1、Designation: D4350 15D4350 16Standard 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, called the corrosivity index, is an index of the likelihood that, in a humid atmosphere, metalsurfaces in contact with these materials can be corroded due to galvanic action or direct chemical at
4、tack.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, associated with its use. It is the responsibilityof the user of this standard to establish a
5、ppropriate 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 Practice for Conditioning Plastics for TestingD883 Terminology Relating to PlasticsD1
6、193 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-Ventilation OvensE691 Practice for Conducting an Interlaboratory Study to Determine the Preci
7、sion of a Test MethodE2251 Specification for Liquid-in-Glass ASTM Thermometers with Low-Hazard Precision Liquids3. Terminology3.1 Definitions of TermsFor definitions of terms used in this test method associated with plastics issues refer to theterminology contained in Terminology D883.4. Significanc
8、e and Use4.1 This test method provides a means for comparing the corrosive potential of plastics and fillers in humid atmospheres.4.2 This test method is intended for use in research and evaluation.5. Apparatus5.1 Conductance Bridge, Wheatstone type, with a range from 1 to 250 000- measured resistan
9、ce, a built-in potentiometer, a1000 6 50-cycles per second oscillator, and a sensitive null point indicator. The bridge shall be capable of measuring resistancewith an accuracy of 62 %.1 This test method is under the jurisdiction of ASTM Committee D20 on Plastics and is the direct responsibility of
10、Subcommittee D20.16 on Thermosetting Materials.Current edition approved June 1, 2015Nov. 1, 2016. Published June 2015November 2016. Originally approved in 1984. Last previous edition approved in 20132015 asD4350 - 13.D4350 - 15. DOI: 10.1520/D4350-15.10.1520/D4350-16.2 For referencedASTM standards,
11、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 ASTM website.This document is not an ASTM standard and is intended only to provide the user of an ASTM sta
12、ndard an indication of what changes have been made to the previous 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 AS
13、TM is to be considered the official document.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States15.2 Conductivity Cell, dip-type, micro, for solutions of medium conductance.
14、 The cell needs to have a cell constant ofapproximately 1.0 cm1. The borosilicate glass shall have a maximum 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
15、 rotating at 500-r/min maximum speed.5.4 Mill, such as laboratory Wiley cutting mill or equivalent.5.5 Sieves, 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.
16、7 Oven, forced-ventilation type, with uniformity of temperature within 61 % of the differential between oven and ambienttemperature, with a rate of ventilation of 100 to 200 air changes per hour, in accordance with Specification E145, Type IIA.3 The sole source of supply of the conductivity cell (Mo
17、del 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 a meeting
18、 of the responsible technical committee,1 which you may attend.FIG. 1 Specific Conductance of 0.0100 Demal KClD4350 1625.8 Thermometer, solid-stem, precision, ASTM No. 63C,S63C, in accordance with Specification E1E2251. Temperaturemeasuring devices with equivalent accuracy and characteristics, such
19、as RTDs and thermistors, are permitted. Additionally, use ofASTM No. S63C in accordance with Specification E2251 is acceptable.5.9 Chemical Glassware:5.9.1 Borosilicate Glass Flask, nominally 1000-mL size, with ground glass stopper.5.9.2 Borosilicate Glass Erlenmeyer Flask, 65-mL actual capacity to
20、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 stored in borosilicate glass bottles at 236 2C, the
21、 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 distilled water. The solution shall be stored in a bo
22、rosilicate 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 conductanceObtain the value versusk temperature is plotted in from Fig. 1.6.3 Grease, silicone, not sol
23、uble 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 components and special precautions a
24、re required in handling. Diligentlyfollow the manufacturers precautionary instructions and sound laboratory safety practices.8. Sampling8.1 Because of the diverse nature of plastics and fillers, and the various forms and packages commercially available, no standardmethods of sampling have been estab
25、lished. 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 Plastics, either prepared in accordance with the manufacturers directions, or as rec
26、eived from the manufacturer, shall bedrilled with a sharp drill at a rate not exceeding 27.5 mm/s (10.54-mm diameter drill at 500 r/min), and the drillings shall be groundin a mill. Care shall be exercised so as not to overheat the material when drilling or grinding, as overheating shall cause chang
27、esin 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.9.2 Fillers, shall be used as received from the manufacturer.10. Conditioning10.1 Unless otherwise specified, condition all specimens for a mini
28、mum of 40 h at the standard laboratory atmosphere (23 62C, 50 6 10 % relative humidity), 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 t
29、hree Erlenmeyer flasks. Prepare at least three flasks, without material,as controls 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 a
30、rethoroughly wetted.12.4 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 event4 Specific conductance v
31、alues 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., and Stokes, R. H., Academic Press, Inc., New York, 1955, pp. 9496.D4350 163the specimen shall be
32、discarded). Agitate the flasks 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
33、6 2C. Again agitatethe flasks 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 n
34、earest 0.1C of the liquid in 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 solutio
35、ns with a conductance bridge 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
36、 be madewithin 4 h after removal 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
37、 in ohms of theKCl solution. From the measured specific resistance value, calculate the cell constant K for each of the three KCl samples. K needsto 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 val
38、ue by more than 2 %.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
39、 tested. The corrosivity 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
40、.1 Report the following 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 specif
41、ic resistance R of each 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
42、three materials tested by five laboratories. For each5 The k value may be obtained from Fig. 1.6 Supporting data are available from ASTM Headquarters. Request RR:D20-1126.TABLE 1 Precision Values in the Units of 106 ohm1 cm1Material Average S r SR Ir IREpoxy 1 25.5 3.30 8.35 9.3 23.6Epoxy 2 30.0 1.8
43、0 7.23 5.1 20.5Epoxy 3 104.0 3.87 19.5 11.0 55.2D4350 164material, 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 materi
44、al.15.2 In Table 1, for 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.)15.2.2 SR is the between-laboratory standard deviation of the ave
45、rage; 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, judge those test results as not equivalent if they differ by more than the Ir values for that materia
46、l andcondition.15.2.4 ReproducibilityIn comparing two test results for the same material, obtained by different operators using differentequipment on different days, judge those test results as not equivalent if they differ by more than the IR value for that material andcondition. (This applies betw
47、een different laboratories or between different equipment within the same laboratory.)15.2.5 Any judgment in accordance with 15.2.3 and 15.2.4 will have an approximate 95 % (0.95) probability of being correct.15.2.6 Other formulations can give somewhat different results.15.3 For further information
48、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 stan
49、dard since the last issue (D4350 - 15)that may impact the use of this standard. (November 1, 2016)(1) Removed reference to Specification E1 from 2.1.(2) Replaced Specification E1 with Specification E2251 in 5.8.SUMMARY OF CHANGESCommittee D20 has identified the location of selected changes to this standard since the last issue (D4350 - 13)that may impact the use of this standard. (June 1, 2015)(1) Eliminated permissive language in 1.1.(2) Added references to Terminology D883 and Specification E2251 in 2.1.(3) Eliminated old Sec
