इंटरनेट मानक Disclosure to Promote the Right To Information Whereas the Parliament of India has set out to provide a practical regime of right to information for citizens to secure access to information under the control of public authorities, in order to promote transparency and accountability in the working of every public authority, and whereas the attached publication of the Bureau of Indian Standards is of particular interest to the public, particularly disadvantaged communities and those engaged in the pursuit of education and knowledge, the attached public safety standard is made available to promote the timely dissemination of this information in an accurate manner to the public. “जान1 का अ+धकार, जी1 का अ+धकार” “प0रा1 को छोड न’ 5 तरफ” Mazdoor Kisan Shakti Sangathan Jawaharlal Nehru “The Right to Information, The Right to Live” “Step Out From the Old to the New” IS 13360-11-10 (1999): Plastics - Methods of Testing, Part 11: Special Properties, Section 10: Resins in the Liquid State or as Emulsions or Dispersions - Determination of Apparent Viscosity by the Brookfield Test Method [PCD 12: Plastics] “!ान $ एक न’ भारत का +नम-ण” Satyanarayan Gangaram Pitroda ““IInnvveenntt aa NNeeww IInnddiiaa UUssiinngg KKnnoowwlleeddggee”” “!ान एक ऐसा खजाना > जो कभी च0राया नहB जा सकता हहहहै””ै” Bhartṛhari—Nītiśatakam “Knowledge is such a treasure which cannot be stolen” IS 13360 (Part 1 l/Set 10) : 1999 IS0 2555 : 1969 Indian Siandard SCITSALP - METHODS FO GNITSEmT PART 11 SPECIAL PROPERTIES Section 10 Resins in the Liquid State or as Emulsions or Dispersions - Determination of Apparent Viscosity by the Brookfield Test Method ICS 83.080; 17.060 0 SIB 9991 BUREAU OF tNDIAN STANDARDS MANAK BHAVAN,~9 BAHADUR SHAH RAFAZ MARG NEW IHLED 200011 February 9991 Price Group 4 sdohteM of tseT for scitsalP lanoitceS ,eettimmoC PCD 32 LANOITAN FOREWORD sihT naidnI dradnatS ( traP 1 teS/l 01 ) hcihw si lacitnedi htiw 0SI 5552 : 9891 scitsalP‘ - sniseR ni eht diuqit etats ro sa snoislume ro snoisrepsid- - noitanimreteD of tnerappa ytisocsiv yb eht , dleifkoorB tset ’dohtem deussi yb eht lanoitanretnI noitazinagrO for noitazidradnatS ( 0SI ) saw m detpoda yb eht uaeruB of naidnI sdradnatS no eht noitadnemmocer of sdohteM of tseT for scitsalP lanoitceS eettimmoC dna lavorppa of eht ,muelorteP laoC dna detaleR stcudorP noisiviD .licnuoC ehT txet of 0SI dradnats sah neeb devorppa sa elbatius for noitacilbup sa naidnI dradnatS tuohtiw .snoitaived niatreC snoitnevnoc ,era ,revewoh ton lacitnedi ot esoht desu ni naidnI .sdradnatS noitnettA si ylralucitrap nward ot eht :gniwollof )a reverehW eht sdrow lanoitanretnt‘ raeppa’dradnatS gnirrefer ot siht ,dradnats yeh? dluohs eb daer sa naidnI‘ .’dradnatS )b Comma ),( sah neeb desu sa a lamiced rekram elihw ni naidnI ,sdradnatS eht tnerruc ecitcarp si ot esu a tniop ).( sa eht lamiced .rekram gnitroper~nl eht stluser of a tset ro sisylana edam ni ecnadrocca htiw siht ,dradnats if eht lanif ,eulav devresbo ro ,detaluclac si ot eb dednuor off, ti llahs eb enod ni ecnadrocca htiw SI 2 : 0691 seluR‘ for gnidnuor off laciremun seulav ( .‘)desiver IS 13360 (Part ll/Sec 10) : 1999 IS0 2556 : 1969 Indian Standard SCITSALP - METHODS 0-F GNITSET PART 11 SPECIAL PROPERTIES Section 10 Resins in the Liquid State or as Emulsions or Dispersions - Determination of Apparent Viscosity by the Brookfleld Test Method 1 scope The detailed working principle of this apparatus, its descnption and the characteristics of the three types are given in annex B. Thii International Standard specifies a method of determining an apparent viscosity, by the Brookfield Test method, of resins Each viscometer consists of: in a liquid or similar state, using one of the types of rotational -~ the viscometer body; viscometer described in this Standard. - seven interchangeable spindles numbered from 1 to 7 The application of this method to specific products is detaited (number 1 being the largest); these spindles carry a mark in annex A. that indicates the immersion level in the liquid; they are Ihe same for the three types of viscometer; do not use spindles The viscometers, types A, 6 and C, permit viscosity measure- which show signs of corrosion or eccentricity; ments from 0,02 Pams( 20 cP) to 60 000 Pa-s 60 x lo6 CP). - a detachable guard stirrup (type A only). 2 Principle The rotational frequencies available on the different types of Brookfield viscometer are given in table 1. A spindle, of cylindrical or related form (disc), is driven at a NOTE - In the ceee of the Brookfield apparatus, the relationship be- constant rotational frequency in the product being studied. tween the models and available frequencies and viscometer typee A, B and C are given in table 1. Other rotational frequencies within the same The resistance exerted by the fluid on the spindle, which ’ limits may be chosen. depends on the viscosity of the product, causes a torque which is indicated by a suitable mater. This mea surement may be based on tightening of a spiral spring dependin g on the torque, Table 1 - Rotational frequencies available for the three indicated by the movement of a needle on a dial. types of viscometer I (y;y“ The apparent Viscosityb y the Brookfield Test method is obtained I Model ( Rotational frequencies. min- l by multiplying this dial reading by a coafficient which depends on I the rotational frequency and characteristics of the spindle. RVF 2 4 10 20 The products to which this International Standard is applicable A RVF 100 1 10 20 50 100 are generally non-Newtonian and the measured viscosity rvR 0,5 1 2.5 5 10 20 50 100 depends on the velocity gradient to which the products are subjected during the measurement. HAF 1 2 5 10 B HAT 0.5 1 2,5 5 10 20 50 100 With these types of viscometer, the velocity gradient is not the C same for every point of the spindle. Thus, for a non-Newtonian HBF 1 2 5 10 fluid, the result is not strictly the true “viscosity at a known HBT 1 0.5 1 2.5 5 10 20 50 100 velocity gradient” and therefore is conventionally called the apparent viscosity. The shapes and sizes of the spindles are such that the viscosities corresponding to a maximum torque indication on the meter, for the various rotational frequencies, are those 3 Apparatus given in table 2. 3.1 Brookfield-type viscometer, type A, B or C, chosen The adjustment and calibration of these viscometers are usually according to the product to be tested and the desired precision. carried out by the rnanufacturer~oft he apparatus. 1) The Brookfield Test method may be carded out using test equipment eupplii by a~number of manufacturers. 1 IS 13350 (P&t ll/Sec 10) : 1999 IS0 2555 : 1989 Table 2 - Maximum value of viscosity (Pa-s)“’ as a -function of viscometer type, rotational frequency and spindle 1 Rotational Spindle number rliscometer frequency type min-1 1 2 3 4 5 6 7 100 6.1 6.4 1 2 4 10 46 zl 66,52 62 .8 25 140 286 2566 28060 h 10 1 4 10 26 46 106 466 A 5 2 8 26 46 80 200 866 4 2,5 16 25 z 100 256 loo0 2-5 4 16 46 156 400 1600 2 5 26 56 166 200 566 2ooo 1 10 46 100 260 400 1600 4oMl 6.5 26 80 266 400 800 2666 8066 166 62 6.8 2 4 8 26 80 56 6.4 1.8 4 8 16 40 166 26 1 4 10 26 46 100 466 10 2 8 26 46 86 200 806 8 5 4 16 46 86 160 466 1600 -2.5 8 32 86 166 326 800 3266 2 10 46 106 200 466 loo0 4ooo 1 26 86 200 400 866 2OCU 866Ll 65 46 166 406 800 1660 4066 16 Ooo 166 6.8 3.2 8 16 32 86 326 56 1.6 6.4 16 32 64 166 646 26 4 16 46 86 166 466 1600 10 8 32 80 166 326 860 3266 C 5 16 64 166 326 646 1600 6460 2.5 32 128 326 646 1286 3Mo 12 500 2 46 156 466 800 1600 4600 16000 1 86 326 600 1600 3206 8060 32006 65 166 646 1600 32Ml 6406 16ooO 54ooO *) 1 Pas = lb CP It is recommended that the adjustment a nd calibration be 4 Choice of rotational frequency and spindle checked from time to time by means of Newtonian liquids of known viscosity, either by the user’s laboratories or by official Choose the rotational frequency-spindle combination taking standardizing laboratories. into account the value of the viscosity to be measured, the desired precision and the velocity gradient. It is necessary to 3.2 Thermostatic liquid bath, to maintain the product make this choice in such a way that no measurement cor- being tested at the test temperature with an accuracy of responds to less than 20 % or more than 95 % of full-scale f 0.2 OC. deflection. However, for the best accuracy it is advisable to keep to the range 45 % to 95 % of full scale. Recommended test temperatures, in degrees Celsius, are: 23, 25,40,55,70,85 and 100. If a comparison of viscosities between non-Newtonian pro- ducts is desired, it is necessary to use the same rotational NOTE - If the test has to be carried at higher temperatures,i t is frequency-spindle combination for all the measurements, even advisablet o usa an extensions haft between the spindle and the if the accuracy of one of the measurements is markedly apparatus. decreased. 3.3 Additional apparatus The choice of rotational frequency automatically involves the choice of one or more typesof viscometer. +n this connection, 3.3.1 Support, which holds the viscometer and moves it in a it is recommended that, if possible, a rotational frequency of vertical plane. 10 min-1 be used. 3.3.2 Beaker, 90 mm to X2 mm in diameter and 115 mm to The rotational frequency-spindle combination to be used shall 180 mm~in height. be specified in the document that prescribes the measurement (see annex A, clause A. 1). The choice may be made in terms of 3.3.3 Thermometer, graduated in 0,l *C, to measure the the stated or expected viscosity, using table 2 and noting that temperature of the product being tested. the most suitable range is between 45 % and 95 % of full scale. 2 IS 13360 (Part ll/Sec 10) : 1999 IS0 25% 1989 5 Procedure where Mount the viscometer, with its guard stirrup, when applicable A is a coefficient depending on the type of apparatus (see sub-clause B.3.3 in annex-81 on its support. Fill the~beaker whose value is 1 for type A, 2 for type B and 8 for type C; (3.3.2) with the product to be tested, taking care not to k is a coefficient depending on the rotational frequency- introduce air bubbles, then place it in the bath (3.2) for a suffi- clent timeto reach the desired temperature. If the product con- spindle combination used; in the case of apparatus as specified in annex B, clause 8.3, the values of k are as tains volatile matter or is hygroscopic, take care to close the shown in table 3; beaker tightly during this operation. I is the mean of the two values read on the scale. With the beaker still in the bath, hold the spindle at an angle of approximately 45O to the surface of the product and immerse it in the product. Orientate the spindle vertically, and connect it Table 3 - Co&ficient k (scale 0 to 1001 for each rotational to the shaft of the apparatus. frequency-spindle combination’) Check that the spindle is vertical, using the bubble level, that l- Coefficient k for spindle number the lower end of the spindle is more than 10 mm from the lotationa bottom of the beaker and that the spindle is immersed to the requency 1 2 3 4 5 I 6 7 underside of the mark on its shaft. Immerse the thermometer I min-1 largest) ;mallen (3.3.3) in the product. 100 ! 100 1 4 la 20 40 400 Wait until the temperature of the product is between the 50 2 8 20 40 80 002 ~800 prescribed limits. Start the motor and run at the desired rota- 20 5 20 50 100 200 006 2ooo tional frequency, taking into account the manufacturer’s 10 10 40 100 2ocl 400 loo0 4000 5 20 80 200 400 800 2ooa 8CNIO recommendations. 4 25 100 250 500 loo0 2500 1oouo Allow the instrument to run and read the torque meter to the 2.5 40 160 400 800 1600 4ooo 16-000 2 50 MO 500 1000 2ooo 5ooo zoooo nearest 0.25 % of maximum value indication, in accordance 1 100 400 1000 zoo0 4ooo 1‘0 Do0 4oooo with the manufacturer’s recommendations, when a stable value 6,5 2cul 800 zoo0 4ooo 8ow 2D o00 BOCHXI has been reached on the meter. Lock the needle and stop the motor to take the reading. 1) It may be necessary to calibrate each spindle with liquids of known viscosity and to adopt slightly different values of k (see clause 8.4 in annex 8). NOTES 1 If the reading of the torque meter changes slowly, this may indicate that the product is thixotropic or rheopectic. The document that prescribes the measurement (see annex A, clause A.11 should state Express the results to three significant figures, indicating the whether the reading of the torque meter shou ld be taken after a type of viscometer (A, B or C), the number of the spindle and defined time, or as soon as it has become constant. It is also possible to the rotational frequency, as in the following example: plot the curve of viscosity as a function of period of rotation. 2 Different liquids may have different rheology. For liquids with a Brookfield viscosity (A/3/20) = 4,25 Pas thixotropic or rheopectic behaviour, the period of rotation should be * !1 Pas = 103cP). fixed, e.g. 1 min (use only 1 period since the reading of the torque meter may depend on time). Restart the motor and make another measurement. NOTE - If the measurement has been made under the conditions described in the notes to clause 5 (thixotropic or rheopectic products), ,I Continue taking measurements until two consecutive values follow the special instructions of the document mentioned in annex A. clause A. 1. are obtained that do not differ by more than 3 % from each other (unless otherwise specified in the documents mentioned in annex A, clause A. 1). Take the average of these two values. 7 Test report After each determination, detach the spindle from the The test report shall include the following particulars: apparatus and wash it thoroughly in a suitable solvent. a) a reference to this International Standard; b) the designation of the product being tested; 6 Expression of results c) the test temperature; Calculate the apparent viscosity, in Pascal seconds, of the product tested, using the formula d) the model of viscometer used; Axkxl e) the value of the apparent viscositycalculated in accord- loo0 ante with the directions of clause 6. 3 IS 13360 (Part ll/Sec 10) : 1999 IS0 2555 : 1969 Annex A (normative) General application to resins in the liquid state, emulsions and dispersions A.1 Field of application only “permitted”, than to work with different spindles. Practice shows that the results are not always the same between suc- This annex shall be used for determining the apparent viscosity cessive spindles. of resins in the liquid state, unless any indication to the contrary his given. If the value of viscosity to be measured is not known, make measurements with successive spindles, beginning with It shall be used whenever a standard or a commercial contract number 7 until the requirements of figure A.1 are met. concerning the product recommends the use of IS0 2555 and its annex A. A.2.3 Particular conditions recommended for certain products A.2 Choice of test conditions Table A.1 summarizes the particular test conditions recom- mended for a number of products in the light of international A.2.1 Rotational frequency practice. The spindle shall be chosen in accordance with the recommendations of clause 4 of this standard, taking into ac- Owing to the generally non-Newtonian behaviour of the prod- count the viscosity value. ucts covered by this annex, the results obtained with different rotational frequencies cannot theoretically be compared. Table A.1 - Recommended test conditions The choice of the frequency depends on the viscosity range to be measured. It shall be stated for each type of product. Visco- Rota- I tional Temp- Special It is necessary to establish a diagram showing the viscosity Product meter fre- frrature remarks tvw range covered for the viscometer used at the specified fre- quency quency (see figure A.1 for an example of the diagram for visco- min -l OC meters A, B and C at a frequency of 10 min - 1). Phenolic resins AlI 05 32 Polyester resins A” 10 32 Epoxy resins A” 10 32 A.2.2 Spindle Adhesives A” lOor 32 Aqueous dispersions A” 50 32 If the value of apparent viscosity to be measured is known PVC pastes A” 20 32 Read approximately, choose the spindle with the help of a diagram after (see A.2.1). showing, for each type of viscometer, the range of 1 min. viscosity covered by each spindle. 11 The use of types B or C is allowed when the viscosity of the product is greater than the viscosity limit measurable with type A at For the comparison of results, it is better to keep the same the rotational frequency recommended. spindle even if one must use it within a range where its use is 4 IS 13380 (Part ll/Sec 10) : 1999 IS0 2555 : 1989 A.3 Procedure If necessary, bubbles can be eliminated by applying a vacuum or by any other appropriate method. Follow carefully the instructions given in clause 5. Take particular care only to measure the viscosity of products In the case of products which are volatile, or have volatile con- completely free of bubbles. stituents, it is, of course, necessary to use closed vessels. Viscosity, Pa-s*’ c----------~ Recommended range c-------~ Permitted range Figure A.1 - Viscosity rang e (logarithmic scale) for every rpindle of the A, 8 and C viscometers a t a rotational frequency of 10 min - 1 I‘ 1 Pa.s = 10 CP