1、Designation: D 1343 95 (Reapproved 2006)Standard Test Method forViscosity of Cellulose Derivatives by Ball-Drop Method1This standard is issued under the fixed designation D 1343; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the
2、year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) 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 t
3、he 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 ap
4、plicable 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 2.38mm (332-in.) stainless ste
5、el 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
6、of 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 e
7、stablish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:3D 301 Test Methods for Soluble Cellulose NitrateD 445 Test Method for Kinematic Viscosity of Transparentand Opaque Liquids (and the Cal
8、culation of DynamicViscosity)D 817 Test Methods of Testing Cellulose Acetate Propi-onate and Cellulose Acetate ButyrateD 871 Test Methods of Testing Cellulose AcetateE 691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method3. Summary of Test Method3.1 A soluti
9、on of the 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
10、calculated 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 prac
11、tice.Such 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.5.1.1 For routine testing, an aquarium viscometer is recom-mended. This viscometer is a rectangular glass e
12、nclosure withfront and rear walls that have etched horizontal parallel lines50.8 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 th
13、e solution in the bottle,and the lower etched line of the viscometer is 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 paralla
14、x errors. With this viscometer no timingmarkers need to be provided on the bottles.5.2 Bottles and Caps:1This test method is under the jurisdiction of ASTM Committee D01 on Paintand Related Coatings, Materials, and Applications and is the direct responsibility ofSubcommittee D01.36 on Cellulose and
15、Cellulose Derivatives.Current edition approved April 1, 2006. Published April 2006. Originallyapproved in 1954. Last previous edition approved in 2000 as D 1343 95 (2000).2When a332-in. stainless steel ball is used, the viscosities in seconds should bepractically the same as those obtained using the
16、 apparatus described in Section 11of Test Methods D 871 48, and in Section 10 of Test Methods D 301 50, whichlast appeared in the 1952 Annual Book of ASTM Standards, Part 4.3For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For A
17、nnual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.5.2.1 Bottles, round or square, conforming to the dimen-sional requiremen
18、ts 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. Alternatively, rubber stopperscovered with aluminum or tin foil, may also be used asclosures. In this lat
19、ter 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 may be dropped.5.2.2 Timing marks shall be provided around each bottle oron the front and back of the gla
20、ss-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 (2.00 6 0.02 in.)above the lower mark.Apractical means of marking consists ofwrapping a 50.8 mm (2-in.) st
21、rip of transparent sheeting aroundthe water bath at the proper location. The edges of the sheetingmay be darkened with crayon.Alight located back of the waterbath aids in observing the ball during its fall.5.3 BallsUnless specifically directed otherwise, balls ofvarying size and density shall be use
22、d, 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 bedetermined accurately for each lot of balls used.5.4 Stop WatchA stop watch reading to 0.2 s.6. Calibrat
23、ion6.1 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 in cgs unitsr = ball radius, cm,d = ball diameter, cm,D = bottle diameter, cm (in the case of square bottle
24、s 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 specified for the particular material. Such instruc-tions are given in the viscosity sections of Test Methods
25、 D 301,D 871, and D 817. 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 solution is a necessity (example: 60.00 g of celluloseacetate and 240.00 g solvent). Close the bottle ti
26、ghtly. 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 waterbath at 25 6 0.1C, and allow the solution to come totemperature. A practical method to determine po
27、ssible 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.)stainless steel ball through the center of the column of solutionand time its fall through the marked 5
28、0.8-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 otherwise, usinga different ball (see Table 2) which has a time of fall withinthese limits. If the solution i
29、s 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 sizes.7.3 Determination of Lower Viscosities If the viscosity ofthe solution is too low to measure satisfact
30、orily using one ofthe balls, use a calibrated pipet as described in Test MethodD 445, or other instrument of suitable range. Calculate theresult in poises. Convert poises to equivalent ball-drop secondsas shown in 8.2.8. Calculation8.1 Ball-Drop ViscositiesCalculate the viscosity in poisesas follows
31、: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 D 817 and D 871, g/cm3, andt = time of fall, s.In the case of a ball of stated diameter and density, thiscalculation can
32、 be simplified to:4h5F 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 viscometerand balls.8.2 Poises to SecondsPoises may be converted to equiva-lent
33、ball-drop seconds, t, as follows:4See Table 2 for approximate values.TABLE 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 . 7.2D 1343 95 (2006)2t for 3/322in. ball! 5h/Ka 2 b!where:h = observed viscosit
34、y, P,K = apparatus constant for the332 in. stainless steel ball,a = ball density for the332-in. stainless steel ball, andb = solution density 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 Pr
35、ecisionTable 3 is based on a round robin con-ducted in 1991 in accordance with Practice E 691, involvingtwo materials (cellulose acetate and cellulose acetate butyrate),tested by eight laboratories.5Both materials were prepared atone source, which also provided the sample bottles and thestainless st
36、eel balls. Each test result was the average of fourball drops on one prepared dope. Each laboratory obtainedthree test results (one test result 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 theapp
37、roximate precision of this test method. The data in Table 3 should notbe rigorously applied to acceptance or rejection of material, as those dataare specific to the round robin and may not be representative of other lots,conditions, materials, or laboratories. Users of this test method shouldapply t
38、he principles outlined in Practice E 691 to generate data specific totheir laboratory and materials, or between specific laboratories. Theprinciples 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 rep
39、roducibility standarddeviation (SR) have been calculated from a large enough bodyof data, and for test results that are averages of four ball 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
40、same operator using thesame equipment. The two test results should be judged notequivalent if they differ by more than the r value for thatmaterial.10.2.2 Reproducibility, (R) is used for comparing two testresults for the same material, obtained by different operatorsusing different equipment. The t
41、wo 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 % (0.95) probability of beingcorrect.10.3 BiasThere are no recognized standards by which toestimate bias of thi
42、s test method.11. Keywords11.1 ball drop; cellulose esters; viscosity5Supporting data have been filed at ASTM International Headquarters and maybe obtained by requesting Research Report RR:D01-1074.TABLE 2 BallsBallViscosity Range,PTypical DataApparatusConstant, KDiameter, cm Weight, g Density, g/cm
43、3, 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 0.965 0.3170 0.1277 7.685.56-mm (732-in.) 350 to 1800 2.70 0.5556 0.6897 7.68TABLE
44、 3 Precision 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
45、 Factors for Converting Viscosities in Seconds to Poisesh =F3 tD 1343 95 (2006)3ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the val
46、idity 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 must be reviewed every five years andif not revised, either reapproved or withdrawn. Your com
47、ments 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 theresponsible technical committee, which you may attend. If you feel that your comments have
48、 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 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).D 1343 95 (2006)4
