1、Designation: D 4789 03Standard Test Method forSolution Color of Bisphenol A (4,4*-Isopropylidenediphenol)1This standard is issued under the fixed designation D 4789; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last
2、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. Scope1.1 This test method describes the procedure for determina-tion of the Platinum-Cobalt Color of 4,48-Isopropylidenediphenol, c
3、ommercially known as bisphenol A,dissolved in methanol.1.2 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 appro-priate safety and health practices and determine the applica-bility
4、 of regulatory limitations prior to use. For a specifichazard statement, see Section 8.2. Referenced Documents2.1 ASTM Standards:D 1209 Test Method for Color of Clear Liquids (Platinum-Cobalt Scale)2D 4297 Practice for Sampling and Handling 4,48-Isopropylidenediphenol (Bisphenol A)2E 180 Practice fo
5、r Determining the Precision of ASTMMethods for Analysis and Testing of Industrial and Spe-cialty Chemicals32.2 Other Documents:OSHA Regulations, 29 CFR, paragraphs 1910.1000 and1910.12004NIST Letter Circular LC 1017, Standard for Checking theCalibration of Spectrophotometers (200 to 1000 nm)53. Summ
6、ary of Test Method3.1 Bisphenol A is dissolved in methanol. This solution isthen transferred to a color comparison tube and the colorcompared to that of the Platinum-Cobalt Color Standards,either visually or by means of a spectrophotometer. The coloris reported as that closest to the applicable stan
7、dard.4. Significance and Use4.1 Color is caused by impurities in the bisphenol A. Theacceptable amount of color depends on the end-use of thebisphenol A.4.2 This test method can be used for internal quality controlor for setting specifications.5. Interferences5.1 The presence of any turbidity or haz
8、e will affect thecolor reading.5.2 A bisphenol A color that is off-hue, or tinted with respectto the color standards, may interfere with proper color com-parison.6. Apparatus6.1 Color Comparison TubesMatched 100 mL, tall-formNessler tubes, provided with ground-on, optically clear, glasscaps. Tubes s
9、hould be selected so that the height of the 100-mLgraduation mark is 275 to 295 mm above the bottom of thetube.6.2 Color Comparator, constructed to permit visual com-parison of light transmitted through tall-form, 100 mL Nesslertubes in the direction of their longitudinal axis; and so thatwhite ligh
10、t is passed through or reflected off a white glass plateand directed with equal intensity through the tubes. It should beshielded so that no light enters the tubes from the sides.6.3 Spectrophotometer, equipped for liquid samples and formeasurements in the visible region.NOTE 1The spectrophotometer
11、must be clean and in excellent oper-ating condition. The instrument should be calibrated in accordance withthe instructions given in NIST Letter Circular LC 1017. For goodagreement with the visual method, the spectrophotometer or colorimetershould be a filter type instrument.6.4 Spectrophotometer Ce
12、lls, cells of different path lengthsmay be used as long as the equipment is calibrated with thesame length cells as the sample solution.6.5 Filter Paper, glass fiber filter, 1.2-m pore retention.7. Reagents7.1 Purity of ReagentsReagent grade chemicals shall beused in all tests. Unless otherwise indi
13、cated, it is intended thatall reagents shall conform to the specifications of the Commit-tee on Analytical Reagents of the American Chemical Society,1This test method is under the jurisdiction of ASTM Committee D16 onAromatic Hydrocarbons and Related Chemicals and is the direct responsibility ofSubc
14、ommittee D16.02 on Oxygenated Aromatics.Current edition approved Jan. 10, 2003. Published March 2003. Originallyapproved in 1988. Last previous edition approved in 1994 as D 4789 94.2Annual Book of ASTM Standards, Vol 06.04.3Annual Book of ASTM Standards, Vol 15.05.4Available from U.S. Government Pr
15、inting Office Superintendent of Documents,732 N. Capitol St., NW, Mail Stop: SDE, Washington, DC 20401.5Available from National Institute of Standards and Technology (NIST), 100Bureau Dr., Stop 3460, Gaithersburg, MD 20899-3460.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West
16、Conshohocken, PA 19428-2959, United States.where such specifications are available.6Other grades may beused, provided it is first ascertained that the reagent is ofsufficiently high purity to permit its use without lessening theaccuracy of the determination.7.2 MethanolCheck for color against deioni
17、zed water; ifthe methanol is not water white, redistill in an all-glass system.7.3 Platinum-Cobalt Color StandardsPrepared accordingto Test Method D 1209.8. Hazards8.1 Consult current OSHA regulations, suppliers MaterialSafety Data Sheets, and local regulations for all materialsutilized in this test
18、 method.9. Sampling9.1 Sample the material in accordance with PracticeD 4297.10. Procedure10.1 Weigh 50 g of bisphenol A. Transfer to a 150-mLErlenmeyer flask.10.2 Measure 70 mL of methanol. Add to the Erlenmeyerflask containing the bisphenol A.10.3 Stir until all the bisphenol A is dissolved.10.4 T
19、ransfer the methanol solution to a color comparisontube, fill to the 100-mL mark, and cap the tube.10.5 If there is any visible turbidity, pass the methanolsolution through a filter and refill the comparison tube.10.6 Visually compare the methanol solution comparisontube with the color standards. A
20、spectrophotometer can be usedto determine the transmittance at a wavelength of 436 nm,which would be an indication of the color intensity.10.7 If a timed color development test is run, measure thecolor 30 min after the bisphenol A is dissolved in the methanol.(WarningUse of a spectrophotometer may p
21、rovide valueswhich are higher or inconsistent with those obtained by usingcolor comparison tubes.)11. Report11.1 Report the following information:11.1.1 The number of the standard that most nearly matchesthe specimen. If the color lies midway between two standards,report the darker of the two.11.1.2
22、 The result to the nearest 5 units. Duplicate runs thatagree within 10 units absolute are acceptable for averaging(95 % confidence level).11.2 If there is a difference in hue between the specimensand the standards, and a definite match cannot be made, reportthe range over which an apparent match is
23、obtained, and reportthe material as “off-hue.”12. Precision and Bias712.1 PrecisionThe precision estimates are based upon aninterlaboratory study on three specimens of bisphenol A fromthree different sources. One analyst in each of six laboratoriesperformed duplicate determinations and repeated on a
24、 secondday, for a total of 72 determinations. Practice E 180 was usedin developing these precision estimates.12.1.1 Intermediate Precision, previously called Repeat-ability (Single Analyst)The standard deviation of results(each the average of duplicate determinations), obtained by thesame analyst on
25、 different days, was estimated to be 2.0 unitsabsolute at 18 df. Two such averages should be consideredsuspect (95 % confidence level) if they differ by more than 10units absolute.12.1.2 Reproducibility (Multilaboratory)The standard de-viation of results (each the average of duplicate determina-tion
26、s), obtained by analysts in different laboratories has beenestimated to be 9.0 units absolute at 5 df. Two such averagesshould be considered suspect (95 % confidence level) if theydiffer by more than 35 units absolute.12.2 BiasSince there is no accepted reference materialsuitable for determining the
27、 bias in this test method formeasuring solution color, bias has not been determined.13. Keywords13.1 bisphenol A; color; color test; isopropylidenediphenolASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard.
28、 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 responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed e
29、very 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 addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible tec
30、hnical 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 the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshoho
31、cken, 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).6Reagent Chemicals, Americ
32、an Chemical Society Specifications, AmericanChemical Society, Washington, DC. For suggestions on the testing of reagents notlisted by the American Chemical Society, see Analar Standards for LaboratoryChemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeiaand National Formulary, U.S. Pharmaceutical Convention, Inc. (USPC), Rockville,MD.7Supporting data are available from ASTM Headquarters. Request RR:D16-1010.D4789032
