

Figure 1 — Classification of the textile fibres in relation to their origin
2 Safety note
This Technical Report calls for the use of substances/procedures that may be injurious to the health/
environment if appropriate conditions are not observed. It refers only to technical suitability and does
not absolve the user from legal obligations relating to health and safety/environment at any stage.
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3 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 1833-4, Textiles — Quantitative chemical analysis — Part 4: Mixtures of certain protein and certain other
fibres (method using hypochlorite)
ISO 2076, Textiles — Man-made fibres — Generic names
ISO 6938, Textiles — Natural fibres — Generic names and definitions
4 Terms and definitions
For the purposes of this document, the following terms and definitions given in ISO 2076 and ISO 6938 and
the following apply.
4.1
natural fibre
fibre which occurs in nature: it can be categorized according to its origin into animal, vegetable and mineral
fibre
4.2
man-made fibre
manufactured fibre
fibre obtained by a manufacturing process
4.2.1
artificial fibre
manufactured fibre made by transformation of natural polymers (macromolecular material existing in nature)
4.2.2
synthetic fibre
manufactured fibre made from synthetic polymers (macromolecular material which has been chemically
synthesised)
4.2.3
bicomponent fibre
fibre composed of two fibres forming polymer components, which are chemically or physically different or both
5 Principle
Objective: identify the fibres
Means: based on fibre properties (single or combination)
Properties for example:
• Morphology
• Solubility
• Light absorption or transmission by IR
• Burning behaviour
• Thermal behaviour
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• Colouration
• Optical behaviour
• Elemental composition
6 Apparatus and preparation of solutions
6.1 Apparatus
6.1.1 Light Microscope, using transmitted light
6.1.2 Scanning Electron Microscope
6.1.3 Bunsen Burner or other flame source
6.1.4 Infrared Spectrometer
6.1.4.1 Attenuated Total Reflection (ATR) spectroscopy device
6.1.4.2 Fourier Transform Infrared (FT-IR) spectrometer
6.1.5 Melting Point device (heated block)
6.1.6 Differential Scanning Calorimeter (DSC)
6.1.7 Thermal Gravimetric Analysis (TGA) device (thermobalance)
6.1.8 Gravimetric device (density gradient column)
6.1.9 Energy Dispersive X-ray (EDX) device
6.2 Preparation of solutions
Use only reagents of recognized analytical grade.
6.2.1 Sodium hydroxide and calcium oxide
Prepare a mixture of sodium hydroxide and calcium oxide (mass ratio of 1:1,4)
6.2.2 Iodine/potassium iodine solution
Dissolve 20 g of potassium iodide in 20 ml to 50 ml of distilled water. In this solution dissolve 2,5 g of iodine
and dilute to 100 ml
6.2.3 Zinc chloride/iodine solution
Dissolve 66 g of zinc chloride, anhydrous, and 6 g of potassium iodide in 34 ml of water.
Add a small amount of iodine crystal so that the solution is saturated.
6.2.4 Chlorine bleaching solution
Prepare the solution according to ISO 1833-4.
6.2.5 Zinc chloride/formic acid solution
Dissolve 100 g of zinc chloride, anhydrous in 100 ml of water.
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Set the density of this solution to 1,566 g/ml.
Add 6 ml of concentrated formic acid to 100 ml of this solution.
6.2.6 Sodium carbonate 0,25 % solution
Add 0,25 g of sodium carbonate to 100 ml of distilled water and dissolve.
6.2.7 Sodium hydroxide 5 % solution
Dissolve 5 g of sodium hydroxide in distilled water and dilute to 100 ml.
6.2.8 Sulphuric acid 75 % solution
Add carefully, while cooling, 700 ml of concentrated sulphuric acid (ρ 1,84 g/ml) to 350 ml of distilled water.
After the solution has cooled to room temperature, dilute to 1 l with water.
6.2.9 Chloroform/trichloroacetic acid solution
Dissolve 50 g of trichloroacetic acid in 50 g of chloroform.
6.2.10 Ethanol / potassium hydroxide solution
Dissolve 15 g of potassium hydroxide in 100 ml of ethanol.
7 Techniques
7.1 Microscopy
7.1.1 Light Microscopy
Examine the longitudinal view and/or the cross section of a fibre sample under a light microscope (6.1.1) using
transmitted light and magnification.
Compare with photomicrographs in Annex B.
7.1.2 Scanning Electron Microscopy
Examine the longitudinal view and/or the cross section of the surface of a fibre sample under a scanning
electron microscope (6.1.2) using magnification.
Compare with photomicrographs in Annex C.
7.1.3 Refractive Index
7.1.3.1 General
Refractive index governs the visibility of all colourless and transparent objects.
When a fibre is examined in air (n=1,0), the relatively large difference in refractive index between the fibre and
air causes about 5 % of the incident light to be reflected and the transmitted light to be markedly refracted.
These effects produce heavy shadows that obscure fine details of the fibre structure and can introduce
misleading identification. To reduce the degree of contrast in the shadow regions the fibres are mounted in a
medium of suitable refractive index for microscopic evaluation.
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7.1.3.2 Mounting media
If fibres are mounted in a medium of similar refractive index, surface characteristics are practically invisible but
internal structure and the presence of voids, or inclusions such as pigmentation, are clearly revealed. When it
is desired to examine the surface details of a fibre a mounting medium of significantly different refractive index
should be selected, preferably one with a much higher refractive index than that of the fibre, e.g.
1-bromonapthalene or di-iodo-methane.
Mountants should be relatively stable, and should not be volatile or react with the polymer fibre. The most
commonly used mountant is liquid paraffin which gives an image of satisfactory contrast for all fibres except
for cellulose diacetate and triacetate, for which n-decane is recommended.
It is recommended that all fibres be examined as soon after mounting as possible. Some fibres if left for a
period may be penetrated by the mountant, or they may swell which makes fibre diameter measurements
incorrect, or the mountant may evaporate.
7.1.3.3 Factors governing refractive indices
Factors governing the refractive index of fibres are the chemical nature of the molecules, the physical
arrangement of these molecules, the wavelength of incident light, moisture content, and other substances that
may be present in the fibre. In order to make accurate determinations it is necessary to use plane-polarised
light under conditions of controlled temperature and relative humidity.
Birefringent substances exhibit different indices of refraction for a given wavelength depending on the
direction of light passing through them, as well as upon its direction of transmission. For positive birefringent
fibres the maximum and minimum refractive index corresponds to the long axis of the fibres and at right
angles to the axis respectively. For negative birefringent fibres the reverse occurs.
7.1.3.4 Behaviour under polarised light
Determination of the behaviour under polarised light of a fibre can be carried out by mounting the fibre in a
mountant of known refractive index (Table 2), then viewing under polarised light such that the microscope
provides light polarised in the 6-12 o’clock direction.
Align the fibre in the direction of the light and set the microscope to provide axial illumination. Focussing
carefully on the outlines of the fibre adjust the focus to just above the fibre. For cylindrical fibres, if the
refractive index is higher than that of the mountant the fibre will act like a lens and a bright line of light will
move into the middle of the fibre as the focus is raised. If the refractive index is lower that that of the mountant
the light will flare out as the focus is raised and the middle of the fibre will become darker.
The test works best on round fibres, for flat ribbons it may be easier to see movement of a bright line at the
outlines of the fibre.
Rotating the specimen 45° and setting the microscope to provide cross polars allows birefringence to be seen.
Record if the fibre appears very bright (strong birefringence), dim (weak birefringence), or dark (no
birefringence).
Repeat the test using different mountants (see Table 2). As the refractive index of the liquid approaches that
of the fibre the fibre becomes less distinct until almost invisible. From the table match the liquid to the fibre for
identification. This technique is particularly useful for the identification of polyester.
Compare the observations made with the Table 1 to identify possible fibres.
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Table 1 — Refractive Indices of Fibres (cf. [1])
Refractive Index Birefringence
Fibre
Long n Cross n ∆n
// ┴
Diacetate 1,476 1,473 0,003 Weak
Acetate
Triacetate 1,469 1,469 0 Weak
Acrylic
1,511 1,514 -0,003 Weak, negative
Aramid
(Para-)aramid >2,000 - - -
Chrysotile 1,50 - 1,56 - varies Strong
Asbestos Amosite 1,64 – 1,69 - varies -
Crocidolite 1,68 – 1,71 - varies -
Chlorofibre 1,541 1,536 0,005 Weak
Cupro 1,553 1,519 0,034 Strong
Glass
1,52 – 1,55 - - None
Modacrylic
1,52 – 1,54 1,52 – 1,53 0,002 – 0,004 Weak
Polyamide 11 1,553 1,507 0,046 Strong
Polyamide Polyamide 6 1,575 1,526 0,049 Strong
Polyamide 6.6 1,578 1,522 0,056 Strong
Polyester 1,706 1,546 0,160 Intense
Polypropylene 1,530 1,496 0,034 Strong
Polyolefin
Polyethylene 1,574 1,522 0,052 Strong
Viscose 1,54 – 1,55 1,51 – 1,52 0,02 2– 0,039 Strong
Wool 1,557 1,547 0,010 Weak
Cotton 1,577 1,529 0,048 Strong
Silk Degummed 1,591 1,538 0,053 Strong
Flax 1,58 – 1,60 1,52 – 1,53 0,06 Strong


Table 2 — Refractive Indices of Mountants for Microscopy (cf. [1])
Mountant Refractive Index
Water 1,33
n-Heptane 1,39
Silicone Fluid (200/100,000cs) 1,406
n-Decane 1,41
Butyl stearate 1,445
Liquid Paraffin 1,47
Olive oil 1,48

a
Cedarwood oil 1,513-1,519
Anisole 1,515
Ethyl Salicylate 1,525
Methyl Salicylate 1,537
o-Dichlorobenzene 1,549
Bromobenzene 1,56
1-Bromonaphthalene 1,658
Di-iodo-methane (Methylene iodide) 1,74

a
refractive index of cedarwood oil changes with time

7.2 Flame tests
7.2.1 Burning Test
Burning fibres and assessing the characteristics of the flame and fumes given off is a classical method of
identifying a class of fibre, such as cellulosic, protein, synthetic, etc.
Present the sample, where possible, to the flame of a Bunsen burner (6.1.3) in the same physical state, e.g.
as a twisted thread, to minimise burning differences due to the physical nature of the sample
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Characteristics such as melting or shrinking from the flame should be noted. If the sample burns it should be
removed from the flame to see if it continues to burn. The nature of the residue or the odour should also be
noted.
Care must be taken in interpreting results where a mixture of fibres is present as one fibre type may mask the
presence of another. Also, the presence of finishes or coatings may give misleading results.
Results of the reaction of fibres to flame can be found in Annex A.
7.2.2 Chlorine detection test
Heat a copper wire in a Bunsen burner flame (6.1.3) until any green colouration disappears.
Remove the wire from the flame and touch the fibre with the hot end so that some adheres to it.
Again introduce the wire into the flame. The presence of chlorine in the fibre is indicated by green colour in the
flame.
NOTE 1 Chlorine containing fibres - chlorofibre, polyvinylidene and modacrylic fibres.
NOTE 2 Chlorine detection test is called “Beilstein test”.
7.2.3 Nitrogen detection test
Put a few fibres (approximately 100 mg has been found suitable) into a test tube and cover with soda lime or a
mixture of sodium hydroxide and calcium oxide (6.2.1) and heat the bottom of the test tube.
NOTE 1 A piece of cotton pad can be inserted in the tube in order to avoid any spitting.
When exposed at the opening of the tube, a wet red litmus paper will change to blue if the fibre contains
nitrogen component.
NOTE 2 Nitrogen-containing fibres: silk, wool and animal hairs, polyamide, acrylic, modacrylic, elastane, aramid and
melamine fibres.
7.3 Staining Tests
7.3.1 Colouration test with iodine/ potassium iodide solution
Observe the colouration of a fibre sample after immersion of the sample into iodine/ potassium iodide solution
(6.2.2) for 30 to 60 seconds and then washing it, and compare the observation with that in Annex A.
7.3.2 Xanthoproteic reaction
Detect protein components in a fibre.
Drop nitric acid onto a fibre sample on a slide glass under a microscope and observe the colour of the fibre. In
case yellow colour appears and it changes to orange with neutralization by ammonium, the fibre is composed
of proteins.
NOTE Silk, wool and animal hairs, and protein fibre will come under this category.
7.4 Solubility Tests
7.4.1 Polyester confirmation
In the light microscope preparation add some drops of ethanol / potassium hydroxide solution (6.2.10) to the
fibres (don’t use immersion oil or other fluid). Warm up slightly, observe in light microscope (6.1.1). Polyester
fibres changes morphologically (« hair » grows in the surface of the fibres).
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7.4.2 Cellulose confirmation
Under light microscope (6.1.1), add some drops of copper (II) ethylenediamine reagent to the fibres. Cellulosic
fibres are dissolved by this solution.
Compare with data on fibre solubility in Annex D.
7.5 Infrared Spectroscopy
7.5.1 General
The identification of polymers in general and synthetic fibres in particular can be achieved readily by this
technique, which provides an instrumental alternative to the classical tests: microscopy, solubility, and staining
tests. One great advantage of infrared examination is that the spectrum obtained is determined mainly by the
chemical constitution of the fibre and is, in general, less dependent on physical structure, variations in which
can affect the results obtained from staining, solubility, and other physical tests used for fibre identification.
Where only a few milligrams of sample are available, infrared spectroscopy is probably the most valuable
single test. The method is particularly useful with synthetic fibres such as polyolefin, aramids and acrylic
fibres, especially the latter, where the constitution and proportion of the acrylonitrile comonomer used are
frequently modified.
NOTE However, if two or more synthetic fibres are derived from the same basic monomer, whose properties have
been modified by the addition of the same comonomer in different amounts, and if the percentage difference is small, it
may not be possible to distinguish the fibres by qualitative infrared examination. Where the comonomer is different,
however, then the infrared spectrum obtained will be specific for that particular fibre.
When infrared radiation is passed through a substance, the energies of the IR photons are sufficient to cause
rotations and vibrations of molecules and atomic groups. Certain frequencies are absorbed and others are
transmitted depending on the nature of the chemical groups.
The absorption of the IR radiation by organic components consists in two main types of vibrations:
• Elongation vibrations (stretching)
• Deformation vibrations (bending)
Infrared spectroscopy, therefore, consists of determining the frequencies at which absorption occurs and
preparing a plot of percentage radiation absorbed against frequency. In practice, this is carried out
automatically by the infrared spectrometer (6.1.4).
Infrared absorption spectra are measured either with dispersive double-beam (grating) spectrophotometers or
with Fourier transform spectrometers, which give a digital interferogram that is subsequently transformed by a
computer into the recognizable infrared spectrum.
The majority of commercial spectrophotometers scan the spectrum from 2 to 15 nm, that is to say from 4000
-1 -1
to 670 cm in wavenumber.
cm
Due to the number and complexity of the absorption bands, the infrared spectrum of a given molecule is
characteristic of that compound and may be used for identification. In comparative studies of two substances,
therefore, identical infrared spectra denote identical substances.
7.5.2 Procedure
The spectra of relatively simple organic molecules are usually determined with the compound itself or in a
medium transparent to infrared radiation. Sample preparation of synthetic fibres is more complicated and, of
the several methods available, the final choice will depend on the nature of the fibre, and the individual
operator. The more suitable methods of sample preparation are described in detail.
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7.5.2.1 Pressed-disc Technique
In the pressed-disc technique, one can obtain spectra of relatively large particles that are suitable for
qualitative identification purposes, by choosing as the matrix a halide whose refractive index closely matches
that of the sample. In general, potassium bromide (n =1,56) is suitable.
D
Briefly, the method consists of mixing the finely divided fibre with finely powdered potassium bromide, which is
stored in an oven.
In preparing the disc, a few milligrams of the fibre are cut up finely with scissors. A portion of the finely
chopped or powdered material is uniformly mixed in an agate mortar with 300 mg to 500 mg of finely
powdered potassium bromide and pressed into a small disc about 1 mm thick in a suitable vacuum die under
a pressure of about 500 kPa to 750 kPa. Vacuum alone is applied to the di
...