ASTM_D_1343_-_95_2011.pdf

Designation:D134395(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 year 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 U.S.Department of Defense.1.Scope1.1 This test method describes the 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 applicable 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 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 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 establish 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 Nitrate(With-drawn 2011)4D445 Test Method for Kinematic Viscosity of Transparentand Opaque Liquids(and Calculation 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 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 in poise or recorded in seconds.NOTE1The 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 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 enclosure withfront and rear walls that have etched horizontal parallel lines50.8 mm(2.00 6 0.02 in.)apart.The bottles containing the1This 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 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 steel 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 standards,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.4The last approved version of this historical standard is referenced onwww.astm.org.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 samples solutions are set inside the viscometer at a level suchthat the upper etched line of the viscometer is at least 12.7 mm(12in.)below the upper surface of the solution in the bottle,and the lower etched line of the viscometer is at least 12.7 mm(12in.)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 timin