1、Designation: D 3591 97 (Reapproved 2003)Standard Test Method forDetermining Logarithmic Viscosity Number of Poly(VinylChloride) (PVC) in Formulated Compounds1This standard is issued under the fixed designation D 3591; the number immediately following the designation indicates the year oforiginal ado
2、ption or, in the case of revision, the 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.1. Scope*1.1 This test method covers the determination of the loga-rithmic viscosi
3、ty number 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
4、 to 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 establ
5、ish 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:D 445 Test Method for
6、 Kinematic Viscosity of Transparentand Opaque Liquids (the Calculation of Dynamic Viscos-ity)2D 446 Specification and Operating Instructions for GlassCapillary Kinematic Viscometers2D 1243 Test Method for Dilute Solution Viscosity of VinylChloride Polymers3D 2124 Method for Analysis of Components in
7、 Poly(VinylChloride) Compounds Using an Infrared Spectrophoto-metric Technique3E 1 Specification for ASTM Thermometers4E 691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method5IEEE/ASTM SI 10 Standard for the Use of InternationalSystem of Units (SI)52.2 ISO S
8、tandard:1628-2 PlasticsDetermination of Viscosity Number andLimiting Viscosity NumberPart 2: Poly (Vinyl Chlo-ride) Resins63. Terminology3.1 Units and symbols used in this test method are thoserecommended in Standard IEEE/ASTM SI 10.3.2 Definitions of Terms Specific to This Standard:3.2.1 The term l
9、ogarithmic 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 cyclo
10、hexanone solution is measuredin accordance with Test Method D 1243.5. 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 logarith
11、mic 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
12、.5 Viscometers.76.6 Infrared Spectrophotometer, see 5.4 of Method D 2124.1This 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 March 10, 2003. Published April 2003. Originall
13、yapproved in 1977. Last previous edition approved in 1997 as D 3591 97.2Annual Book of ASTM Standards, Vol 05.01.3Annual Book of ASTM Standards, Vol 08.01.4Annual Book of ASTM Standards, Vol 14.03.5Annual Book of ASTM Standards, Vol 14.02.6Available from American National Standards Institute, 25 W.
14、43rd St., 4thFloor, New York, NY 10036.7Cannon Fenske No. 75 or Ubbelohde No. 1 have been found satisfactory forthis purpose.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United S
15、tates.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 hazards in accordance with the hazardousnature of the particula
16、r 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).8.1.2 Place2gofsample between two sheets of aluminumfoil
17、 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, approximately1gofpressed filminto a 27 by 100-mm extracti
18、on 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 the extraction apparatus,and gently heat to boil off the e
19、ther.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 an evacuated desiccator for a mini-mumof1htoremove the l
20、ast 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 (7.2).8.8 Dry the film to remove all solvent.8.8.1 The ext
21、racted 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 obtain satisfactory results. An example for a carbonylco
22、ntaining 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 = PVC, %.8.10 Weigh a sample of extracted film as determined
23、 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 the flask.FIG. 1 Calibration Curve, 1 % Plasticizer in PVC
24、Resin at 5.8 mFIG. 2 Acceptable Residual Plasticizer,Less than 0.05 % at 5.8 mD 3591 97 (2003)28.11.1 Use freshly distilled cyclohexanone. Serious errors ofgreater than 10 % can occur by not observing this factor.Details of the distillation are discussed in Annex A1.8.12 Heat the flask to 85 6 10C u
25、ntil 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 Centrifuge for 30 min at about 2500 rpm until thesolution
26、 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 Dythal8powderin 100 g of cyclohexanone; this 30-ppm suspension is knownto give no effect on the measurements.)8.15 Decant the supernatant liqui
27、d 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 efflux time of the solution and the puresolvent (aged at 85
28、 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 follows:Logarithmic viscosity number 5 ln t/to!/C (3)where:l
29、n = 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. Report10.1 Report the following information:10.1.1 Complete id
30、entification 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 robin8,9conducted in 1976in accordance with Practice E 691, involving five materialstested by five
31、 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 obtained two test results for each material.NOTE 2The expl
32、anations 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 only to the materials tested inthe round robin and are unl
33、ikely to be rigorously representative of otherlots formulations, conditions, materials, or laboratories. Users of this testmethod should apply the principles outlined in Practice E 691 to generatedata specific to their materials and laboratory (or between specificlaboratories). The principles of 11.
34、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 RepeatabilityTwo test results obtained within onelaboratory
35、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 equipment on the same day in the same laboratory.11.2.2
36、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 for the same material, obtained by different operatorsu
37、sing 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) probability of beingcorrect, provided that the correct numbe
38、r 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); PVC8The sole source of supply of the Dythal powder known to the committee at thistime is National Le
39、ad 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 committee1, which you may attend.9Supporting data have been
40、 filed at ASTM International Headquarters and maybe obtained by requesting Research Report RR: D201057.TABLE 1 Logarithmic Viscosity Number (Inherent Viscosity) ofFormulated PVC Compounds at 30CMaterial Mean SrSRPVC1 1.0006 0.00953 0.0430PVC4 1.2425 0.01138 0.0430PVC5 1.2322 0.00584 0.0609PVC6 1.261
41、9 0.00971 0.0411PVC7 0.9605 0.01062 0.0695Overall average 0.0097 0.053Based on five laboratories, two determinations. PVC1 used four laboratories.D 3591 97 (2003)3ANNEX(Mandatory Information)A1. DISTILLATION OF CYCLOHEXANONEA1.1 The distillation of the cyclohexanone is important,particularly if the
42、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 refractive index in the range from 1.4498to 1.4499 at 20C.A1
43、.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(3) the viscosity is 1.95 mm2/s (1.95 cSt) or less.SU
44、MMARY OF CHANGESCommittee D20 has identified the location of selected changes to this standard since the last issue(D 3591 97) that may impact the use of this standard.(1) Revisions to this edition include changes to Sections 2 and11, as well as the addition of Table 1 and Note 1.ASTM International
45、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 rights, and the riskof infringement of such rights, are entirely their own
46、 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 revision of this standard or for additional standardsand should be add
47、ressed 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 you shouldmake your views known to the ASTM Committee on Standards, at
48、 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 3591 97 (2003)4
