1、Designation: D1343 95 (Reapproved 2011)Standard Test Method forViscosity of Cellulose Derivatives by Ball-Drop Method1This standard is issued under the fixed designation D1343; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the ye
2、ar of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.1. Scope1.1 This test method describes the
3、apparatus and generalprocedure for making ball-drop viscosity measurements onsolutions of various cellulose derivatives. Instructions forsample preparation, solution concentration, and other detailsare discussed in theASTM methods for the respective cellulosederivatives.1.2 This test method is appli
4、cable to solutions of variouscellulose derivatives having viscosities greater than 10 P, byusing balls of various diameters and densities. Viscosity resultsare expressed preferably in poises.1.3 In commercial practice, viscosities are often expressedin seconds using 2.38-mm (332-in.) stainless steel
5、 balls.2Whenthe viscosity is outside the practical range for these balls (75 to300 P), the measurement can be made using a calibrated pipetviscometer or a different ball and calculating the observedviscosity to the corresponding time for a 2.38-mm (332-in.)ball, even though it is a small fraction of
6、 a second.1.4 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are for informationonly.1.5 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to est
7、ablish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:3D301 Test Methods for Soluble Cellulose Nitrate4D445 Test Method for Kinematic Viscosity of Transparentand Opaque Liquids (and Calculatio
8、n of Dynamic Viscos-ity)D817 Test Methods of Testing Cellulose Acetate Propionateand Cellulose Acetate ButyrateD871 Test Methods of Testing Cellulose AcetateE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method3. Summary of Test Method3.1 A solution of the
9、cellulose derivative is made in asuitable solvent and allowed to equilibrate at a chosen tem-perature. A stainless steel or aluminum ball is dropped into thesolution, and the time required for it to cover a measureddistance in its fall is recorded. The viscosity of the solution canthen be calculated
10、 in poise or recorded in seconds.NOTE 1The choice of solvent has significant influence on viscosity.4. Significance and Use4.1 This test provides an easy method of determining theviscosity of cellulose derivatives in a given solvent. Theanswers are in units commonly used in industrial practice.Such
11、information is needed for cellulose derivatives that are tobe extruded, molded, sprayed, or brushed as is or in solution.5. Apparatus5.1 Constant-Temperature Water Bath, glass-walled.1This test method is under the jurisdiction of ASTM Committee D01 on Paintand Related Coatings, Materials, and Applic
12、ations and is the direct responsibility ofSubcommittee D01.36 on Cellulose and Cellulose Derivatives.Current edition approved June 1, 2011. Published June 2011. Originallyapproved in 1954. Last previous edition approved in 2006 as D1343 95 (2006).DOI: 10.1520/D1343-95R11.2When a332-in. stainless ste
13、el ball is used, the viscosities in seconds should bepractically the same as those obtained using the apparatus described in Section 11of Test Methods D871 48, and in Section 10 of Test Methods D301 50, whichlast appeared in the 1952 Annual Book of ASTM Standards, Part 4.3For referenced ASTM standar
14、ds, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.4Withdrawn. The last approved version of this historical standard is referencedon www.ast
15、m.org.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.5.1.1 For routine testing, an aquarium viscometer is recom-mended. This viscometer is a rectangular glass enclosure withfront and rear walls that have etched horizontal parallel l
16、ines50.8 mm (2.00 6 0.02 in.) apart. The bottles containing thesamples solutions are set inside the viscometer at a level suchthat the upper etched line of the viscometer is at least 12.7 mm(12 in.) below the upper surface of the solution in the bottle,and the lower etched line of the viscometer is
17、at least 12.7 mm(12 in.) above the bottom of the sample bottle. Suitable lightingis provided to enable the observer to sight across the paralleletched lines, through the sample bottle and solution, avoidingin this manner parallax errors. With this viscometer no timingmarkers need to be provided on t
18、he bottles.5.2 Bottles and Caps:5.2.1 Bottles, round or square, conforming to the dimen-sional requirements shown in Table 1, shall be used. Screwcaps of metal or phenolic plastic in sizes to fit the bottles andhaving aluminum foil or cardboard and cellophane liners maybe used to close the bottles.
19、Alternatively, rubber stopperscovered with aluminum or tin foil, may also be used asclosures. In this latter case, solvent loss during measurement ofviscosity can be minimized by removing the stopper, leavingthe foil in place, and making a small hole in the center of thefoil through which the balls
20、may be dropped.5.2.2 Timing marks shall be provided around each bottle oron the front and back of the glass-walled constant-temperaturewater bath, to avoid parallax errors. The lower timing markshall be at least 13 mm (0.5 in.) above the base of the bottle,and the upper mark shall be 50.8 6 0.5 mm (
21、2.00 6 0.02 in.)above the lower mark.Apractical means of marking consists ofwrapping a 50.8-mm (2-in.) strip of transparent sheetingaround the water bath at the proper location. The edges of thesheeting may be darkened with crayon. A light located back ofthe water bath aids in observing the ball dur
22、ing its fall.5.3 BallsUnless specifically directed otherwise, balls ofvarying size and density shall be used, depending on theviscosity of the solution. Table 2 gives the useful ranges,approximate apparatus constants, and dimensions of severalsuch balls. The exact diameter, weight, and density shall
23、 bedetermined accurately for each lot of balls used.5.4 Stop WatchA stop watch reading to 0.2 s.6. Calibration6.1 Calculate the apparatus constant, K, using the followingequation and exact dimensions of the bottle and balls used:K 5 2gr21 2 2.104d/D! 1 2.09d/D!3#/9Lwhere:g = acceleration of gravity
24、in cgs unitsr = ball radius, cm,d = ball diameter, cm,D = bottle diameter, cm (in the case of square bottles theaverage of the side to side and corner to cornerdiameters shall be used), andL = distance of ball drop, cm.7. Procedure7.1 Preparation of SolutionDry the sample and prepare asolution as sp
25、ecified for the particular material. Such instruc-tions are given in the viscosity sections of Test Methods D301,D871, and D817. Weigh into the bottle an appropriate amountof dry sample and specified solvent, accurate to 0.1 g, to makeabout 350 mL of solution. The accurate and precise make up ofthe
26、solution is a necessity (example: 60.00 g of celluloseacetate and 240.00 g solvent). Close the bottle tightly. Allow tostand a short time for the solvent to penetrate the sample. Thentumble or shake until a uniform solution is obtained. For somesamples this may require several days. Transfer to the
27、waterbath at 25 6 0.1C, and allow the solution to come totemperature. A practical method to determine possible solventloss during this time involves weighing the bottle immediatelyafter adding the components, and again before performing theball drop.7.2 Viscosity DeterminationDrop a 2.38-mm (332-in.
28、)stainless steel ball through the center of the column of solutionand time its fall through the marked 50.8-mm (2-in.) distance,using a stop watch and taking precautions to avoid parallaxerrors. If the observed time is less than 15 s or greater than100 s repeat the measurement, unless directed other
29、wise, usinga different ball (see Table 2) which has a time of fall withinthese limits. If the solution is known to be thixotropic in natureor if the times of fall for successive balls vary significantly, usefreshly prepared solutions for duplicate measurements ormeasurements with balls of other size
30、s.7.3 Determination of Lower Viscosities If the viscosity ofthe solution is too low to measure satisfactorily using one ofTABLE 1 BottlesBottle Round SquareCapacity, oz 16 16Weight, oz 12 12Height, in. 6.7 7Inside diameter, cm 6.4Side to side, cm . 6.0Corner to corner, cm . 7.2TABLE 2 BallsBallVisco
31、sity Range,PTypical DataApparatusConstant, KDiameter, cm Weight, g Density, g/cm3, a1.59-mm (116-in.) (aluminum) 10 to 50 0.256 0.1588 0.00591 2.821.59-mm (116-in.) (stainless steel) 35 to 150 0.256 0.1588 0.01605 7.662.38-mm (332-in.) 75 to 300 0.560 0.2380 0.0542 7.683.18-mm (18-in.) 125 to 600 0.
32、965 0.3170 0.1277 7.685.56-mm (732-in.) 350 to 1800 2.70 0.5556 0.6897 7.68D1343 95 (2011)2the balls, use a calibrated pipet as described in Test MethodD445, or other instrument of suitable range. Calculate theresult in poises. Convert poises to equivalent ball-drop secondsas shown in 8.2.8. Calcula
33、tion8.1 Ball-Drop ViscositiesCalculate the viscosity in poisesas follows:h5Ka 2 b!twhere:h = viscosity at the specified temperature, P,K = apparatus constant,4a = ball density4, in g/cm33,b = solution density, given in referenced documents TestMethods D817 and D871, g/cm3, andt = time of fall, s.In
34、the case of a ball of stated diameter and density, thiscalculation can be simplified to:5h5F 3 t,where:F = K(a b).This factor varies with solution density, b.Approximate factorsfor the various balls can be read from Fig. 1. Exact factors canbe calculated from the exact measurements of the viscometer
35、and balls.8.2 Poises to SecondsPoises may be converted to equiva-lent ball-drop seconds, t, as follows:t for 3/322in. ball! 5h/Ka 2 b!where:h = observed viscosity, P,K = apparatus constant for the332 in. stainless steel ball,a = ball density for the332-in. stainless steel ball, andb = solution densi
36、ty for the solution being tested.9. Report9.1 Results shall be reported in poises, or in seconds, for a332-in. stainless steel ball.10. Precision and Bias10.1 PrecisionTable 3 is based on a round robin con-ducted in 1991 in accordance with Practice E691, involvingtwo materials (cellulose acetate and
37、 cellulose acetate butyrate),tested by eight laboratories.6Both materials were prepared atone source, which also provided the sample bottles and thestainless steel balls. Each test result was the average of fourball drops on one prepared dope. Each laboratory obtainedthree test results (one test res
38、ult was obtained each week).NOTE 2The following explanations of r and R (10.2 through 10.2.3)are only intended to present a meaningful way of considering theapproximate precision of this test method. The data in Table 3 should notbe rigorously applied to acceptance or rejection of material, as those
39、 dataare specific to the round robin and may not be representative of other lots,conditions, materials, or laboratories. Users of this test method shouldapply the principles outlined in Practice E691 to generate data specific totheir laboratory and materials, or between specific laboratories. Thepri
40、nciples of 10.2 through 10.2.3, would then be valid for such data.10.2 Concept of Repeatability/ReproducbilityIf repeat-ability standard deviation (Sr) and reproducibility standarddeviation (SR) have been calculated from a large enough bodyof data, and for test results that are averages of four ball
41、 dropsper dope, the information in 10.2.1 through 10.2.3 applies.10.2.1 Repeatability (r) is used for comparing two testresults for the same material by the same operator using thesame equipment. The two test results should be judged notequivalent if they differ by more than the r value for thatmate
42、rial.10.2.2 Reproducibility (R) is used for comparing two testresults for the same material, obtained by different operators5See Table 2 for approximate values.6Supporting data have been filed at ASTM International Headquarters and maybe obtained by requesting Research Report RR:D01-1074.TABLE 3 Pre
43、cision Statistics from Round Robin Study According to Practice E691Material AverageLaboratoryStandardDeviationRepeatabilityStandardDeviationReproducibilityStandardDeviationRepeatability ReproducibilityCAB-381-20 20.35 0.823 0.458 0.942 1.28 2.64CA-394-60 57.13 2.661 1.755 3.187 4.91 8.92FIG. 1 Facto
44、rs for Converting Viscosities in Seconds to Poisesh =F3 tD1343 95 (2011)3using different equipment. The two test results should bejudged not equivalent if they differ by more than the R valuefor that material.10.2.3 Any judgement in accordance with 10.2.1 or 10.2.2would have an approximate 95 % (0.9
45、5) probability of beingcorrect.10.3 BiasThere are no recognized standards by which toestimate bias of this test method.11. Keywords11.1 ball drop; cellulose esters; viscosityASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mention
46、edin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and
47、 must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of
48、 theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box
49、C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org). Permission rights to photocopy the standard may also be secured from the ASTM website (www.astm.org/COPYRIGHT/).D1343 95 (2011)4
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