1、Designation: D5666 95 (Reapproved 2014)Standard Test Method forRubber Chemical AntidegradantsPurity of p-Phenylenediamine (PPD) Antidegradants by HighPerformance Liquid Chromatography1This standard is issued under the fixed designation D5666; the number immediately following the designation indicate
2、s the year oforiginal 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. Scope1.1 This test method covers the purity of Type I,
3、II, and IIIp-phenylenediamine (PPD) antidegradants as described inClassification D4676 by high performance liquid chromatog-raphy (HPLC) using ultraviolet detection and external standardcalculations.1.2 Expertise in HPLC is necessary to the successful appli-cation of this test method.1.3 The values
4、stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.4 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
5、 and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D3853 Terminology Relating to Rubber and RubberLaticesAbbreviations for Chemicals Used in Com-poundingD4483 Practice for Evaluating Precision for Test MethodStanda
6、rds in the Rubber and Carbon Black ManufacturingIndustriesD4676 Classification for Rubber Compounding MaterialsAntidegradants2.2 ISO Standards:3ISO 5725 Precision of Test MethodsISO 6472 Rubber Compounding IngredientsAbbreviations3. Terminology3.1 Definitions:3.1.1 external standard calculationa met
7、hod of calculat-ing the percent composition by measuring the area of theanalyte peak, multiplying by a response factor, and dividing bythe sample concentration. All components are assumed to beresolved from the component of interest.3.1.2 lot samplea production sample representative of astandard pro
8、duction unit, normally referred to as the sample.3.1.3 specimenthe actual material used in the analysis,also known as the test portion. It must be representative of thelot sample.3.2 Abbreviations:3.2.1 The following abbreviations are in accordance withTerminology D3853 and ISO 6472:3.2.2 77PDN,N bi
9、s-(1,4-dimethylpentyl)-p-phenylene-diamine.3.2.3 DTPDN,N-ditolyl-p-phenylenediamine.3.2.4 IPPDN-isopropyl-N-phenyl- p-phenylenediamine.3.2.5 PPDp-phenylenediamine.3.2.6 6PPDN-(1,3 dimethylbutyl)-N-phenyl-p-phenyl-enediamine.4. Summary of Test Method4.1 A specimen is dissolved in acetonitrile and a f
10、ixed loopvolume is analyzed by isocratic HPLC using a thermostatedC18 reversed phase column and an ultraviolet (UV) detector.Peak areas are determined using a chromatographic integratoror laboratory data system with the amount of analyte beingdetermined by external calibration.5. Significance and Us
11、e5.1 This test method is designed to determine the purity ofp-phenylenediamine antidegradants.1This test method is under the jurisdiction of ASTM Committee D11 on Rubberand is the direct responsibility of Subcommittee D11.11 on Chemical Analysis.Current edition approved Aug. 1, 2014. Published Novem
12、ber 2014. Originallyapproved in 1995. Last previous edition approved in 2009 as D5666 95 (2009).DOI: 10.1520/D5666-95R14.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refe
13、r to the standards Document Summary page onthe ASTM website.3Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States15.2 Since the resul
14、ts of this test method are based on anintegrated peak area as determined by HPLC, it is assumed thatall analytes of interest are resolved from interfering peaks.6. Interferences6.1 Components co-eluting with the analyte of interest willcause erroneous results; thus it is required that the system bec
15、apable of providing a minimum of 10 000 theoretical plates.7. Apparatus7.1 Liquid Chromatograph, consisting of the following:7.1.1 Precision chromatographic pump,7.1.2 Variable wavelength UV detector,7.1.3 A method for thermostating the column at 35 6 1C,for example, a column oven or water jacket,7.
16、1.4 A fixed injector made of either a 20 mm3(L)rheodyne loop or an automatic sampler.7.2 HPLC Columns, consisting of:7.2.1 A precolumn packed with C18 grafted silica withparticle size of 35 to 40 m (100 to 150 mm), and7.2.2 A column of 10- to 15-cm length packed with C18grafted silica with particle
17、size of 3 to 5 m.7.3 Integrator/Data System, capable of determining abso-lute amounts of analyte of interest by means of integration ofdetector output versus time.7.4 Analytical Balance, capable of measuring within 60.01mg.7.5 Shaking Machine, or ultrasonic tank.7.6 Volumetric Flask, 100 cm3.7.7 Syr
18、inges, with rheodyne loop, 2 cm3.7.8 Clear Screw-Top Vials, with suitable septa, 125 cm3.8. Reagents and Materials8.1 Acetonitrile, HPLC grade.8.2 Ethanolamine, HPLC grade.8.3 Water, HPLC grade or double distilled water or water ofresistivity greater than 2 megohms/cm.9. Calibration and Standardizat
19、ion9.1 Aprimary standard of known purity is used to determinethe response factor for each analyte.10. Procedure10.1 Chromatographic Conditions:10.1.1 Determine the eluant phase composition and the flowrate by adjusting the chromatographic parameters for theparticular column chosen. The eluant phase
20、consists of theappropriate mixture of HPLC grade acetonitrile and HPLCgrade or equivalent water, both containing 0.2 kg/m3(g/L)ethanolamine or less according to the product to be tested.NOTE 1Different liquid chromatography columns may exhibit differ-ent elution characteristics. See Table 1 for sugg
21、ested chromatographicstarting parameters for analysis.10.2 DetectorMonitor the absorbance of the sample at theprescribed wavelength. The detector should be set to 1 absor-bance unit full scale (AUFS).10.3 Integrator/Data SystemThe integrator settingsshould be adjusted to give a full-scale response t
22、o 1 absorbanceunit (AU).10.4 Sample Storage Before AnalysisSamples must al-ways be stored in a refrigerator.10.5 Standard PreparationWeigh the clear vial to thenearest 0.1 mg, introduce approximately 20 mg of the standardusing a spatula and weigh the standard and vial to the nearest0.1 mg. Using a v
23、olumetric flask, add 100 cm3of acetonitrileto the vial. Stopper the vial so that it is hermetically sealedimmediately after adding the solvent. Dissolve the product at23 6 3C in the ultrasonic bath tank or on the shakingmachine. The standard must be analyzed within4hofbeingprepared.NOTE 2Preparation
24、 of StandardsThe analytical standards areprepared by multiple recrystallizations or distillations of the paraphe-nylenediamines. The procedure can be repeated until the desired purity isobtained. The purity of the standard is estimated by gradient HPLCanalysis of the impurities and differential ther
25、mal analysis (DTA). Theimpurities in the standard should be reestimated every 90 days by HPLC.The standard should be stored at 5C or lower.10.6 Sample PreparationTo ensure sample homogeneity,5 g of sample should be ground with a mortar and pestle.10.7 Sample Analysis:10.7.1 Weigh at least 20 mg to t
26、he nearest 0.1 mg of thesample in a clear vial and dissolve it in 100 cm3acetonitrilefollowing the procedure in 10.5. The sample must be analyzedwithin4hofbeing prepared.10.7.2 Injection of the Solutions:10.7.2.1 Manual MethodTake approximately 100 L ofthe solution using a syringe and inject a quant
27、ity greater thanthe volume of the rheodyne loop, that is, approximately 60 lfor a 20-l loop. Rinse the syringe with solvent and dry.10.7.2.2 Automatic MethodPut the flasks containing thesample and standard solutions in place and program theautomatic sampler.10.7.3 Chromatograph the samples using par
28、ameters asprescribed in 10.1.1.11. Calculation11.1 Response FactorCalculate the response factor for thestandard by dividing the concentration of the standard by themeasured area count and multiplying this by the purity of thestandard:RF 5 concentration/area count! 3% purity (1)NOTE 3Throughout the c
29、alculation the units of concentration must beTABLE 1 Suggested Chromatographic Starting ParametersN,N-dialkyl-paraphenylene-diamine77-PPDN-aryl-N-alkyl-paraphenylene-diamineIPPD6-PPDN,N-diaryl-paraphenylene-diamineDPPDDTPDEluant phase% acetonitrile 85 65 70% Water 15 35 30Ethanolamine (g/L) 0.2 0.1
30、0.1Flow rate (cm3/min) 1 1 1Wavelength (nm) 260 290 280D5666 95 (2014)2consistent (that is, kg/m3(mg/cm3).11.2 Product PurityTo determine the purity of theproduct, multiply the response factor by the measured areacount of the analyte and divide by the sample concentration:% purity 5 RF 3area count/s
31、ample concentration (2)12. Report12.1 Report percent paraphenylenediamine to the nearest0.1 %.13. Precision and Bias413.1 This precision and bias section has been prepared inaccordance with Practice D4483. Refer to Practice D4483 forterminology and other statistical details.13.1.1 The precision resu
32、lts in this precision and biassection give an estimate of the precision of this test methodwith the materials used in the particular interlaboratory pro-grams as described below. The precision parameters should notbe used for acceptance/rejection testing of any group ofmaterials without documentatio
33、n that they are applicable tothose particular materials and the specific testing protocols thatinclude this test method.13.2 These precision and bias data were obtained in aninterlaboratory test organized in France in 1992. In thisprogram one material was analyzed by 13 different laborato-ries. Six
34、measurements were taken over six days by one tothree operators. Statistical evaluation was carried out in accor-dance with ISO 5725-1986, which is equivalent to the calcu-lation algorithms of Practice D4483. The results from thisprecision and bias study are given in Table 2.13.3 RepeatabilityThe dif
35、ference between two single testresults (or determinations) found on identical test materialunder the repeatability conditions prescribed for a particulartest will exceed the repeatability (r), as given in Table 2,onanaverage of not more than once in twenty cases in the normaland correct operation of
36、 the test method.13.4 ReproducibilityThe difference between two singleand independent test results found by two operators workingunder prescribed reproducibility (R) conditions in differentlaboratories on identical test material will exceed the repro-ducibility (R), as given in Table 2, on an averag
37、e of not morethan once in twenty cases in the normal and correct operationof the test method.13.5 BiasSample impurities that are not resolved from theanalyte of interest will produce a falsely high result. There maybe other sources of bias that have not been determined.14. Keywords14.1 antidegradant
38、; high performance liquid chromatogra-phy; N-isopropl-N-phenyl-p-phenylenediamine (IPPD); N-(1,3 dimethylbutyl)-N-phenyl-p-phenylenediamine (6PPD); N,N bis-(1, 4-dimethylpentyl)-p-phenylenediamine (77PD); N,N-ditolyl-p-phenylenediamine (DTPD); p-phenylenediamine(PPD)APPENDIX(Nonmandatory Information
39、)X1. RECOMMENDATIONSX1.1 De-gas the eluents.X1.2 Use an appropriate guard column.X1.3 Acid-clean the glassware.X1.4 Keep the temperature of the samples and standard thesame.4Supporting data have been filed at ASTM International Headquarters and maybe obtained by requesting Research Report RR:D11-106
40、3.TABLE 2 Precision (Type 1)Paraphenylenediamine PurityMaterialMeanAlevelWithin laboratoriesBBetween laboratoriesBSrr (r) SRR (R)6PPD 95.27 0.335 0.948 0.995 0.441 1.248 1.31AMean level values (in percent).BSymbols are defined as follows:Sr= within laboratory standard deviation,r = repeatability (in
41、 measurement units),(r) = repeatability (in percent),SR= between laboratory standard deviation,R = reproducibility (in measurement units),(R) = reproducibility (in percent)D5666 95 (2014)3ASTM International takes no position respecting the validity of any patent rights asserted in connection with an
42、y 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 responsibility.This standard is subject to revision at any time by the responsible technical
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44、t 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 the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor
45、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). Permission rights to photocopy the standard may also be secured from the Copyright Clearance Center, 222Rosewood Drive, Danvers, MA 01923, Tel: (978) 646-2600; http:/ 95 (2014)4
