1、Designation: D3591 97 (Reapproved 2011)Standard Test Method forDetermining Logarithmic Viscosity Number of Poly(VinylChloride) (PVC) in Formulated Compounds1This standard is issued under the fixed designation D3591; the number immediately following the designation indicates the year oforiginal adopt
2、ion 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.1. Scope1.1 This test method covers the determination of the loga-rithmic viscosity n
3、umber of poly(vinyl chloride) (PVC) ho-mopolymers after compounding or processing.1.2 It is the basic assumption of this technique that theformulation of the compounded resin is known and that anyadditives present can be separated from the resin by extractionwith diethyl ether. This is necessary to
4、permit adjustment of theamount of sample used in the test to give a resin concentrationin cyclohexanone of 0.2 6 0.002 g/100 mL.1.3 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
5、appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use. Specific precau-tionary statements are given in 7.3 and 8.4.1.NOTE 1This test method and ISO 1628-2 are not equivalent.2. Referenced Documents2.1 ASTM Standards:2D445 Test Method for Kin
6、ematic Viscosity of Transparentand Opaque Liquids (and Calculation of Dynamic Viscos-ity)D446 Specifications and Operating Instructions for GlassCapillary Kinematic ViscometersD1243 Test Method for Dilute Solution Viscosity of VinylChloride PolymersD2124 Test Method for Analysis of Components in Pol
7、y-(Vinyl Chloride) Compounds Using an Infrared Spectro-photometric TechniqueE1 Specification for ASTM Liquid-in-Glass ThermometersE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test MethodIEEE/ASTM SI-10 Standard for the Use of InternationalSystem of Units (SI)2
8、.2 ISO Standard:1628-2 PlasticsDetermination of Viscosity Number andLimiting Viscosity NumberPart 2: Poly (Vinyl Chlo-ride) Resins33. Terminology3.1 Units and symbols used in this test method are thoserecommended in IEEE/ASTM SI-10.3.2 Definitions of Terms Specific to This Standard:3.2.1 The term lo
9、garithmic viscosity number is defined bythe equation is 9.1.4. Summary of Test Method4.1 The sample is pressed into a thin film and extracted toremove the plasticizer.4.2 The plasticizer-free film is dissolved in cyclohexanoneand centrifuged to remove insoluble matter.4.3 The viscosity of the cycloh
10、exanone solution is measuredin accordance with Test Method D1243.5. Significance and Use5.1 The logarithmic viscosity number provides informationon the effect of compounding or processing of PVC.5.2 Exposure of PVC compositions to shear or to hightemperatures can result in a change in the logarithmi
11、c viscositynumber of the resin.6. Apparatus6.1 Centrifuge, capable of 2500 rpm with 100-mL samplecontainer.6.2 Heated Hydraulic Press, capable of 620-kN ram forceand a temperature of 165C.6.3 Soxhlet Extraction Apparatus with a 150-mL flask anda 27 by 100-mm thimble.6.4 Volumetric Flasks, 100-mL.6.5
12、 Viscometers.46.6 Infrared Spectrophotometer, see 5.4 of Method D2124.1This test method is under the jurisdiction of ASTM Committee D20 on Plasticsand is the direct responsibility of Subcommittee D20.70 on Analytical Methods.Current edition approved Feb. 1, 2011. Published March 2011. Originallyappr
13、oved in 1977. Last previous edition approved in 2003 as D3591 97(2003).DOI: 10.1520/D3591-97R11.2For 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 Docume
14、nt Summary page onthe ASTM website.3Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036, http:/www.ansi.org.4Cannon Fenske No. 75 or Ubbelohde No. 1 have been found satisfactory forthis purpose.1Copyright ASTM International, 100 Barr Harbor Drive
15、, PO Box C700, West Conshohocken, PA 19428-2959, United States.7. Reagents7.1 Cyclohexanone, high-purity (see Annex A1).7.2 Diethyl Ether, anhydrous, reagent grade.7.3 (WarningSafety precautions should be taken to avoidpersonal contact, to eliminate toxic vapors, and to guardagainst explosive hazard
16、s in accordance with the hazardousnature of the particular reagent being used.)8. Procedure8.1 Prepare the PVC sample for extraction by pressing afilm. The film should be 0.02 to 0.5 mm (1 to 2 mil) thick.Prepare two films in order to make duplicate runs.8.1.1 Heat the hydraulic press to 165C (330F)
17、.8.1.2 Place2gofsample between two sheets of aluminumfoil and insert into the press.8.1.3 Allow the sample to come to temperature for 2.5 min.During the next 0.5 min, increase the force on the sample to620 kN. Maintain the force for 3 min, then cool whilemaintaining the force.8.2 Weigh, to 60.2 mg,
18、approximately1gofpressed filminto a 27 by 100-mm extraction thimble.8.3 Place the thimble in a Soxhlet extraction apparatus fittedwith a tared 150-mL flask, and extract with 120 mL of diethylether for 20 h.8.4 Remove the tared 150-mL flask containing the diethylether and extracted plasticizer from t
19、he extraction apparatus,and gently heat to boil off the ether.8.4.1 (WarningWhen evaporating a quantity of ether tonear dryness, precautions should be taken to guard against anexplosive hazard, due to peroxides which may be in the etheror which may have been formed during use.)8.5 Place the flask in
20、 an evacuated desiccator for a mini-mumof1htoremove the last traces of ether.8.6 Weigh, to 60.2 mg, the flask containing the extractedplasticizer.8.7 Calculate the percentage plasticizer as follows:Plasticizer, % 5 A 3 100!/B (1)where:A = weight of extracted plasticizer (7.6), andB = sample weight (
21、7.2).8.8 Dry the film to remove all solvent.8.8.1 The extracted film must be free of plasticizer. Errors inexcess of 10 % will result from small residual amounts ofplasticizer. Examine the extracted film by infrared spectros-copy to ascertain that the plasticizer level is less than 0.05 % inorder to
22、 obtain satisfactory results. An example for a carbonylcontaining plasticizer is shown in Fig. 1 and Fig. 2.8.9 Determine the sample size of the extracted film that willyield 0.02 6 0.002 g of PVC resin as follows:F 5100 2 PR3 0.2 (2)where:F = weight of extracted film, g,P = plasticizer, %, andR = P
23、VC, %.8.10 Weigh a sample of extracted film as determined in 8.9and transfer to a 100-mL glass-stopped volumetric flask. Takecare to transfer all of the weighed sample.8.11 Add 50 to 70 mL of cyclohexanone to the flask. Makesure that all the sample is in the solvent and not attached to theneck of th
24、e flask.FIG. 1 Calibration Curve, 1 % Plasticizer in PVC Resin at 5.8 mFIG. 2 Acceptable Residual Plasticizer,Less than 0.05 % at 5.8 mD3591 97 (2011)28.11.1 Use freshly distilled cyclohexanone. Serious errors ofgreater than 10 % can occur by not observing this factor.Details of the distillation are
25、 discussed in Annex A1.8.12 Heat the flask to 85 6 10C until the resin is dissolved.Occasional shaking will reduce the time required for solution.Heating should not exceed 12 h and should preferably be lessto minimize degradation.8.13 Cool the solution and adjust to a solution volume of100 mL.8.14 C
26、entrifuge for 30 min at about 2500 rpm until thesolution is reasonably clear. A slight haze has been found tomake no significant difference in the measurements. (As astandard for this haze level, disperse 3 mg of Dythal5powderin 100 g of cyclohexanone; this 30-ppm suspension is knownto give no effec
27、t on the measurements.)8.15 Decant the supernatant liquid through a fritted-glassfilter directly into the viscometer.8.16 Place the viscometer in a water bath at a temperature of30 6 0.5C controlled to within 60.01C. Allow at least 10min for the viscometer to come to equilibrium.8.17 Measure the eff
28、lux time of the solution and the puresolvent (aged at 85 6 10C) in the viscometer. The efflux timeof the solution or the solvent should be within 0.1 % forrepeated runs on the same filling.8.18 Duplicate determination should be run.9. Calculation9.1 Calculate the logarithmic viscosity number as foll
29、ows:Logarithmic viscosity number 5 ln t/to!/C (3)where:ln = natural logarithm,t = efflux time of solution, s,to= efflux time of solvent, s, andC = concentration, weight of PVC sample used per 100mL of solution, g/100 mL.9.2 The units of logarithmic viscosity number are millilitresper gram.10. Report
30、10.1 Report the following information:10.1.1 Complete identification of the sample tested,10.1.2 Date,10.1.3 Efflux time of solution,10.1.4 Efflux time of solvent, and10.1.5 Logarithmic viscosity number.11. Precision and Bias11.1 Table 1 is based on a round robin5,6conducted in 1976in accordance wit
31、h Practice E691, involving five materialstested by five laboratories. For each material, all the sampleswere prepared at one source, but the individual specimens wereprepared at the laboratories which tested them. Each test resultwas the average of two individual determinations. Each labo-ratory obt
32、ained two test results for each material.NOTE 2The explanations of r and R (11.2-11.2.3) only are intended topresent a meaningful way of considering the approximate precision of thistest method. The data in Table 1 should not be applied to acceptance orrejection of materials, as these data apply onl
33、y to the materials tested inthe round robin and are unlikely to be rigorously representative of otherlots formulations, conditions, materials, or laboratories. Users of this testmethod should apply the principles outlined in Practice E691 to generatedata specific to their materials and laboratory (o
34、r between specificlaboratories). The principles of 11.2-11.2.3 then would be valid for suchdata.11.2 Concept of r and R in Table 1If Srand SRhave beencalculated from a large enough body of data, and for test resultsthat were averages from testing two specimens for each testresult, then:11.2.1 Repeat
35、abilityTwo test results obtained within onelaboratory shall be judged not equivalent if they differ by morethan the r value for that material. The r value is the intervalrepresenting the critical difference between two test results forthe same material, obtained by the same operator using thesame eq
36、uipment on the same day in the same laboratory.11.2.2 ReproducibilityTwo test results obtained by differ-ent laboratories shall be judged not equivalent if they differ bymore than the R value for that material. The R value is theinterval representing the critical difference between two testresults f
37、or the same material, obtained by different operatorsusing different equipment in different laboratories. Only fivelaboratories participated in this round robin, making this valuesomewhat questionable.11.2.3 Any judgment in accordance with 11.2.1 or 11.2.2would have an approximate 95 % (0.95) probab
38、ility of beingcorrect, provided that the correct number of laboratories hadparticipated.11.3 There are no recognized standards by which to estimatebias of this test method.12. Keywords12.1 formulations; logarithmic viscosity number; poly(vinylchloride); PVC5The sole source of supply of the Dythal po
39、wder known to the committee at thistime is National Lead Co., 111 Broadway, New York, NY 10006. If you are awareof alternative suppliers, please provide this information to ASTM InternationalHeadquarters. Your comments will receive careful consideration at a meeting of theresponsible technical commi
40、ttee1, which you may attend.6Supporting data have been filed at ASTM International Headquarters and maybe obtained by requesting Research Report RR:D20-1057.TABLE 1 Logarithmic Viscosity Number (Inherent Viscosity) ofFormulated PVC Compounds at 30CMaterial Mean SrSRPVC1 1.0006 0.00953 0.0430PVC4 1.2
41、425 0.01138 0.0430PVC5 1.2322 0.00584 0.0609PVC6 1.2619 0.00971 0.0411PVC7 0.9605 0.01062 0.0695Overall average 0.0097 0.053Based on five laboratories, two determinations. PVC1 used four laboratories.D3591 97 (2011)3ANNEX(Mandatory Information)A1. DISTILLATION OF CYCLOHEXANONEA1.1 The distillation o
42、f the cyclohexanone is important,particularly if the refractive index of the solvent is above1.4500 at 20C. To obtain the required purity,a5to10-platecolumn is recommended. Columns in excess of 1 plate arerequired.A1.2 As a measure of the purity of the cyclohexanone, thesolvent should have a refract
43、ive index in the range from 1.4498to 1.4499 at 20C.A1.3 It is preferable to use up the freshly distilled cyclo-hexanone within 1 week. The solvent should still be good fora longer time period if (1) the liquid has not taken on a yellowtint, (2) the refractive index has not increased above 1.4500, or
44、(3) the viscosity is 1.95 mm2/s (1.95 cSt) or less.ASTM 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 validity of any such patent righ
45、ts, 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 comments are invited either for
46、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 not received a fair hearing
47、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). Permission rights to photocopy the standard may also be secured from the ASTM website (www.astm.org/COPYRIGHT/).D3591 97 (2011)4
