EN ISO 960:1997
(Main)Plastics - Polyamides (PA) - Determination of water content (ISO 960:1998)
Plastics - Polyamides (PA) - Determination of water content (ISO 960:1998)
Migrated from Progress Sheet (TC Comment) (2000-07-10): ISO 960:1998 will be replaced by the future ISO 15512 (N 117 minutes, TA/980224)+++
CEN/TC 249 Resolution 116 dated 2001-09-20 requests to withdraw this standard
Kunststoffe - Polyamide (PA) - Bestimmung des Wassergehaltes (ISO 960:1988)
1.1 Diese Internationale Norm legt Verfahren zur Bestimmung des Wassergehaltes von Polyamiden und Copolyamiden fest, die als Granulat oder Fertigartikel vorliegen. Die Verfahren sind zur Bestimmung von Wassergehalten bis hinunter zu 0,01 % (m/m) anwendbar. Von Bedeutung ist der Wassergehalt bei der Verarbeitung von Polyamiden (PA), bei der er niedrig sein sollte, um den Abbau zu verhindern, und zur Überprüfung des Feuchtegehalts von Probekörpern und Fertigartikeln.
Plastiques - Polyamides (PA) - Détermination de la teneur en eau (ISO 960:1988)
Polimerni materiali - Poliamidi (PA) - Določevanje vode (ISO 960:1988)
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN ISO 960:2000
01-maj-2000
3ROLPHUQLPDWHULDOL3ROLDPLGL 3$ 'RORþHYDQMHYRGH ,62
Plastics - Polyamides (PA) - Determination of water content (ISO 960:1998)
Kunststoffe - Polyamide (PA) - Bestimmung des Wassergehaltes (ISO 960:1988)
Plastiques - Polyamides (PA) - Détermination de la teneur en eau (ISO 960:1988)
Ta slovenski standard je istoveten z: EN ISO 960:1997
ICS:
83.080.20 Plastomeri Thermoplastic materials
SIST EN ISO 960:2000 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST EN ISO 960:2000
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SIST EN ISO 960:2000
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SIST EN ISO 960:2000
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SIST EN ISO 960:2000
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SIST EN ISO 960:2000
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SIST EN ISO 960:2000
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SIST EN ISO 960:2000
ISO 960 : 1988 (El
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, govern-
mental and non-governmental, in liaison with ISO, also take part in the work. ISO col-
laborates closely with the International Electrotechnical Commission (IEC) on all mat-
ters of electrotechnical standardization.
Draft International Standards adopted by the technical committees are circulated to
the member bodies for approval before their acceptance as International Standards by
the ISO Council. They are approved in accordance with ISO procedures requiring at
least 75 % approval by the member bodies voting.
International Standard ISO 960 was prepared by Technical Committee ISO/TC 61,
Plas tics.
lt cancels and replaces ISO Recommendation R 960 : 1969, of which it constitutes a
technical revision.
0
Jnternational Organkation for Standardkation, 1988
0
Printed in Switzerland
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SIST EN ISO 960:2000
INTERNATIONAL STANDARD
ISO 960 : 1988 (E)
Plastics - Polyamides (PA) - Determination
of water content
1 Scope 1.3 Method C is the reference method.
1.1 This International Standard specifies methods for the
2 Normative references
determination of the water content of Polyamides and
copolyamides as granules and finished articles. The methods
The following Standards contain provisions which, through
are applicable for the determination of water contents down to
reference in this text, constitute provisions of this International
0,Ol % (mlm). The water content is of importante in connec-
Standard. At the time of publication, the editions indicated
tion with the processing of PA, during which it should have a
were valid. All Standards are subject to revision, and Parties to
low value to prevent degradation, and for checking the
agreements based on this International Standard are encouraged
moisture content of test specimens and finished articles.
to investigate the possibility of applying the most recent editions
of the Standards listed below. Members of IEC and ISO maintain
1.2 Four alternative methods are specified in this Inter- registers of currently valid International Standards.
national Standard.
ISO 760 : 1978, Determination of water - Karl Fischer method
(General methodl.
Method A is an extraction method using anhydrous methanol
and titration of the water by the Karl Fischer method. lt is
ISO 3146 : 1985, Plastics -
Determination o f melting beha viour
applicable to granules having a maximum size of
fmelting tempera ture or melting range J o f semi-crys talline
4 mm x 4 mm x 3 mm and tan be used for all Polyamides
polymers.
and copolyamides.
Method B is a method of extraction by melting under vacuum
3 Method A
- Extraction with anhydrous
and titration of the water by the Karl Fischer method. lt may be
methanol
applied to granules or pieces of mouldings but not to fine
powders (particle size less than 400 Pm). For low water content
3.1 Principle
(less than 0,l % (mlm) and precise determination, it is
necessary to make a correction for the water of polyconden-
Extraction of a test Portion with anhydrous methanol and deter-
sationl). This method is not recommended when, during the
mination of the extracted water by the Karl Fischer method.
determination, due to a Change in molecular mass, additional
water is formed or existing water is bound, except when ap-
3.2 Reagents
propriate correction tan be made.
During the analysis, use only reagents of recognized analytical
Method C is a method of extraction by dissolving in a mixture
grade.
of 3-methylphenol and toluene and titration of the water by the
Karl Fischer method. lt yields results close to those obtained by
3.2.1 Methanol, anhydrous, having a water content less
method A. lt has the advantage of being applicable to granules
than 0,l % (mhd.
and powders of all sizes and to finished articles with little or no
reduction in size.
3.2.2 Karl Fischer reagent (sec 6.2).
NOTE - The three methods A, B and C differ in the procedure for
isolating the water, which is determined in all three cases by the Karl
Fischer method. 3.3 Apparatus
Ordinary laboratory apparatus and
Method D is a manometric method. The water content is
determined from the pressure increase after evaporation of the
water under vacuum. This method cannot be used for
3.3.1 Glass flasks, of capacity 250 ml, provided with ground
Polyamides polymerized with strong acids. glass or rubber Stoppers.
1) See KLINE, G.M., Analytical Chemistry of Polymers. lntersc. Puh., Part 1, p. 282 (1958).
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SIST EN ISO 960:2000
3.6 Procedure
3.3.2 Conical titration flasks, of capacity 150 ml, with stan-
dard ground necks and provided with ground glass Stoppers.
3.6.1 Carefully dry the apparatus.
3.3.3 Reflux condensers, with ground neck capable of be-
ing fitted on to the flasks (3.3.2) and on to the tubes (3.3.4).
3.6.2 Weigh the test Portion to the nearest 1 mg into a con-
ical titration flask fitted with a ground glass stopper (3.3.2); let
m be the mass, in grams, of this test Portion. Measure 50 ml of
chloride, or other
3.3.4 Tubes, straight, containing Calcium
anhydrous methanol (3.2.1) with an automatically filling pipette
means of drying, with ground joints.
(3.3.6) and add it to the conical flask containing the test por-
tion. At the same time, add 50 ml of anhydrous methanol to
3.3.5 Means for heating the flasks (3.3.2), electrically, by
another conical flask for a blank test. Stopper the flasks. Keep
hot air, or by any other suitable means.
the stoppered flasks in the desiccator (3.3.11), pending con-
tinuation of the test.
3.3.6 Automatically filling pipettes, of capacity 50 ml (see
figure 1).
3.6.3 Unstopper the flasks and quickly attach them to the
reflux condensers (3.3.3) fitted on top with the Calcium chloride
tubes (3.3.4). Boil the contents of the conical flasks under
3.3.7 Woolf bottles, with two tubes.
reflux for 3 h and leave for 45 minutes to cool to room
temperature. Separate the flasks from the condensers, quickly
3.3.8 Calcium chloride tubes, curved or U-shaped.
stopper them and place them in the desiccator.
3.3.9 Rubber bulb. 3.6.4 Titrate the contents of each f lask with the Karl Fischer
reagent as indicated in clause 6.
3.3.10 Pipette, of capacity IO ml.
4 Method B - Extraction by melting under
containing Calcium chloride or another
3.3.11 Desiccator,
vacuum
suitable drying agent.
4.1 Principle
3.3.12 Balance, accurate to 0,2 mg.
Melting of a test Portion under vacuum at a temperature ap-
proximately 30 OC above the melting Point of the resin and
3.3.13 Apparatus for determining water content by the
determination of the amount of water collected by the Karl
Karl Fischer method, in accordance with ISO 760.
Fischer method.
3.4 Preparation of test Sample
4.2 Reagents
During the analysis, use only reagents of recognized analytical
Granules
3.4.1
grade.
Place a representative test Sample of approximately 100 g in a
4.2.1 Methanol, anhydrous, having a water content less
petfectly dry glass flask (3.3.1) and immediately close the flask
than 0,I % (mlm).
with either a ground glass or a rubber stopper.
and to cool it
NOTE - It is desirable to predry the Container in an oven
4.2.2 Karl Fischer reagent (see 6.2).
absorbent, for example silica gel.
above a suitable water
4.3 Apparatus
3.4.2 Finished articles
Ordinary laboratory apparatus, and
Cut or saw the test Sample into pieces of a few millimetres
dimensions. Proceed quickly to minimize moisture absorption.
4.3.1 Vacuum melting unit, capable of maintaining a
Store the test Sample as specified in 3.4.1. pressure of less than 500 Pa*). A four-directional unit, given as
an example (see figure 2), comprises the following Parts:
3.5 Number of tests
4.3.1.1 Heating block, made up of an insulated aluminium cyl-
inder equipped with an electric heating collar having approximately
Carry out two determinations for each Sample. Use test por-
800 W power and 160 mm height. The temperature of the cyl-
tions of IO to 15 g, depending on the estimated water content.
*) 500 Pa = 5 mbar = 4 mmHg
2
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SIST EN ISO 960:2000
60 960 : 1988 EI
4.3.11 Apparatus for determining water content by the
inder is adjusted to approximately 30 OC above the melting
Karl Fischer method, in accordance with ISO 760.
Point of the resin as determined by the method specified in
ISO 3146, and maintained within + 5 OC. This cylinder, which
is 200 mm in height and 160 mm in diameter, has a central hole
4.4 Preparation of test Sample
for insertion of a thermometer (or other means of measuring
the temperature), and four holes 170 mm deep, 25 mm in
diameter and spaced at regular intervals in relation to the ver-
4.4.1 Granules
tical axis of the cylinder.
Place a representative test Sample of approximately 100 g in a
perfectly dry glass flask (4.3.5) and close the flask immediately
4.3.1.2 Four traps (P), in 6 mm x 8 mm U-shaped glass tubes
with either a ground glass stopper or a rubber stopper.
in accordance with figure 2. These Parts are inserted in a 1-litre
Dewar flask containing a mixture of methanol or acetone and
carbon dioxide ice (making it possible to obtain a temperature of NOTE - It is desirable to predry the Container in an oven and to cool it
above a suitable water absorbent, for example silica gel.
approximately - 78 OC).
4.4.2 Finished articles
4.3.1.3 Rubber vacuum tubing.
Cut or saw the test Sample into pieces of a few millimetres
4.3.1.4 Two stopcocks (Rt) and (RZ), one for each dimensions. Proceed quickly to minimize moisture absorption.
direction. Store the test Sample as specified in 4.4.1.
4.3.1.5 Four heat-proof glass tubes (A), 22 mm in
4.5 Number of tests
diameter, 220 mm in Overall length (tube plus ground Portion)
and equipped with 24/40 ground-glass sockets, to contain the
Carry out two determinations for each Sample. Use test por-
test tubes and to be inserted in the four holes provided in the
tions of
cylinder.
- IO g if the expected water content is less than 0,5 %
(mhd;
4.3.1.6 Four heat-proof glass fittings (B), equipped with
24/40 ground-glass cones. - 2 g if the expected water content is greater than 0,5 %
(lTZlm)m
4.3.2 Four glass test tubes, 16 mm in diameter and 160 mm
4.6 Procedure
long, which contain the test portions.
4.6.1 Depending on the vacuum melting unit (4.3.1) available,
4.3.3 Apparatus for producing a pressure less than
one or several determinations may be carried out simultaneous-
566 Pa in the traps.
ly. In the case of the apparatus described as an example in 4.3,
follow the procedure indicated below. For any other apparatus,
follow this procedure, taking the same general precautions.
measurement of the
4.3.4 Manometer, permitting
pressure stated in 4.3.3.
4.6.2 the glass accessories requ ired for the determination
Dw
(4.3.8) and place them in
in the oven the desiccators (4.3.9) to
250 ml, provided with ground
4.3.5 Glass flasks, of capacity
cool.
or ru bber Stoppers.
glass
4.6.3 Weigh the test Portion, to the nearest 1 mg, into a
of capacity 150 ml, with stan-
4.3.6 Conical titration f lasks,
weighed test tube (4.3.2); let m be the mass, in grams, of this
ground necks and p Irovided with ground glass Stoppers.
dard
test Portion. Seal the test tube with a completely dry rubber
stopper and replace it in the desiccator.
4.3.7 Automatic burette, of capacity IO ml.
4.6.4 Place the trap (P) in the tubing and insert it in the Dewar
flask. Evacuate the trap to a pressure of less than 500 Pa by at-
capable of being maintained at a
4.3.8 Hot-air oven,
tathing the vacuum apparatus (4.3.3) to the end of the tubing
temperature of at least 100 OC.
and opening stopcock (RZ), stopcock (RI) being ctosed. Wait
5 min to allow the trap to resch a temperature of about
-78 OC. Place the test tube, after removing its stopper, in a
of containing all of the glassware
4.3.9 Desiccators, capable
ground tube (A). Close the ground tube (A) with a glass fitting
needed in the determination.
(B) and join to the trap by rubber vacuum tubing and stopcock
(R,). Open stopcock (Rt) and check that the pressure is less
than 500 Pa by reading the manometer (4.3.4).
4.3.10 Balance, accurate to 0,2 mg.
3
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SIST EN ISO 960:2000
ISO 960 : 1988 CE-I
5.3.2 Conical titration flask, of capacity 250 ml, with stan-
4.6.5 Place the ground tube for 30 min in the heating block,
dard ground neck and provided with a ground glass stopper.
previously brought to the required temperature (about 30 OC
above the melting Point as determined by the method specified
in ISO 3146), while the vacuum apparatus is continuously func-
5.3.3 Reflux condenser, with ground neck, capable of being
tioning. Glose stopcocks (RZ) and (Rt) and shut off the vacuum
fitted on the flask (5.3.2) and on to the tube (5.3.4
...
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