1、Designation: D3591 97 (Reapproved 2011)D3591 17Standard 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 oforigin
2、al 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.1. Scope Scope*1.1 This test method covers the determination of the logarithm
3、ic viscosity number of poly(vinyl chloride) (PVC) homopolymersafter compounding or processing.1.2 It is the basic assumption of this technique that the formulation of the compounded resin is known and that any additivespresent can be separated from the resin by extraction with diethyl ether. This is
4、 necessary to permit adjustment of the amount ofsample used in the test to give a resin concentration in cyclohexanone of 0.2 6 0.002 g/100 mL.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standa
5、rd to establish appropriate safety safety, health, and healthenvironmental practices and determine theapplicability of regulatory limitations prior to use. Specific precautionary statements are given in 7.3 and 8.4.1.NOTE 1This test method and ISO 1628-2 are not equivalent.1.4 This international sta
6、ndard was developed in accordance with internationally recognized principles on standardizationestablished in the Decision on Principles for the Development of International Standards, Guides and Recommendations issuedby the World Trade Organization Technical Barriers to Trade (TBT) Committee.2. Ref
7、erenced Documents2.1 ASTM Standards:2D445 Test Method for Kinematic Viscosity of Transparent and Opaque Liquids (and Calculation of Dynamic Viscosity)D446 Specifications and Operating Instructions for Glass Capillary Kinematic ViscometersD1243 Test Method for Dilute Solution Viscosity of Vinyl Chlor
8、ide PolymersD2124 Test Method for Analysis of Components in Poly(Vinyl Chloride) Compounds Using an Infrared SpectrophotometricTechniqueE1 Specification for ASTM Liquid-in-Glass ThermometersE691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test MethodE2251 Specifi
9、cation for Liquid-in-Glass ASTM Thermometers with Low-Hazard Precision LiquidsE2935 Practice for Conducting Equivalence Testing in Laboratory ApplicationsIEEE/ASTM SI-10 Standard for the Use of International System of Units (SI)2.2 ISO Standard:1628-2 PlasticsDetermination of Viscosity Number and Li
10、miting Viscosity NumberPart 2: Poly (Vinyl Chloride) Resins33. Terminology3.1 Units and symbols used in this test method are those recommended in IEEE/ASTM SI-10.3.2 Definitions of Terms Specific to This Standard:3.2.1 The term logarithmic viscosity number is defined by the equation is 9.1.1 This te
11、st method is under the jurisdiction of ASTM Committee D20 on Plastics and is the direct responsibility of Subcommittee D20.70 on Analytical Methods.Current edition approved Feb. 1, 2011Dec. 1, 2017. Published March 2011January 2018. Originally approved in 1977. Last previous edition approved in 2003
12、2011 asD3591 97(2003).(2011). DOI: 10.1520/D3591-97R11.10.1520/D3591-17.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the AS
13、TM website.3 Available from American National Standards Institute (ANSI), 25 W. 43rd St., 4th Floor, New York, NY 10036, http:/www.ansi.org.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous
14、version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.*A Summary of Changes
15、section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States14. Summary of Test Method4.1 The sample is pressed into a thin film and extracted to remove the plasticizer.4.2 The plasticizer-free film is di
16、ssolved in cyclohexanone and centrifuged to remove insoluble matter.4.3 The viscosity of the cyclohexanone solution is measured in accordance with Test Method D1243.5. Significance and Use5.1 The logarithmic viscosity number provides information on the effect of compounding or processing of PVC.5.2
17、Exposure of PVC compositions to shear or to high temperatures can result in a change in the logarithmic viscosity numberof the resin.6. Apparatus6.1 Centrifuge, capable of 2500 rpm with 100-mL sample container.6.2 Heated Hydraulic Press, capable of 620-kN ram force and a temperature of 165C.6.3 Soxh
18、let Extraction Apparatus with a 150-mL flask and a 27 by 100-mm thimble.6.4 Volumetric Flasks, 100-mL.6.5 Viscometers.46.6 Infrared Spectrophotometer, see 5.4 of Method D2124.6.7 Filter Funnel, funnel, Hirsch-Type; borosilicate glass; with coarse fritted disc, pore size: 4060 m.6.8 Thermometer, stan
19、dard, in accordance with Test Method E2251.7. Reagents7.1 Cyclohexanone, high-purity (see Annex A1).7.2 Diethyl Ether, anhydrous, reagent grade.7.3 (WarningSafety precautions should be taken to avoid personal contact, to eliminate toxic vapors, and to guard againstexplosive hazards in accordance wit
20、h the hazardous nature of the particular reagent being used.)8. Procedure8.1 Prepare the PVC sample for extraction by pressing a film. The film should be 0.02 to 0.5 mm (1 to 2 mil) thick. Preparetwo films in order to make duplicate runs.8.1.1 Heat the hydraulic press to 165C (330F).8.1.2 Place 2 g
21、of sample between two sheets of aluminum foil 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 to 620kN. Maintain the force for 3 min, then cool while maintaining the force.8.2 Weigh, to 60.2 mg, approximat
22、ely 1 g of pressed film into a 27 by 100-mm extraction thimble.8.3 Place the thimble in a Soxhlet extraction apparatus fitted with a tared 150-mLflask, and extract with 120 mLof diethyl etherfor 20 h.8.4 Remove the tared 150-mL flask containing the diethyl ether and extracted plasticizer from the ex
23、traction apparatus, andgently heat to boil off the ether.8.4.1 (WarningWhen evaporating a quantity of ether to near dryness, precautions should be taken to guard against anexplosive hazard, due to peroxides which may be in the ether or which may have been formed during use.)8.5 Place the flask in an
24、 evacuated desiccator for a minimum of 1 h to remove the last traces of ether.8.6 Weigh, to 60.2 mg, the flask containing the extracted plasticizer.8.7 Calculate the percentage plasticizer as follows:Plasticizer,%5A 3100!/B (1)where:A = weight of extracted plasticizer (7.6), andB = sample weight (7.
25、2).8.8 Dry the film to remove all solvent.4 Cannon Fenske No. 75 or Ubbelohde No. 1ASTM Ubbelohde Size 1 or Cannon-Ubbelohde No. 75 have been found satisfactory for this purpose.D3591 1728.8.1 The extracted film must be free of plasticizer. Errors in excess of 10 % will result from small residual am
26、ounts ofplasticizer. Examine the extracted film by infrared spectroscopy to ascertain that the plasticizer level is less than 0.05 % in orderto obtain satisfactory results. An example for a carbonyl containing plasticizer is shown in Fig. 1 and Fig. 2.8.9 Determine the sample size of the extracted f
27、ilm that will yield 0.02 6 0.002 g of PVC resin as follows:F 51002PR 30.2 (2)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 173where:F = weight of extracted film, g,P = plasticizer, %, andR = PVC, %.8.10 Weigh a sa
28、mple of extracted film as determined in 8.9 and transfer to a 100-mL glass-stopped volumetric flask. Take careto transfer all of the weighed sample.8.11 Add 50 to 70 mL of cyclohexanone to the flask. Make sure that all the sample is in the solvent and not attached to the neckof the flask.8.11.1 Use
29、freshly distilled cyclohexanone. Serious errors of greater than 10 % can occur by not observing this factor. Detailsof the distillation are 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
30、 not exceed 12 h and should preferably be less to minimize degradation.8.13 Cool the solution and adjust to a solution volume of 100 mL.8.14 Centrifuge for 30 min at about 2500 rpm until the solution is reasonably clear. A slight haze has been found to make nosignificant difference in the measuremen
31、ts. (As a standard for this haze level, disperse 3 mg of Dythal powder in 100 g ofcyclohexanone; this 30-ppm suspension is known to give no effect on the measurements.)8.15 Decant the supernatant liquid through a fritted-glass 4060 m filter directly into the viscometer.8.16 Place the viscometer in a
32、 water bath at a temperature of 30 6 0.5C controlled to within 60.01C. Allow at least 10 minfor the viscometer to come to equilibrium.8.17 Measure the efflux time of the solution and the pure solvent (aged at 85 6 10C) in the viscometer. The efflux time of thesolution or the solvent should be within
33、 0.1 % for repeated runs on the same filling.8.18 Duplicate determination should be run.9. Calculation9.1 Calculate the logarithmic viscosity number as follows:Logarithmic viscosity number5lnt/to!/C (3)where:ln = natural logarithm,t = efflux time of solution, s,to = efflux time of solvent, s, andC =
34、 concentration, weight of PVC sample used per 100 mL of solution, g/100 mL.9.2 The units of logarithmic viscosity number are millilitres per gram.10. Report10.1 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 Effl
35、ux time of solvent, and10.1.5 Logarithmic viscosity number.TABLE 1 Logarithmic Viscosity Number (Inherent Viscosity) ofFormulated PVC Compounds at 30CMaterial Mean Sr SRPVC1 1.0006 0.00953 0.0430PVC4 1.2425 0.01138 0.0430PVC5 1.2322 0.00584 0.0609PVC6 1.2619 0.00971 0.0411PVC7 0.9605 0.01062 0.0695O
36、verall average 0.0097 0.053Based on five laboratories, two determinations. PVC1 used four laboratories.D3591 17411. Precision and Bias11.1 Table 1 is based on a round robin,5 conducted in 1976 in accordance with Practice E691, involving five materials testedby five laboratories. For each material, a
37、ll the samples were prepared at one source, but the individual specimens were preparedat the laboratories which tested them. Each test result was the average of two individual determinations. Each laboratory obtainedtwo test results for each material.NOTE 2The explanations of r and R (11.2 11.2.3) o
38、nly are intended to present a meaningful way of considering the approximate precision of thistest method. The data in Table 1 should not be applied to acceptance or rejection of materials, as these data apply only to the materials tested in the roundrobin and are unlikely to be rigorously representa
39、tive of other lots formulations, conditions, materials, or laboratories. Users of this test method shouldapply the principles outlined in Practice E691 to generate data specific to their materials and laboratory (or between specific laboratories). The principlesof 11.2 11.2.3 then would be valid for
40、 such data.11.2 Concept of r and R in Table 1If Sr and SR have been calculated from a large enough body of data, and for test resultsthat were averages from testing two specimens for each test result, then:11.2.1 RepeatabilityTwo test results obtained within one laboratory shall be judged not equiva
41、lent if they differ by more thanthe r value for that material. The rvalue is the interval representing the critical below which the absolute difference between twoindividual test results for the same material, obtained by the same operator using the same equipment on the same day in the samelaborato
42、ry.obtained under repeatability conditions is likely to be expected to occur with a probability of approximately 0.95 (95 %).11.2.2 ReproducibilityTwo test results obtained by different laboratories shall be judged not equivalent if they differ by morethan the R value for that material. The Rvalue i
43、s the interval representing the critical below which the absolute difference betweentwo test results for the same material, obtained by different operators using different equipment in different laboratories. Only fivelaboratories participated in this round robin, making this value somewhat question
44、able.obtained under reproducibility conditionsis likely to be expected to occur with a probability of approximately 0.95 (95 %).NOTE 3Only five laboratories participated in this round robin, making this value somewhat questionable.11.2.3 Any judgment Equivalence testing on numerical data from two so
45、urces shall be conducted in accordance with11.2.1Practice E2935 or 11.2.2 would have an approximate 95 % (0.95) probability of being correct, provided that the correctnumber of laboratories had participated.any known method for judging the equivalence of two means.NOTE 4Example: A t-test.11.3 There
46、are no recognized standards by which to estimate bias of this test method.12. Keywords12.1 formulations; logarithmic viscosity number; poly(vinyl chloride); PVCANNEX(Mandatory Information)A1. DISTILLATION OF CYCLOHEXANONEA1.1 The distillation of the cyclohexanone is important, particularly if the re
47、fractive index of the solvent is above 1.4500 at 20C.To obtain the required purity, a 5 to 10-plate column is recommended. Columns in excess of 1 plate are required.A1.2 As a measure of the purity of the cyclohexanone, the solvent should have a refractive index in the range from 1.4498 to1.4499 at 2
48、0C.A1.3 It is preferable to use up the freshly distilled cyclohexanone within 1 week. The solvent should still be good for a longertime period if (1) the liquid has not taken on a yellow tint, (2) the refractive index has not increased above 1.4500, or (3) theviscosity is 1.95 mm2 /s (1.95 cSt) or l
49、ess.5 Supporting data have been filed at ASTM International Headquarters and may be obtained by requesting Research Report RR:D20-1057.D3591 175SUMMARY OF CHANGESCommittee D20 has identified the location of selected changes to this standard since the last issue(D359197(2011) that may impact the use of this standard. (December 1, 2017)(1) Section 2: Deleted E1; added references to E2251 and E2935.(2) Reworded footnote 4.(3) Added 6.7, Filter Funnel.(4) Added 6.8, Thermometer, per E2251.(5) Subsection 8.14: Deleted superscript 5.(6) Re
