INTERNATIONAL ISO

STANDARD 307
Third edition
1994-09-01

Plastics - Polyamides - Determination

of viscosity number

iTeh STANDARD PREVIEW

Plas tiques - Polyamides - D6 termina tion de I’indice de viscosite

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ISO 307:1994
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4e15806c3328/iso-307-1994

Reference number
ISO 307: 1994(E)
ISO 307:1994(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. Esch 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.

Draft International Standards adopted by the technical committees are

circulated to the member bodies for voting. Publication as an International
iTeh STANDARD PREVIEW
Standard requires approval by at least 75 % of the member bodies casting
a vote.

International Standard ISO

(standards.iteh.ai)
307 was prepared by Technical Committee
lSO/TC 61, Plastics, Subcommittee SC 9, Thermoplastic materjals.
ISO 307:1994
This third edition cancels https://standards.iteh.ai/catalog/standards/sist/db4de2f9-82fd-4cdb-bf83-
and replaces the second edition
(ISO 307:1984), of which it constitutes a technical revision.
4e15806c3328/iso-307-1994
Annex A forms an integral patt of this International Standard.

0 ISO 1994
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced
or utilized in any form or by any means, electronie or mechanical, including photocopying and
microfilm, without Permission in writing from the publisher.
International Organization for Standardization
Case Postale 56 l CH-l 211 Geneve 20 l Switzerland
Printed in Switzerland

ii
INTERNATIONAL STANDARD 0 ISO ISO 307:1994(E)

Plastics - Polyamides - Determination of viscosity

number

1 Scope ISO 472:1988, Plastics - Vocabulaty.

This International Standard specifies a method for the ISO 599: 1985, Plastics - Polyamide homopolymers
determination of the viscosity number of dilute sol- - Determination of matter extractable by boiling
utions of polyamides in certain specified solvents. methanol.

The method is applicable to the polyamides desig- ISO 960: 1988, Plastics - Polyamides (PA) - Deter-
nated PA 6, PA 66, PA 69, PA 610, PA 612, PA 11, mina tion 0 f wa ter content.
iTeh STANDARDISOPREVIEW
PA 12 and PA MXD6 as defined in ISO 1874-1, as
well as to copolyamides and other polyamides that are 1042:1983, Laboratory glassware - One-mark
(standards.iteh.ai)
soluble in one of the specified solvents under the
specified conditions.
volume tric flasks.

ISO 1628-1: 1984, Guidelines for the standardization

The method is not applicable to polyamides produced ISO 307:1994of methods for the determination of viscosity number
by anionic polymerization https://standards.iteh.ai/catalog/standards/sist/db4de2f9-82fd-4cdb-bf83-
of Iactams or produced with and limiting viscosity number of Polymers in dilute
crosslinking agents; such polyamides are 4e15806c3328/iso-307-1994
normally in- Solution - Part 1: General conditions.
soluble in the specified solvents.
ISO 1874-1: 1992, Plastics - Polyamide (PA) mould-
The viscosity number is determined by the general ing and extrusion materials - Part 1: Designation.
procedure specified in ISO 1628-1, observing the par-
ticular conditions specified in this International Stan- ISO 3105: -l) Glass capillary kinema tic viscome ters
dard. - Speci fica tions and Opera ting ins tructions.

The determination of the viscosity number of a ISO 3451-4:1986, Plastics - Determination of ash -
Polyamide provides a measure of the relative mol- Part 4: Polyamides.
ecular mass of the polymer.
ISO 6427:1992, Plastics - Determination of matter
extractable by organic solvents (conventional meth-
2 Normative references Ods).

The following Standards contain provisions which, ASTM D 789:1986, Standard test methods for deter-
through reference in this text, constitute provisions mination of relative viscosity, melting Point, and
of this International Standard. At the time of publi- moisture tonten t o f Polyamide (PA).
cation, the editions indicated were valid. All Standards
are subject to revision, and Parties to agreements
based on this International Standard are encouraged 3 Definitions
to investigate the possibility of applying the most re-
cent editions of the Standards indicated below. For the purposes of this International Standard, the
Members of IEC and ISO maintain registers of cur- definitions given in ISO 1628-1 and the following de-
rently valid International Standards. finition apply.

1) To be published. (Revision of ISO 3105:1976)

ISO 307:1994(E) 0 ISO

3.1 viscosity number (of a polymer): The value 5.1.3 m-Cresol, meeting the following specifi-
given by the formula cations:

appearance: clear and colourless

m-cresol content: 99 % (m/m) min.

where
o-cresol content: 0,3 % (m/m) max.
is the viscosity of a Solution of the polymer
in a specified solvent; water content: 0,13 % (m/m) max.
is the viscosity of the solvent, expressed m-CresoI of the required purity tan be obtained by
in the same units as q; distillation of chemically pure mcresol, preferably in
vacuo.
@P is the concentration, in grams per millilitre,
of the polymer in the Solution. To avoid Oxidation, nitrogen shall preferably be used
for pressure compensation. Its purity may be checked
The viscosity number is usually expressed in millilitres
by gas chromatography. The solvent shall be stored
Per gram. in a brown glass bottle.

5.2 Cleaning liquids

4 Principle
5.2.1 Chromic acid Solution, prepared by mixing
The times of flow of a solvent and a Solution of the equal volumes of sulfuric acid (e = 1,84 g/mI) and a
Polyamide at a concentration of 0,005 g/ml in the sol- saturated Solution of potassium dichromate. If re-

being used for both measurements.

iTeh STANDARD PREVIEW
vent are measured at 25 “C, the same viscometer
The viscosity
quired, the chromic acid solution may be replaced by
other, equally effective cleaning liquids.
number is calculated from these measurements (standards.iteh.ai)
and
from the known concentration of the Solution. 5.2.2 Acetone, freshly distilled.
ISO 307:1994
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6 Apparatus
4e15806c3328/iso-307-1994
5 Reagents and materials
6.1 Vacuum drying cabinet, pressure less than
Use only reagents of recognized analyt ical grad e and
100 kPa.
only distilled water or water of equivale nt purity

WARNING - Avoid contact with the skin and 6.2 Balance, accurate to 0,l mg.
inhalation of any vapours of the solvents and
cleaning liquids. 6.3 Volumetric flask, capacity 50 ml, complying
with the requirements of ISO 1042, fitted with a
ground-glass stopper.
5.1 Solvents
64. Shaking apparatus or magnetic stirrer.
5.1.1 Sulfuric acid, 96 % (m/m) + 0,15 % Im/m) sol-
ution. 6.5 Sintered-glass filter, with a pore size between
40 Pm and 100 Pm (grade P IOO), or stainless-steel
For the determination of the concentration of com- sieve, with apertures of about 0,075 mm*.
mercial sulfuric acid (95 % to 97 %) and adjustment
to 96,0 %, see annex A. 6.6 Viscometer, of the suspended-level Ubbelohde
type, complying with the requirements of ISO 3105.
5.1.2 Formic acid, 90 % (m/m) + 0,15 % (m/an) sol- The essential dimensions of the viscometer are
ution. shown in figure 1. For use with the formic acid sol-
ution (5.1.2), the inside diameter of the capillary shall
The solvent shall be stored in a brown glass bottle. Its be 0,58 mm -+ 2 % (complying with the requirements
concentration shall be checked at least evev of size No. 1 of ISO 3105). For use with the sulfuric
2 weeks. lt shall not contain more than 0,2 % acetic acid Solution (5.1 .l) or mcresol (5.1.3), the inside di-
acid or methyl formate. ameter of the capillary shall be 1,03 mm +- 2 %

2
0 ISO ISO 307:1994(E)

(complying with the requirements of size No. 2 of vent to be used, i.e. that it does not form particles of
ISO 3105). w 1.
Other types of viscometer listed in ISO 3105 may be The fraction of polymer modifier and other additives
used, provided that the results are equivalent to those that are insoluble in hydrochloric acid is determined
of the Ubbelohde viscometers specified above. How- from the hydrolysis residue (this method will form the
ever, in cases of dispute, an Ubbelohde viscometer subject of a future International Standard) and the
shall be used. correct amount of Polyamide Sample to be weighed
out is calculated using equation 8.2.
6.7 Thermostatic bath, capable of being main-
NOTE 1 Experience indicates that the usual polymer
tained at 25 “C -+ 0,05 “C. modifiers for polyamides, e.g. ethylene copolymers and EP
rubber, are so finely dispersed in the Solution of the Sample
6.8 Stop-watch, accurate to 0,l s. that the Solution viscosity is practically unaffected, provided
that the Solution is free from gel particles.

6.9 Centrifuge. If carbon fibres that tan be detected in the hydrolysis

residue under an Optical microscope are present, they
7 Preparation of test samples shall be filtered off from the Solution of the Polyamide
Sample by means of a filter crucible with a glass frit.

7.1 General 7.4 Samples with auxiliaries that are soluble

Polyamide test samples for the determination of the
in dilute hydrochloric acid and/or cannot be
viscosity number shall be completely soluble in the determined from the ash owing to Oxide
formation, e.g. carbonates, metal powders
them (reinforcement
iTeh STANDARD PREVIEW
solvents mentioned, and the additives contained in
fibres, flame-retardants and and certain Pigments
(standards.iteh.ai)
modifiers) shall not interfere with the viscosity
measurement, or it shall be possible to separate the The residue on dissolution in 90 % formic acid is de-
additives quantitatively from the Solution as with glass termined as follows:
ISO 307:1994
and carbon fibres, for instance.
Shake or stir the Polyamide Sample for several hours
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If the content of these additives is greater than at
4e15806c3328/iso-307-1994 room temperature in about 10 times its own vol-
2 % (m/m), it shall be determined quantitatively to al- ume of 90 % formic acid using the procedure de-
low the exact test Portion size to be calculated (see scribed in 10.2.
table 1).
Separate off the solid residue by filtration.
Exception: an extracted Sample if it contains extract-
Carefully wash the residue with 90 % formic acid and
able additives (see 7.2).
then with acetone. Subsequently dry for 3 h at
100 “C under a vacuum. Weigh.
7.2 Samples with extractable ingredients
7.5 Samples with auxiliaries with
The ground polymer remaining after extraction in ac- determinable ash, e.g. glass fibres and
cordante with ISO 6427 or ISO 599 shall be dried by
silicates
heating for 3 h at 100 “C under vacuum and used as
the test Sample. The ash is determined by the method specified in
ISO 3451-4, and the amount of Polyamide Sample to
7.3 Samples with auxiliaries be weighed out is calculated using equation 8.2.
(non-hydrolyzable and without ash) that are When necessary, filter the Solution of the Sample
insoluble in hydrochloric acid, e.g. polymer through a filter crucible with a glass frit before making
the measurement.
modifiers, carbon fibres and certain
flame-retardants NOTE 2 Any glass fibres of the usual dimensions con-
tained in the Sample will Sediment completely after 3 h to
Preliminary tests shall be carried out to determine 4 h. In such cases, the test Solution tan be decanted for the
whether the Sample is completely soluble in the sol- measurement and thus does not need to be filtered.
ISO 307:1994(E) 0 ISO

Table 1 - Determination of additives in Polyamide samples in Order to be able to calculate the correct
test Portion size

Additives
Property determined Test method Remarks See subclause
determinable

Extractable-matter ISO 6427; ISO 599 Low-molecular-weight Extract Sample before 7.2
content fractions measurement (thus
no correction necess-
Plasticizers at-y to size of test por-
tion)
Stabilizers

Slip agents

Hydrolysis residue (no Polymer modifiers Check solubility (if 7.3

ash) (e-g. ethylene and E/P necessary, also deter-
copolymers) mine ash and residue
on dissolution)
Carbon fibres

Organic flame-
retardants

Residue in 90 % Carbonates 7.4

formic acid Solution
(no ash) Metal powders
iTeh STANDARD
Pigments PREVIEW
(standards.iteh.ai)
Organic flame-
retardants

Ash (no Oxide conver- ISO 3451-4 ISO 307:1994 If necessary, increase
Glass fibres 7.5
sion) https://standards.iteh.ai/catalog/standards/sist/db4de2f9-82fd-4cdb-bf83-
size of test Portion
Silicates
4e15806c3328/iso-307-1994
Inorganic flame-
retardants

8 Calculation of mass of test Portion ww3 is the content of other materials (for
example other polymers such as
polyolefins, or additives, such as flame-
8.1 Polyamides with extractable matter retardants), expressed as a percentage
content not greater than 2,00 % (m/m) by mass, determined by appropriate
methods.
Calculate the mass mc, in milligrams, of the test por-
tion as follows: The corrections for w(%),, Wo and Wo need
250 only be applied if they exceed 0,5 % (dm) each.
mc =
, w(%), + w(%)* + w(%>3

where 8.2 Polyamides with extractable matter

is the water content of the Sample, ex- content greater than 2,00 % (m/.m)
ww> 1
pressed as a percentage by mass, de-
termined in accordance with ISO 960; Use the material extracted and dried according to 7.3
as the test Sample. Calculate the mass mc, in milli-
4w2 is the content of inorganic materials (for grams, of the test Portion as follows:
example fillers or glass fibres) of the
mc = 250
Sample, expressed as a percentage by
w(%)2 + w(%)3
mass, determined in accordance with 1-
ISO 3451-4; 100 - w(%)4
0 ISO ISO 307:1994(E)

figure 3. The reliability of the conversion is discussed in

13.2.
m,, w(%)2 and Wo have the same meanings
as in 8.1; 9.4 For PA 11, PA 12 and PA 11/12 copolymers,
m-cresol shall be used as solvent.
wv44 is the content of extract-
able matter of the Sample,
expressed as a percentage 9.5 For other polyamides, any of the three solvents
by mass. may be used.

lt has been assumed in this calculation that Wo and 10 Procedure

Wo have been determined on the unextracted
Sample and that the extracted and dried material will
be kept dry, so that no correction for moisture in the 10.1 Cleaning of viscometer
test Sample is required.
Clean the viscometer (6.6) Prior to the first use, again
NOTE 3 When dissolved in 50 mI of solvent, a test por- after discordant readings (for example when two
tion weighing exactly mc mg will give a Solution containing successive determinations of the efflux time of the
(almost) exactly 5 mg of polymer per millilitre. For practical solvent differ more than 0,4 s) and, further, at inter-
reasons, test Portion masses of (mc + 5) mg are allowed. vals during regular use. For this purpose allow it to
The resulting actual polymer concentration is taken into ac- stand for at least 12 h filled with a cleaning agent
count in the calculation of the viscosity number. (5.2), for example chromic acid Solution (5.2.1). Re-
move the cleaning agent, rinse the viscometer with
water, then with acetone (5.2.2) and dry, for example
9 Selection of solvent
by a slow stream of filtered air or in the vacuum dry-

9.1 iTeh STANDARD

The value of the viscosity numberof a
PREVIEW ing cabinet (6.1).

(standards.iteh.ai)
Polyamide depends on the solvent used. After each determination,
with the solvent, then
drain the viscometer, rinse
with water, followed by
Three different solvents are described in this Inter- acetone (5.2.2) and dry as described above.
national Standard: sulfuric acid Solution (5.1.1), formic ISO 307:1994
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acid Solution (5.1.2) and m-cresol (5.1.3). The flow However, if the next Solution to be measured is of a
times of the solvents shall be determined at least 4e15806c3328/iso-307-1994Polyamide of the Same type and of a similar viscosity,
once each day that they are used (see 10.3). If the it is permissible to drain the viscometer, wash it with
flow time of a solvent differs by more than 1 % from the Solution to be measured, and then fill it with this
the initial value at the time of preparation, the solvent Solution.
shall be discarded and fresh solvent prepared.
10.2 Preparation of test Solution
The solvent or solvents to be used for a particular
Polyamide are specified below. Weigh, to the nearest 0,2 mg, a test Portion of
(m, & 5) mg, where m, is the mass calculated in ac-
9.2 For PA 6, PA 66, PA 69, PA 610, PA MXD6 and cordante with clause 8, working rapidly to minimize
corresponding copolyamides, the sulfuric acid or moisture pick-up by the polymer. If the weighing
formic acid Solution shall be used as solvent, unless takes more than 2 min, reject the material and begin
these polyamides contain additives that liberate gases another weighing.
in acidic solvents, in which case m-cresol shall be
used as the solvent. Transfer the test Portion to the 50 ml volumetric flask
(6.3) and add about 40 ml of the solvent selected in
NOTE 4 Graphs for interconversion of the viscosity num- accordance with clause 9. Close the flask and Shake,
bers determined in sulfuric acid and in formic acid as solvent or stir with the magnetic stirrer (6.4), the contents
are presented in figure2. The reliability of the conversion is until the polymer has dissolved. This may take from
discussed in 13.1. approximately 0,5 h to several hours, depending on
the type of Polyamide and the particle size of the test
9.3 For PA 612 and corresponding copolyamides, Portion. When the sulfuric acid or formic acid Solution
the sulfuric acid Solution or m-cresol shall be used as is used as the solvent, the temperature shall not ex-
solvent. ceed 30 “C. When m-cresol is used as the solvent,
the temperature may be raised to 95 “C to 100 “C. If,
NOT ‘E 5 Graph s for interconversion of the v iscosity num- in the latter case, dissolution takes more than 2 h, this
bers deter mined in these two solvents are presented in shall be reported.
ISO 307:1994(E) 0 ISO

When dissolution is complete, cool the Solution to With each polyamide Sample, carry out at least two
approximately 25 “C, dilute to the mark with the sol- determinations of the viscosity number, each time
vent and mix weil. The temperature of the Solution using a fresh solution, until two successive values
during dilution shall lie between 23 “C and 27 “C. If meet the repeatability requirement corresponding to
the magnetic stirrer (6.4) is used, remove it from the the solvent used (see clause 12). Report the mean
Solution before dilution and rinse it with the solvent, of these two values, rounded off to the nearest whole
adding the rinsings to the flask before further dilution. number, as the viscosity number of the Sample.

NOTE 6 In the case of polyamides with extremely high

relative molecular masses, solutions free from the so-called
streaking phenomenon cannot always be obtained, in spite
of prolonged periods of shaking or stirring. Such test sol-
11 Expression sf results
utions may only be used for mutual comparison with similar
products. Calculate the viscosity number VN, in millilitres per
gram, from the equation:

VN =

‘IO.3 Measurement of flow times where

Filter the Solution through the sintered-glass filter is the flow time of the Solution;
(6.5) or the metal sieve into tube L of the viscometer is the flow time of the solvent;
(see figure 1). Alternatively, centrifuge the Solution at
a rotational frequency of approximately 50 s-’ and ep is the concentration of the polymer in
pour the clear supernatant liquid into the viscometer grams per millilitre of Solution.
iTeh STANDARD PREVIEW
(6.6). The volume of liquid shall be such that, after
draining, the level lies between the filling marks. NOTE 7 Density differente and kinetic energy cor-
(standards.iteh.ai)
Preferably, the filling should be done with the vis- rections tan be neglected in this method; therefore, in cal-
cometer out of the thermostatic bath (6.7) to avoid culating the viscosity number of the polymer, the ratio of
contamination of the bath in case of accidental Spills. ISO the
307:1994 viscosities of the solution and the solvent (see
clause 3) tan be replaced by the ratio of the corresponding
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times of flow. Furthermore, the concentration of the
Mount the viscometer in the thermostatic bath 4e15806c3328/iso-307-1994
main-
polymer may be expressed as grams per millilitre of solvent
tained at 25 “C k 0,05 “C, ensuring that tube N is instead of grams per millilitre of Solution, without introduc-
vertical and that the upper graduation mark, E, is at ing appreciable error.
least 30 mm below the surface of the liquid in the
bath. Allow at least 15 min for the charged viscometer
to attain the temperature of the bath.
12 Repeatability and reproducibility
Close tube M and blow or draw the liquid into the
upper bulb of tube N using a rubber bulb or similar The repeatability and reproducibility of the determi-
equipment. Close tube N. Open tube M so that the nation of the viscosity number depend on the solvent
liquid drops away from the lower end of the capillary used. The values are given in table2.
tube. Open tube N and measure the flow time, to the
nearest 0,2 s, as the time taken for the bottom of the
meniscus to pass from mark E to mark F. With cloudy
solutions, view the top of the meniscus. Repeat the 13 Interconversion of the viscosity
measurement of the flow time until two successive
values agree within 0,25 %. Take the mean of these
numbers determined in different solvents
two values as the flow time of the Solution. and interconversion of viscosity numbers
determined in 96 % sulfuric acid and
Determine the mean flow time of the solvent in the relative viscosities determined in
Same viscometer and in the same manner as that of
accordance with ASTM D 789
the Solution. Measure the solvent mean flow time
only once for each series of determinations; however,
The relation between the viscosity numbers deter-
measure the time at least once each day the solvent
mined in different solvents was determined in the
is used. If two successive determinations of the sol-
interlaboratory investigation referred to in the note to
vent mean flow time differ more than 0,4 s, clean the
table 2.
viscometer (see 10.1).
0 ISO ISO 307:1994(E)

13.2 Viscosity numbers in 96 % (dm)

Table 2 - Repeatability and reproducibility sulfuric acid and msresol, respectively
Repro- A graph of the relation between the viscosity numbers
Repeatability
Solvent ducibility
of PA 612 in sulfuric acid Solution (5.1.1) and in
OO
/ % mcresol (5.1.3) is presented in figure 3.
Sulfuric acid Solution For PA 612, the 95 % confidence interval for the dif-
2 5
(5.1 .l) ference between an actually measured value and a
Formic acid Solution
10
converted value depends on the direction of the con-
2
(5.1.2) Version. The intervals, as percentages of the con-
m-Cresol (5.1.3) 3 10 verted values, are

- value in m-cresol converted to value in

NOTE - The repeatabilities and reproducibilities were 96 % (wi/yp1)sulfuric acid: -+ 17 %
determined in an interlaboratory investigation carried out
in 1982. Seven laboratories participated in this investi- - value in 96 % (pn/m) sulfuric acid converted to
gation. The Programme included 11 samples of PA 6, 9
value in m-cresol: + 9 %
of PA 66, 3 of PA 69, 4 of PA 610, 5 of PA 612 and 2 of
PA 6(3)T. The viscosity numbers of the samples were
determined in duplicate in both solvents in accordance 13.3 Relative viscosities determined in
with this International Standard. accordance with ASTM D 789 and viscosity
numbers determined in 96 % sulfuric acid

A conversion table and a graph of the relation be-

iTeh STANDARD PREVIEW tween the relative viscosities of PA 6 and PA 66 and
the viscosity numbers of PA 6 and PA 66 in sulfuric
(standards.iteh.ai) acid Solution (5.1 .l) are presented in table 3 and
figure 4, respectively.
13.1 Viscosity numbers in 96 % (dm)
sulfuric acid and 90 % (dm) formic acid, ISO 307:1994
respectively 14 Test report
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4e15806c3328/iso-307-1994
The test report shall include the following information:
Graphs of the relation between the viscosity numbers
a) a reference to this International Standard;
of PA 6, PA 66, PA 69 and PA 610 determined in
sulfuric acid Solution (5.1 .l) and in formic acid Solution b) all details necessary for the complete identifi-
(5.1.2) are presented in figure 2. cation of the material tested;
The value measured by one laboratory in one of the c) if the Sample contains more than 0,5 % (m/m) of
solvents will, in general, differ from the value obtained other materials calculated as specified in 8.1, a
by conversion from a measurement by another labo- description of the method used for their determi-
ratory in the other solvent. The 95 % confidence in- nation
tervals for this differente, as percentages of the
converted values, are d) the solvent used;
for PA 6 + 9 % e) if longer than 2 h, the time required to dissolve a
for PA 66 +- 9 % Sample in m-cresol at 95 “C to 100 “C;
for PA 69 -+ 10% f) the viscosity number (individual values and arith-
for PA610 _+ 14% metic mean of the two determinations).
ISO 307:1994(E) 0 ISO

Table 3 - Interconversion of relative viscosity (RV) and viscosity number (VN) for PA 6 and PA 66 (values
taken from curve in figure4)

RV VN RV VN
(ISO 307) (ISO 307)
(ASTM D 789) (ASTM D 789)
(in 96 % H,SOJ (in 96 % H2S0,)

25 83,93 101 209,92

27 90,87 103 . 211,69
29 97,32 105 213,42
31 103,34 107 215,12
33 108,98 109 216,80
35 114,29 111 218,44
37 119,30 113 220,05
39 124,05 115 221,63
41 128,57 117 223,19
43 132,87 119 224,72
45 136,97 121 226,22
47 140,89 123 227,70
49 iTeh
144,65 STANDARD PREVIEW125 229,15
51 148,26 (standards.iteh.ai)
127 230,59
53 151,73 129 232,00
55 155,07 ISO 307:1994 131 233,39
57 https://standards.iteh.ai/catalog/standards/sist/db4de2f9-82fd-4cdb-bf83-
158,30 133 234,75
59 161,41
4e15806c3328/iso-307-1994 135 236,lO
61 164,42 137 237,43
63 167,33 139 238,73
65 170,15 141 240,02
67 172,88 143 241,29
69 175,54 145 242,55
71 178,12 147 243,78
73 180,62 149 245,00
75 183,06 151 246,21
77 185,44 153 247,39
79 187,75 155 248,56
81 190,Ol 157 249,72
83 192,21 159 250,86
85 194,35 161 ~ 251,99
l
87 196,45 163 l 253,ll
89 198,50 165 ~ 254,21
91 200,51 167 255,29
93 202,47 169 256,37
95 204,39 171 257,43
97 206,27 173 258,48
99 208,ll 175 259,52
 ISO 307:1994(E)

RV VN
(ISO 307)
(ASTM D 789)
(in 96 % H2S04)

177 260,54
179 261,56
181 262,56
183 263,55
185 264,53
187 265,50
189 266,46
191 267,41
193 268,35
195 269,28
197 270,20
199 271,11
201 272,Ol
203 272,91
205 273,79
207
209
iTeh STANDARD
274,67
275,54
PREVIEW
211 (standards.iteh.ai)
276,40
213 277,25
215 278,09
ISO 307:1994
https://standards.iteh.ai/catalog/standards/sist/db4de2f9-82fd-4cdb-bf83-
217 278,93 4e15806c3328/iso-307-1994
219 279,75
221 280,57
223 281,39
225 282,19
I