1、Designation: D4350 13D4350 15Standard Test Method forCorrosivity Index of Plastics and Fillers1This standard is issued under the fixed designation D4350; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A
2、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. Scope*1.1 This test method is designed for use in obtainin
3、g the specific conductance of a water extract of plastics and fillers. Themagnitude of this conductance may be taken as conductance, called the corrosivity index, is an index of the likelihood that, in ahumid atmosphere, metal surfaces in contact with these materials may becomecan be corroded due to
4、 galvanic action or directchemical attack; this is called the corrosivity index. attack.NOTE 1There is no known ISO equivalent to this standard.1.2 The values stated in SI units are to be regarded as standard.1.3 This standard does not purport to address all of the safety concerns, if any, associate
5、d with its use. It is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use. Specific precautionary statements are given in Section 7.2. Referenced Documents2.1 ASTM Standards:2D618 Pr
6、actice for Conditioning Plastics for TestingD883 Terminology Relating to PlasticsD1193 Specification for Reagent WaterE1 Specification for ASTM Liquid-in-Glass ThermometersE11 Specification for Woven Wire Test Sieve Cloth and Test SievesE145 Specification for Gravity-Convection and Forced-Ventilatio
7、n OvensE691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test MethodE2251 Specification for Liquid-in-Glass ASTM Thermometers with Low-Hazard Precision Liquids3. Summary of Test Method3.1 Specimens of plastics or fillers are immersed in distilled water and exposed
8、 to specified conditions of temperature and time.The specific resistance of each of the solutions extracted from the test specimens is measured by using the specified conductivitycell. The specific conductance is calculated from the data and is called the corrosivity index of the material.3. Termino
9、logy3.1 Definitions of TermsFor definitions of terms used in this test method associated with plastics issues refer to theterminology contained in Terminology D883.4. Significance and Use4.1 This test method provides a means for comparing the corrosive potential of plastics and fillers in humid atmo
10、spheres.4.2 This test method is intended for use in research and evaluation.1 This test method is under the jurisdiction of ASTM Committee D20 on Plastics and is the direct responsibility of Subcommittee D20.16 on Thermosetting Materials.Current edition approved Dec. 15, 2013June 1, 2015. Published
11、December 2013June 2015. Originally approved in 1984. Last previous edition approved in 20052013 asD4350 - 00 (2005).D4350 - 13. DOI: 10.1520/D4350-13.10.1520/D4350-15.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual B
12、ook of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.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 version. Becauseit may not be tech
13、nically 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 section appears at the end of this
14、 standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States15. Apparatus5.1 Conductance Bridge, Wheatstone type, with a range from 1 to 250 000- measured resistance, a built-in potentiometer, a1000 6 50-cycles per second oscillator, and
15、a sensitive null point indicator. The bridge shall be capable of measuring resistancewith an accuracy of 62 %.5.2 Conductivity Cell, dip-type, micro, for solutions of medium conductance. The cell should needs to have a cell constant ofapproximately 1.0 cm1. The borosilicate glass shall have a maximu
16、m outside tube diameter of 12.7 mm, overall length of 177.8mm, chamber inside diameter of 9.5 mm, and chamber depth of 50.8 mm.35.3 Drill, electric, capable of holding a 10.54-mm drill bit, and rotating at 500-r/min maximum speed.5.4 Mill, such as laboratory Wiley cutting mill or equivalent.5.5 Siev
17、es, standard (alternative) sieve designations 425 m (No. 40), and 250 m (No. 60) in accordance with SpecificationE11.5.6 Analytical Balance, capable of determining mass to the nearest 1.0 mg.5.7 Oven, forced-ventilation type, with uniformity of temperature within 61 % of the differential between ove
18、n and ambienttemperature, with a rate of ventilation of 100 to 200 air changes per hour, in accordance with Specification E145, Type IIA.5.8 Thermometer, solid-stem, precision, ASTM No. 63C, in accordance with Specification E1. Temperature measuring deviceswith equivalent accuracy and characteristic
19、s, such as RTDs and thermistors, may be used. In addition,are permitted. Additionally,use of ASTM No. S63C in accordance with Specification E2251E2251 may be used.is acceptable.5.9 Chemical Glassware:5.9.1 Borosilicate Glass Flask, nominally 1000-mL size, with ground glass stopper.5.9.2 Borosilicate
20、 Glass Erlenmeyer Flask, 65-mL actual capacity to bottom of stopper (nominally 50-mL size), with groundglass stopper No. 19.5.9.3 Pipet, volumetric, 50-mL capacity, calibrated “to deliver.”6. Reagents and Materials6.1 Distilled Water, Type III, reagent water as defined in Specification D1193. When s
21、tored in borosilicate glass bottles at 236 2C, the water shall have a calculated specific conductance of less than 2.0 106, ohm1, cm1.6.2 Potassium Chloride Solution, consisting of 0.7453 g of reagent grade potassium chloride, previously dried at 105 6 3Cfor at least 24 h, dissolved in 1000 g of dis
22、tilled water. The solution shall be stored in a borosilicate glass stoppered bottle. Thespecific conductance of this 0.0100 Demal KCl solution is 0.0007736 ohm1, cm1 at 0C, 0.0012205 ohm1, cm1 at 18C, and0.0014087 ohm1, cm1 at 25C.4 This specific conductance versus temperature is plotted in Fig. 1.6
23、.3 Grease, silicone, not soluble in water nor containing any water-soluble constituents. In the control specimens, water exposedto the grease on the stopper shall have a specific conductance less than 7 106, ohm1, cm1.7. Safety Hazards7.1 Some plastics and fillers are known to contain toxic componen
24、ts and special precautions are required in handling. Themanufacturers Diligently follow the manufacturers precautionary instructions and sound laboratory safety practices should bediligently followed.practices.8. Sampling8.1 Because of the diverse nature of plastics and fillers, and the various form
25、s and packages commercially available, no standardmethods of sampling have been established. An adequate amount of material, representative of each ingredient, shall be selectedfrom each lot to permit preparation of specimens as agreed upon between the buyer and the seller.9. Specimen Preparation9.1
26、 Plastics, either prepared in accordance with the manufacturersmanufacturers directions, or as received from themanufacturer, shall be drilled with a sharp drill at a rate not exceeding 27.5 mm/s (10.54-mm diameter drill at 500 r/min), and thedrillings shall be ground in a mill. Care shall be exerci
27、sed so as not to overheat the material when drilling or grinding, asoverheating shall cause changes in the characteristics of the material. That fraction of ground plastics that passes a 425-m sieve,but is retained by a 250-m sieve, is used for the test.3 The sole source of supply of the conductivit
28、y cell (Model No. 3403) known to the committee at this time is Yellow Springs Instrument Co., Inc., P.O. Box 279, YellowSprings, OH 45387. If you are aware of alternative suppliers, please provide this information to ASTM International Headquarters. Your comments will receive carefulconsideration at
29、 a meeting of the responsible technical committee,1 which you may attend.4 Specific conductance values are based on the work of Jones, G., and Bradshaw, B. C., J. Amer. Chem. Soc., 55 (1933) 1780. For more detailed information on the useof Demal KCl, see“ Electrolyte Solutions,” by Robinson, R. A.,
30、and Stokes, R. H., Academic Press, Inc., New York, 1955, pp. 9496.D4350 1529.2 Fillers, shall be used as received from the manufacturer.10. Conditioning10.1 Unless otherwise specified, condition all specimens for a minimum of 40 h at the standard laboratory atmosphere (23 62C, 50 6 10 % relative hum
31、idity), in accordance with Procedure A of Practice D618.11. Number of Test Specimens11.1 At least three specimens shall be tested for each material.12. Procedure12.1 Place 0.50 6 0.01 g of the test material in each of three Erlenmeyer flasks. Prepare at least three flasks, without material,as contro
32、ls for the water and grease.12.2 Add 50.0 mL of distilled water with a pipet to each flask.12.3 Grease the flask stopper with silicone grease and stopper flasks tightly. Agitate the flasks until the specimen particles arethoroughly wetted.FIG. 1 Specific Conductance of 0.0100 Demal KClD4350 15312.4
33、Place the stoppered flasks in an oven at 71 6 3C for a total of 288 h (12 days).At the end of the first day of oven storage,examine the flasks to determine that no stoppers have become loose or blown off, with consequent loss of liquid (in which eventthe specimen shall be discarded). Agitate the fla
34、sks in order to break up large aggregates of the test specimen and to dislodge airbubbles that tend to float particles of the test specimen, thus preventing proper wetting.12.5 At the end of 288 6 2 h, remove the stoppered flasks from the oven and allow them to cool to 23 6 2C. Again agitatethe flas
35、ks thoroughly and allow the solids to settle.12.6 Determine the cell constant of the conductivity cell.12.6.1 Pipet 50.0 mL of 0.0100 Demal KCl into each of three Erlenmeyer flasks, and allow to come to 23 6 2C.12.6.2 Use a thermometer to determine the temperature to the nearest 0.1C of the liquid i
36、n the flask immediately prior to thetime of specific resistance measurements.12.6.3 Dip the conductivity cell vertically into the liquid until the bottom edge of the cell rests on the bottom of the flask.12.6.4 Measure the specific resistance in ohms of each of the solutions with a conductance bridg
37、e at 1000 6 50 cycles persecond.12.7 Determine the specific resistance of the specimens and controls. Use the same technique and the same conductivity cellused in 12.6.3 and 12.6.4. Measurements shall be made at the same temperature determined in 12.6.2. Measurements shall be madewithin 4 h after re
38、moval from oven.13. Calculation13.1 Calculate the cell constant. The conductivity cell constant K is given by K = kR, where k is the specific conductance of thestandard KCl solution at the temperature determined at the time of measurement,5 and R is the measured resistance in ohms of theKCl solution
39、. From the measured specific resistance value, calculate the cell constant K for each of the three KCl samples. K shouldneeds to be approximately 1.0 cm1. The three cell constant values shall be averaged as follows:K 5K11K21K3!/3 (1)No single value shall deviate from the mean value by more than 2 %.
40、13.2 Calculate the specific conductance S in ohm1, cm1 for each specimen and control as follows:S 5K/R (2)where:K = conductivity cell constant from 13.1, andR = measured resistance in ohms of the specimen or control from 12.7.13.3 Calculate the corrosivity index for each material tested. The corrosi
41、vity index is the average of the specific conductanceS for the replicate specimens of each material, and is calculated as follows:corrosivity index5S11S21S3!/3 (3)where S1, S2, and S3 are the calculated specific conductances of the three replicate specimens from 13.2.14. Report14.1 Report the follow
42、ing information:14.1.1 Dates of test,14.1.2 Identification of plastics or filler material,14.1.3 Temperature and total duration of test exposure,14.1.4 Three cell constant values (K1, K2, and K3) and the average cell constant K for the conductivity cell,14.1.5 The measured specific resistance R of e
43、ach specimen and each control,14.1.6 The calculated specific conductance S of each specimen and each control, and14.1.7 The calculated corrosivity index for each material in ohms1, cm1 106.15. Precision and Bias615.1 Table 1 is based on a round robin conducted in 1985, involving three materials test
44、ed by five laboratories. For eachmaterial, all the samples were prepared by one source, but each laboratory prepared the individual specimens that it tested. Eachtest result was based on one individual determination. Each laboratory obtained three test results for each material.15.2 In Table 1, for
45、the materials indicated, and for test results that are derived from testing three specimens:15.2.1 Sr is the within-laboratory standard deviation of the average; Ir = 2.83 Sr. (See 15.2.3 for application of Ir.)5 The k value may be obtained from Fig. 1.6 Supporting data are available from ASTM Headq
46、uarters. Request RR:D20-1126.D4350 15415.2.2 SR is the between-laboratory standard deviation of the average; IR = 2.83 SR. (See 15.2.4 for application of IR.)15.2.3 RepeatabilityIn comparing two test results for the same material, obtained by the same operator using the sameequipment on the same day
47、, judge those test results should be judged as not equivalent if they differ by more than the Ir valuevaluesfor that material and condition.15.2.4 ReproducibilityIn comparing two test results for the same material, obtained by different operators using differentequipment on different days, judge tho
48、se test results should be judged as not equivalent if they differ by more than the IR valuefor that material and condition. (This applies between different laboratories or between different equipment within the samelaboratory.)15.2.5 Any judgment in accordance with 15.2.3 and 15.2.4 will have an app
49、roximate 95 % (0.95) probability of being correct.15.2.6 Other formulations maycan give somewhat different results.15.3 For further information on the methodology used in this section, refer to Practice E691.15.4 There are no recognized standards on which to base an estimate of bias for this test method.16. Keywords16.1 corrosivity; plastics; fillersSUMMARY OF CHANGESCommittee D20 has identified the location of selected changes to this standard since the last issue(D4350 - 00D4350 - 13(2005) that may impact the use of this sta
