1、November 2008DEUTSCHE NORM English price group 8No part of this standard may be reproduced without prior permission ofDIN Deutsches Institut fr Normung e. V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany,has the exclusive right of sale for German Standards (DIN-Normen).ICS 83.040.10; 83.080.01!$
2、Rw“1478499www.din.deDDIN ISO 1409Plastics/rubber Polymer dispersions and rubber latices (natural and synthetic) Determination of surface tension by the ring method (ISO 1409:2006)English version of DIN ISO 1409:2008-11Kunststoffe/Kautschuk Polymerdispersionen und Kautschuklatices (natrliche und synt
3、hetische) Bestimmung der Oberflchenspannung mit dem Ringverfahren (ISO 1409:2006)Englische Fassung DIN ISO 1409:2008-11SupersedesDIN ISO 1409:1999-07www.beuth.deDocument comprises 10 pages2 Contents Page National foreword 2 National Annex NA (informative) Bibliography 3 1 Scope 4 2 Normative referen
4、ces 4 3 Principle5 4 Reagents.5 5 Apparatus .5 6 Sampling.5 7 Procedure .5 7.1 Preparation of apparatus 5 7.2 Calibration 5 7.3 Preparation of the test sample .6 7.4 Determination.6 8 Expression of results 7 8.1 Calibration against standard mass7 8.2 Calibration against a standard liquid 8 9 Test re
5、port 8 Annex A (informative) Precision of the test method .9 Annex B (informative) Correction factors 10 National foreword This standard has been prepared by Technical Committee ISO/TC 45 “Rubber and rubber products” (Secretariat: DSM, Malaysia), Subcommittee SC 2 “Testing and analysis” (Secretariat
6、: SIS, Sweden). The responsible German body involved in its preparation was the Normenausschuss Materialprfung (Materials Testing Standards Committee), Technical Committee NA 062-04-32 AA Prfung von Latex. The text of ISO 1409:2006 has been adopted in this standard without any modification. It shoul
7、d be noted that there is an error in ISO 1409:2006, subclause 5.3 “Thermostatic bath”: The temperature for tropical countries should read (27 1) C instead of (27 + 1) C. The DIN Standards corresponding to the International Standards referred to in this document are as follows: ISO 123 DIN ISO 123 IS
8、O 124 DIN 53563 ISO 705 DIN ISO 705 ISO 255 DIN EN ISO 2555 ISO 321 DIN EN ISO 3219 ISO 3696:1987 DIN ISO 3696 DIN ISO 1409:2008-11 3 Amendments This standard differs from DIN ISO 1409:1999-07 as follows: a) Clause 2 “Normative references” has been updated. b) The standard has been editorially revis
9、ed. c) In the German version, the correction index in Table B.2 has been corrected. d) The content of ISO 1409:2006 has been adopted in full. Previous editions DIN ISO 1409: 1999-07 DIN 53593: 1980-01 National Annex NA (informative) Bibliography DIN 53563, Testing of latex Determination of total sol
10、ids content DIN EN ISO 2555, Plastics Resins in the liquid state or as emulsions or dispersions Determination of apparent viscosity by the Brookfield test method DIN EN ISO 3219, Plastics Polymers/resins in the liquid state or as emulsions or dispersions Determination of viscosity using a rotational
11、 viscometer with defined shear rate DIN ISO 123, Rubber latex Sampling DIN ISO 705, Rubber latex Determination of density between 5 C and 40 C DIN ISO 3696:1991, Water for analytical laboratory use Specification and test methods DIN ISO 1409:2008-11 Plastics/rubber Polymer dispersions and rubber lat
12、ices (natural and synthetic) Determination of surface tension by the ring method WARNING Persons using this International Standard should be familiar with normal laboratory practice. This standard does not purport to address all of the safety problems, if any, associated with its use. lt is the resp
13、onsibility of the user to establish appropriate safety and health practices and to ensure compliance with any national regulatory conditions. 1 Scope This International Standard specifies a ring method for the determination of the surface tension of polymer dispersions and rubber latices (natural an
14、d synthetic). The method is valid for polymer dispersions and rubber latices with a viscosity less than 200 mPas. To achieve this, the dispersion or latex is diluted with water to a mass fraction of total solids of 40 %. If necessary, the solids content is further reduced to ensure that the viscosit
15、y is under the specified limit. The method is also suitable for prevulcanized latices and compounded materials. 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 referenc
16、es, the latest edition of the referenced document (including any amendments) applies. ISO 123, Rubber Iatex Sampling ISO 124, Latex, rubber Determination of total solids content ISO 705, Rubber latex Determination of density between 5 C and 40 C ISO 1652, Rubber latex Determination of apparent visco
17、sity by the Brookfield test method ISO 2555, Plastics Resins in the liquid state or as emulsions or dispersions Determination of apparent viscosity by the Brookfield Test method ISO 3219, Plastics Polymers/resins in the liquid state or as emulsions or dispersions Determination of viscosity using a r
18、otational viscometer with defined shear rate ISO 3696:1987, Water for analytical laboratory use Specification and test methods 4 DIN ISO 1409:2008-11 3 Principle A horizontally suspended ring of thin wire is attached to a “du Nouy“ type tensiometer and immersed in the liquid under test, then slowly
19、pulled out. Just before the ring detaches itself from the surface of the liquid, the force required reaches a maximum. This force is measured by a torsion balance, inductive pick-up or some other suitable measuring device. 4 Reagents 4.1 Distilled water, carbon-dioxide-free, or water of equivalent p
20、urity (grade 3 as defined in ISO 3696:1987). 4.2 Toluene, of recognized analytical purity. 5 Apparatus 5.1 Tensiometer (du Nouy type), with a platinum or platinum-iridium alloy ring of either 60 mm or 40 mm nominal circumference (corresponding to 9,55 mm or 6,37 mm internal radius, respectively) and
21、 made of wire having a nominal radius of 0,185 mm. 5.2 Glass dish or vessel, of 50 cm3capacity, with an internal diameter of at least 45 mm. 5.3 Thermostatic bath, or some other means of adjusting the temperature of the test sample to NOTE The temperature coefficient of rubber latices over the tempe
22、rature range 20 C to 30 C is 0,1 mN/m per degree Celsius. 6 Sampling Carry out the sampling in accordance with one of the methods specified in ISO 123. 7 Procedure 7.1 Preparation of apparatus Clean the dish or vessel (5.2) carefully, since any contamination may lead to variable results. Clean the r
23、ing of the tensiometer (5.1) by washing in water (4.1) and then heating in the oxidizing section of a Bunsen or methanol flame. Take extreme care to avoid touching or distorting the tensiometer ring when handling it; ensure that the ring remains parallel to the surface of the liquid during the deter
24、mination. Failure to observe these precautions will lead to inaccurate results. 7.2 Calibration Carefully calibrate the tensiometer scale against a standard mass or a reference liquid such as distilled water (4.1) or toluene (4.2) in accordance with the manufacturers instructions, so that the scale
25、will read in millinewtons per metre. NOTE Calibration is generally carried out against a standard mass. It should be noted that the calculation of the results (see Clause 8) requires different correction factors depending on the method of calibration. 5 DIN ISO 1409:2008-11 23 C 1 C (27 C + 1 C for
26、tropical countries) . N1)N1)National footnote: See National foreword. 7.3 Preparation of the test sample 7.3.1 If the total solids content of the test sample of latex or polymer dispersion is not known, determine it in accordance with ISO 124. If the mass fraction of solids is greater than 40 %, dil
27、ute the test sample to a mass fraction of total solids of 40 % 1 % with water (4.1). If it is suspected that the viscosity of the diluted test sample is still greater than 200 mPas, determine it by the appropriate method (ISO 1652, ISO 2555 or ISO 3219). If necessary, dilute the test sample further
28、until the viscosity is less than 200 mPas, noting the final solids content. NOTE Dilution to a mass fraction of 40 % has a negligible effect on the surface tension of polymer dispersions and rubber latices. In some cases, the surface tension at a higher solids content may be required, in which case
29、this may be measured by the method as specified with little loss of accuracy, provided that the viscosity is less than 200 mPas. If the density of the diluted test sample of latex or polymer dispersion is not known, determine it in accordance with ISO 705. 7.3.2 Using the thermostatic bath (5.3), ad
30、just the temperature of the diluted test sample to 23 C 1 C (or 27 C 1 C in tropical countries). 7.3.3 Remove approximately 25 cm3of the diluted test sample, using a pipette with its tip well below the surface of the liquid, and transfer it to the dish or vessel (5.2). Remove any air bubbles from th
31、e surface of the sample by wiping with a piece of hard filter paper. Measure the surface tension immediately to avoid errors due to the formation of surface skin. 7.4 Determination With the tensiometer protected from air currents, place the dish or vessel containing the diluted test sample on the ad
32、justable platform of the instrument beneath the ring of the tensiometer. Adjust the instrument, following the manufacturers guidelines, so that the beam is in the balance position when the ring is dry and the scale reading is zero. Raise the platform until the liquid makes contact with the ring and
33、then immerse the ring to a depth of approximately 5 mm. Slowly lower the platform by means of the platform-adjusting screw, and simultaneously increase the torsion in the wire, proportioning these two adjustments so that the beam remains exactly in its balance position. As the film adhering to the r
34、ing approaches its breaking point, proceed very slowly with adjustments. For determinations with an automatic tensiometer, regulate the penetration depth of the ring to approximately 5 mm below the surface of the liquid and adjust the rate of movement of the dish or vessel to 10 mm/min. Record the m
35、aximum scale reading just prior to the point at which the ring separates from the dispersion or latex (this is of particular importance with undiluted latices or polymer dispersions of high viscosity). Immediately raise the dish again before the film breaks, re-submerging the ring. Repeat the determ
36、ination three times for a total of four determinations. Should the film break, clean the ring as described in 7.1 and repeat the determination. Discount the first reading and record the average of the next three readings, which should agree to within 0,5 mN/m of the median value. 6 DIN ISO 1409:2008
37、-11 8 Expression of results 8.1 Calibration against standard mass If (as is usual) the tensiometer has been calibrated against a standard mass, the reading () must be corrected by a factor depending on the dimensions of the ring and the density of the liquid: M F = where M is the scale reading, in m
38、illinewtons per metre; F is the factor calculated from the equation 20,036780,725MF PR =+ + in which R is the mean radius, in millimetres; is the density, in megagrams per cubic metre, of the liquid; P is a constant calculated from the equation 1,6790,045 34rPR= where r is the radius, in millimetres
39、, of the wire. NOTE 1 Some formulae for calculating F include the gravitational constant G. This has been incorporated directly into the constant 0,036 78 to avoid possible confusion over units. NOTE 2 For standard rings of 60 mm or 40 mm nominal circumference (R = 9,55 mm or 6,37 mm, respectively)
40、and wire of nominal radius 0,185 mm, P will be given by 600,012 82P =+ or 400,003 43P = NOTE 3 “Surface tension” and “surface free energy” are synonymous and have equal numerical values when expressed in millinewtons per metre and millijoules per metre squared, respectively. NOTE 4 Since it may not
41、be practical to calculate the factor F separately for each sample tested, it is convenient to create tables for a correction index depending on the wire dimensions (see Annex B). 7 DIN ISO 1409:2008-11 8.2 Calibration against a standard liquid If the calibration has been carried out using a referenc
42、e liquid, then the surface tension , expressed in millinewtons per metre, is given by: M F= where M is the reading for the diluted test sample, in millinewtons per metre, on the scale calibrated with the reference liquid; F is a factor calculated from the equation/F FM= in which F is calculated as i
43、n 8.1; is the known surface tension of the reference liquid; M is the actual scale reading recorded for the reference liquid. It is particularly important to read the equipment manufacturers instructions carefully if using this procedure, as some corrections may have been built into the equipment. F
44、or this reason, calculated corrections are not given in Annex B. 9 Test report The test report shall include the following information: a) a reference to this International Standard; b) all details necessary for the identification of the sample tested; c) the temperature at which the test was carrie
45、d out; d) the solids content of the test sample originally, and as tested after dilution; e) the results and the units in which they have been expressed; f) any usual features noted during the determination; g) the date and place where the determination was carried out; h) any operation not included
46、 in this International Standard or in the International Standards to which reference is made, as well as any operation regarded as optional. 8 DIN ISO 1409:2008-11 Annex A (informative) Precision of the test method With accurate operation and control, i.e. correctly following the details of the proc
47、edure, it is possible to obtain the following: repeatability limit: 1,0 mN/m reproducibility limit: 2,0 mN/m NOTE The work to generate the precision data was initiated before the publication of lSO/TR 9272:1986, Rubber and rubber products Determination of precision for test method standards. Consequ
48、ently the results are not expressed in the recommended format. 9 DIN ISO 1409:2008-11 Annex B (informative) Correction factors The calculation of correction factors for each individual evaluation is time consuming. Where tensiometers with electronic data processing are used, the results may be autom
49、atically corrected. If this is not practical, it is suggested that it is more convenient to express the correction factors F as correction indices that can be subtracted from the scale reading M: M = rather than M F = Tables B.1 and B.2 contain such correction indices for rings with 40 mm and 60 mm circumference and a mean radius of the wire of 0,185 mm. Table B.1 Correction index , for 40-mm-circumference tensiometer ring, to be subtracted from the scale
