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1、b7b-75 4853903 0070239 2 INTERNATIONAL STANDARD INTERNATIONAL ORGANIZATION FOR STANDARDIZATION eMEXAYHAPOAHAII OPTAHi3AUMR no CTAHAAPTMJAUMM *ORGANISATION INTERNATIONALE DE NORMALISATION Surface active agents - Measurement of foaming power - Modified Ross-Miles method Agents de surface - Mesurage du
2、 pouvoir moussant - Mthode de Ross-Miles modifie First edition - 1975-07-01 UDC 661.185 : 532.69 : 66.069.85 Ref. No. IS0 696-1975 (E) Ln r- z Descriptors : surfactants, tests, measuring, foaming power. i, a C o -_- - - 8 P - - - t Price based on 5 pages /I /. -1 f L / . . i Copyright International
3、Organization for Standardization Provided by IHS under license with ISO Licensee=NASA Technical Standards 1/9972545001 Not for Resale, 04/27/2007 20:06:30 MDTNo reproduction or networking permitted without license from IHS -,-,- FOREWORD IS0 (the International Organization for Standardization) is a
4、worldwide federation of national standards institutes (IS0 Member Bodies). The work of developing International Standards is carried out through IS0 Technical Committees. Every Member Body interested in a subject for which a Technical Committee has been set up has the right to be represented on that
5、 Committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. Draft International Standards adopted by the Technical Committees are circulated to the Member Bodies for approval before their acceptance as International Standards by the IS
6、0 Council. International Standard IS0 696 was drawn up by Technical Committee ISO/TC 91, Surface active agents. It was submitted directly to the IS0 Council, in accordance with clause 6.1 1 of the Directives for the technical work of ISO. This International Standard cancels and replaces R696-1968, w
7、hich had been approved by the Member countries : IS0 Recommendation Bodies of the following Austria Belgium Brazil Canada Chile Czechoslovakia France Germany Greece Hungary Ireland Israel Italy Japan Korea, Rep. of Netherlands New Zealand Poland Portugal Romania South Africa, Rep. of Spain Sweden Sw
8、itzerland Turkey Egypt, Arab Rep. of United Kingdom U.S.S. R. Yugoslavia No Member Body had disapproved the Recommendation. O International Organization for Standardization, 1975 6 Printed in Switzerland Copyright International Organization for Standardization Provided by IHS under license with ISO
9、Licensee=NASA Technical Standards 1/9972545001 Not for Resale, 04/27/2007 20:06:30 MDTNo reproduction or networking permitted without license from IHS -,-,- INTERNATIONAL STANDARD IS0 696-1975 (E) Surface active agents - Measurement of foaming power - Modified Ross-Miles method O INTRODUCTION The me
10、thod specified in this International Standard makes it possible to check one of the characteristics of surface active agents which it is important to take into account in order to assess their potential use. The precisely defined conditions specified for this method do not necessarily correspond to
11、practical conditions of use. Consequently, the results obtained do not necessarily provide information regarding the behaviour of products under actual conditions of application. The use of this method, and the assessment of the results obtained, must therefore depend upon the aims sought after. In
12、particular, application of the method to products having a low foaming power may lead to results which have no practical interest. 1 SCOPE This International Standard specifies a method of measurement of the foaming power of a surface active agent. 2 FIELD OF APPLICATION The method is applicable to
13、all surface active agents. Measurement of the foaming power of solutions of readily hydrolysable agents, however, does not give reliable results, as the hydrolysis products collect in the films of liquid and affect the persistence of the foam. NOTE - The persistence of liquid films is very sensitive
14、 to the presence of particles of insoluble matter. This method of measurement of foaming power should be used only with the greatest of care, therefore, for measuring the foaming power of compositions based on surface active agents of which solution is rarely complete. Foaming power is also very sen
15、sitive to small variations in composition. Consequently, the results obtained on formulated products should be interpreted with caution. The method is not applicable for measurement of the foaming power of very dilute solutions of surface active agents, such as river waters containing surface active
16、 agents. 1) In preparation. (Revision of ISO/R 607.) 21 In preparation. 3) Definition taken from ISOIR 862. 3 REFERENCES IS0 607, Surface active agents - Detergents - Methods of sample division. 1 ) ISO/R 862, Surface active agents - Glossary. ISOIR 1042,One-mark volumetric flasks. IS0 2174, Surface
17、 active agents - Preparation of water with known calcium hardness. IS0 . . ., Graduated measuring cylinders.2) 4 DEFINITIONS 4.1 foaming power : The ability to produce foam.3) NOTE - In this International Standard, foaming power is characterized by the volume of foam obtained under specific experime
18、ntal conditions. The decay of this volume of foam during the 5 min following its formation is also relevant. 4.2 foam : A mass of gas cells separated by thin films of liquid and formed by the juxtaposition of bubbles, giving a gas dispersed in a liquid.3) 5 PRINCIPLE Measurement of the volume of foa
19、m obtained after running 500 ml of a solution of a surface active agent, from a height of 450 mm, on to a liquid surface of the same solution. 6 APPARATUS Ordinary laboratory apparatus, and 6.1 Test apparatus 6.1.1 Components of apparatus (see figures 1 and 2) 6.1.1.1 Separating funnel of 1 I capaci
20、ty, consisting of a spherical bulb joined to the. upper end of a tube about 200 mm long, having a tap a t the lower end. The separating funnel carries a mark, 150 mm above the axis of the tap, Copyright International Organization for Standardization Provided by IHS under license with ISO Licensee=NA
21、SA Technical Standards 1/9972545001 Not for Resale, 04/27/2007 20:06:30 MDTNo reproduction or networking permitted without license from IHS -,-,- - - _ _ _ l- b7b-75 4851703 0070242 2 which indicates the lower limit of discharge during the test. The lower end of the tube is cut off strictly perpendi
22、cular to its length, 40 mm below the axis of the tap. The tap is moulded, not blown, the hole through the key being of sufficient diameter (not less than 3 mm) to avoid undue obstruction of the flow of the liquid. 6.1.1.2 Measuring cylinder of 1 I capacity, complying with ISO ., with graduations at
23、each 10 ml. The measuring cylinder stands in a water bath fitted with a thermostat, the bath being sufficiently large to accommodate the measuring cylinderimmersed up to half its height. 6.1.1.3 Stand comprising a vertical rod, sufficiently long to allow the separating funnel and the measuring cylin
24、der to be held in place. To ensure that the assembly is centred and so maintained during the measurement, the separating funnel is held by means of a ring supporting the spherical part, and a clamp placed as low as possible around the stem of the separating funnel, near the tap. The measuring cylind
25、er is held in place by means of a screw-clamp with one movable jaw. 6.1.1.4 Metering tube, stainless steel, 70 mm long, 1,9 f 0,02 mm internal diameter and 0,3 mm wall thickness. The ends of the tube shall be cut accurately at right angles to the axis of the tube, on a precision tool lathe. The mete
26、ring tube is a push fit in a steel mounting tube 5 to 10 mm long, of internal diameter equal to the external diameter of the metering tube, and of external diameter equal to that of the low end of the glass tube of the separating funnel. The upper ends of the metering tube and of the mounting tube s
27、hall be in the same plane. The mounting tube is fixed by means of a short length of thick rubber tube (vacuum tubing) so that the upper end of the mounting tube is in contact with the lower end of the glass tube. 6.1.2 Cleaning of apparatus Perfect cleanliness of the apparatus is essential for the s
28、uccess of the test. Before the test and, if possible, overnight, leave all glassware in contact with chromic-sulphuric acid mixture, prepared by slowly stirring concentrated sulphuric acid (pz0 1,83 g/ml) into an equal volume of a saturated solution of potassium dichromate. Rinse the apparatus first
29、 in distilled water until free from acid and then with a small quantity of the solution under test. Keep the mounting tube and metering tube assembly for 30 min in the vapour of an azeotropic mixture of ethanol and trichlorethylene, then rinse it with a small quantity of the solution under test. Bet
30、ween successive measurements, on the same product, simply rinse the apparatus with the solution under test. When it is required to remove the foam remaining in the measuring cylinder, no matter what method is employed to do so, follow by a rinse with the solution under test. 2 - - 6.2 Graduated meas
31、uring cylinder, capacity 500 mi. 6 . 3 Graduated measuring cylinder, or pipette, capacity 50 ml. 6.4 Volumetric flask, capacity 1 O00 ml, complying with ISO/R 1042. 7 SAMPLING The laboratory sample of surface active agent shall be prepared and stored by the procedures specified in IS0 607. 8 PREPARA
32、TION OF THE TEST SOLUTION Prepare, from the laboratory sample, a solution of the material at its working strength. The water used for dilution may be either distilled water saturated with air by bubbling, or hard water containing 6 meq of calcium(l1) ions per litre (see IS0 2174). Prepare the soluti
33、on by pasting and then dissolution in the water chosen, previously warmed to 50C. It is necessary to mix very gently to prevent the formation of foam. Keep the solution at 50 +- 2 OC without stirring, until the test is made. The age of the solution, at the time of the measurement, shall be not less
34、than 30 min and not greater than 2 h. Other conditions than those specified above (for example, hardness of the water, temperature) may be chosen provided that they are mentioned in the test report. 9 PROCEDURE 9.1 Assembly of apparatus The apparatus shall be assembled in a place free from draughts.
35、 Adjust the thermostat of the water bath to bring the temperature of the bath to 50 f 2 C. Introduce 50 ml of the solution, prepared as described in clause 8, into the measuring cylinder (6.1.1.21, running it down the inside wall so that no foam is formed on the surface. Place the measuring cylinder
36、 in the water bath and hold it in place by means of the screwclamp. Mount the separating funnel (6.1.1.1) with the metering tube (6.1.1.4) attached and adjust the support (6.1.1.31, so that the axes of the measuring cylinder and the metering tube coincide, and also that the lower end of the metering
37、 tube is 450 mm above the level of the 50 ml of solution in the measuring cylinder. Copyright International Organization for Standardization Provided by IHS under license with ISO Licensee=NASA Technical Standards 1/9972545001 Not for Resale, 04/27/2007 20:06:30 MDTNo reproduction or networking perm
38、itted without license from IHS -,-,- 4B5L703 0070243 4 IS0 696-1975 (E) 676-75 9.2 Filling the apparatus For the first measurement, introduce part of the test solution into the separating funnel up to the 150 mm mark. To do this, immerse the lower end of the metering tube in a portion of the test so
39、lution maintained at 50k 2 O C in a small beaker and aspirate the liquid by suitable means attached to the top of the separating funnel. This is the most certain way to avoid the formation of air-bubbles in the hole through the key of the tap. Keep the small beaker below the separating funnel until
40、the measurement is made. To complete the filling, pour 500 ml of the test solution, maintained a t 50 f 2 OC, into the separating funnel from the 500 ml graduated measuring cylinder (6.2), performing this operation gently to avoid the formation of foam. This may be achieved by the use of a special f
41、unnel with a curved stem, the end of which touches the interior wall of the separating funnel. For subsequent measurements, empty the separating funnel down to a height of 10 to 20 mm above the tap. Place the beaker full of the test solution, kept at 50 f 2 O C , under the separating funnel as befor
42、e. Fill the Separating funnel with the test solution up to the 150mm mark, then pour in 500 ml of the test solution, maintained at 50 f 2 OC, as described above. NOTE - Filling to the 150 mm mark may also be achieved by not allowing the separating funnel to empty completely after the previous fillin
43、g with the test solution. This simpler method gives less guarantee of freedom from air bubbles. 9.3 Measurement Allow the solution to flow, without interruption, until the level falls to the 150 mm mark. Note the time of efflux. All measurements in which the time of efflux differs by more than 5 % f
44、rom the arithmetic mean of observed efflux times should be neglected, an abnormally long time indicating the presence of an air-bubble in the metering tube or in the tap. Measure the volume of foam (only the foam) 30s, 3 min and 5 min after the efflux has been stopped. If the upper level of the foam
45、 has a depression in the centre, record the reading as the arithmetic mean between the centre and the edges. Carry out ten measurements, preparing a fresh solution each time as described in clause 8. Take the arithmetic mean of at least eight results. 10 EXPRESSION OF RESULTS Express the results in
46、millilitres of foam formed 30 s, 3 min and 5 min after stopping the efflux. If necessary draw the corresponding curve. 11 TEST REPORT The test report shall contain the following information : a) all information necessaty for complete identification of the sample; b) the concentration of the test sol
47、ution, expressed in grams of surface active agent per litre; c) the temperature, in degrees Celsius, during the test, if it is different from that recommended2); d) the hardness of the water actually used, expressed in milligram equivalents of calcium(ll) ions per litre, if this differs from that re
48、commended; e) the results, and the method of expression used; fl the reference of the method used; g) all operating details not covered by this International Standard, or any which are optional, as well as any other factors that may have affected the results. 1) It may be of assistance, in making th
49、is measurement, to use a white varnished slip carrying a longitudinal black varnished line. This slip is placed parallel to the axis of the receiving cylinder, and the lower level of the volume of foam to be measured is taken at the point where contrast between black and white is visible. 2) Curves showing the relation between foaming power and temperature of different products can vary considera