1、Designation: D 1726 03Standard Test Methods forHydrolyzable Chloride Content of Liquid Epoxy Resins1This standard is issued under the fixed designation D 1726; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revisi
2、on. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.1. Scope1.1 These test methods cover the determination of t
3、he easilyhydrolyzable chloride content of liquid epoxy resins which aredefined as the reaction product of a chlorohydrin and a di- orpolyfunctional phenolic compound.1.1.1 In Test Method A, the easily hydrolyzable chloride issaponified with potassium hydroxide and directly titrated withhydrochloric
4、acid. This test method can be used for concen-trations of 1 weight % and below.1.1.2 In Test Method B, the easily hydrolyzable chloride isagain saponified with potassium hydroxide, then titrated po-tentiometrically with silver nitrate. This test method can beused for concentrations of 5 to 2500 ppm
5、hydrolyzablechloride.1.2 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are for informationonly.1.3 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 stan
6、dard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use. For specific hazardstatements see Sections 9 and 15.2. Referenced Documents2.1 ASTM Standards:2D 329 Specification for AcetoneD 841 Specification for Nitration Grade To
7、lueneD 1193 Specification for Reagent WaterD 3620 Specification for Glacial Acetic AcidD 6440 Terminology Relating to Hydrocarbon ResinsE 691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method2.2 Other Documents:OSHA Regulations, 29 CFR, paragraphs 1910.1000
8、and1910.120033. Terminology3.1 For definitions relating to hydrocarbon resins see Ter-minology D 6440.4. Summary of Test Method4.1 The sample is refluxed in the presence of a knownamount of 0.1 N alcoholic potassium hydroxide. The amount ofpotassium hydroxide consumed in the hydrolysis is a measureo
9、f the hydrolyzable chloride content of the resin.5. Significance and Use5.1 The hydrolyzable chloride content of liquid epoxy resinsis an important variable in determining their reactivity and theproperties of coatings made from them. These test methodsmay be used to determine the hydrolyzable chlor
10、ide content ofmanufactured epoxy resins and confirm the stated hydrolyzablechloride content of purchased epoxy resins.6. Apparatus6.1 Reflux Apparatus, consisting of a 250-mL Erlenmeyerflask attached to a reflux condenser and a hot plate withvariable heat control.7. Purity of Reagents7.1 Purity of R
11、eagentsReagent grade chemicals shall beused in all tests. Unless otherwise indicated, it is intended thatall reagents shall conform to the specifications of the Commit-tee onAnalytical Reagents of theAmerican Chemical Society,4where such specifications are available. Other grades may beused, provide
12、d it is first ascertained that the reagent is ofsufficiently high purity to permit its use without lessening theaccuracy of the determination.1This test method is under the jurisdiction of ASTM Committee D01 on Paintand Related Coatings, Materials, and Applications and is the direct responsibility o
13、fSubcommittee D01.33 on Polymers and Resins.Current edition approved Dec. 1, 2003. Published January 2004. Originallyapproved in 1960. Last previous edition approved in 1990 as D 1726 90 (1996).2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at s
14、erviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from U.S. Government Printing Office Superintendent of Documents,732 N. Capitol St., NW, Mail Stop: SDE, Washington, DC 20401.4Reagent Chemicals, American C
15、hemical 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.
16、 Pharmacopeial Convention, Inc. (USPC), Rockville,MD.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.7.2 Purity of WaterUnless otherwise indicated, referencesto water shall be understood to mean reagent water conformingto Type II of
17、Specification D 1193.TEST METHOD A 1 Weight % and Below ofHydrolyzable Chloride8. Reagents and Materials8.1 Hydrochloric Acid, Standard (0.1 N)Dilute 9 mL ofconcentrated hydrochloric acid (HCl, sp gr 1.19) to 1 L withwater. Standardize against 0.25 g of sodium carbonate(Na2CO3) accurately weighed an
18、d dissolved in 75 to 100 mLofwater.8.2 Methyl Ethyl Ketone.8.3 Phenolphthalein Indicator SolutionDissolve1gofphenolphthalein in 100 mL of methanol, ethanol, or isopro-panol.8.4 Potassium Hydroxide, Alcohol Solution (0.1 N)Dissolve 5.5 to 6.0 g of potassium hydroxide (KOH) in 1 L ofmethanol (99 %) or
19、 ethanol conforming to Formula No. SD-30of the U.S. Bureau of Internal Revenue. No standardization ofthe solution is necessary.8.5 Toluene (WarningSee Section 9.), conforming toSpecification D 841.8.6 Boiling Chips.9. Hazards9.1 Consult the latest OSHAregulations, suppliers MaterialData Sheets, and
20、local regulations regarding all materials usedin this method.9.2 Hydrochloric acid and potassium hydroxide are corro-sive. Toluene and methyl ethyl ketone are flammable and theirvapors can be harmful. Precautions should be taken to avoidinhalation and skin or eye contact with these chemicals. Allsam
21、ple preparations should be done in a well ventilated area,such as a fume hood.10. Procedure10.1 Weigh to the nearest 1 mg, 6 to8gofneutral specimeninto a 250-mL glass-stoppered Erlenmeyer flask. By means ofa pipette, transfer 50.0 mL of 0.1 N alcoholic KOH solutioninto the flask and add 15 mL of tol
22、uene. Stopper the flask andswirl to mix. Add a few boiling aids and attach to the refluxcondenser on the hot plate.10.2 Allow the solution to reflux gently for 15 6 1 min. Atthe end of the reflux period, remove the flask from the hot plateand cool to room temperature with the condenser in place.10.3
23、 Remove the condenser, add 3 drops of phenolphthaleinindicator solution to the specimen, and titrate with 0.1 N HCl.The end point is taken when 1 drop changes the solution frompink to colorless.NOTE 1Add 100 mL of methyl ketone to the specimen if required toensure a homogeneous solution during titra
24、tion of the excess KOHsolution.10.4 Make a blank determination on the reagents followingthe same procedure but omitting the specimen.11. Calculation11.1 Calculate the weight percent hydrolyzable chloridecontent of the specimen as follows:H 5 V 2 B!N 3 3.55/W (1)where:H = weight percent hydrolyzable
25、chloride,B = HCl required for titration of the blank, mL,V = HCl required for titration of the hydrolyzed speci-men, mL,N = normality of the HCl,3.55 = grams of chlorine per milliequivalent multiplied bythe percentage factor of 100, andW = specimen weight, g.12. Precision12.1 The following criteria
26、should be used for judging theacceptability of results at the 95 % confidence level:12.1.1 RepeatabilityTwo results obtained by the sameoperator should be considered suspect if they differ by morethan 0.02 % absolute.12.1.2 ReproducibilityTwo results obtained by operatorsin different laboratories sh
27、ould be considered suspect if theydiffer by more than 0.05 weight %.TEST METHOD B 5-2500 PPM Hydrolyzable Chloride13. Apparatus13.1 Reflux Apparatus, consisting of a 250-mL Erlenmeyerflask attached to a reflux condensor.13.2 Hot Plate, with variable heat control.13.3 Magnetic Stirrer, with polytetra
28、fluoroethylene (PTFE)-coated stirring bar.13.4 Buret or Automatic Titrator.13.5 Silver Electrode or equivalent.13.6 Boiling Chips.14. Reagents and Material14.1 Acetone,(WarningSee Section 15.) conforming toSpecification D 329.14.2 Bromcresol Green Indicator Solution (0.1 %)Dissolve 0.1 g of bromcres
29、ol green in 100 mL of water.14.3 Nitric acid, (HNO3) (1 + 1) diluted with water.14.4 Potassium Hydroxide, alcohol solution (0.1 N)Dissolve 5.6 g of potassium hydroxide (KOH) in 1 mL ofmethanol (99 %) or ethanol conforming to Formula No. SD-30of the US Bureau of Internal Revenue. No standardization o
30、fthe solution is necessary.14.5 Silver Nitrate, alcohol solution (0.0025 N)Dissolve0.425 g of silver nitrate (AgNO3), weighed to the nearest 1 mg,in 1 L of methanol (99 %) or ethanol conforming to FormulaNo. SD-30 of the US Bureau of Internal Revenue. Standardizeagainst hydrochloric acid or sodium c
31、hloride solution (withtraceability to an NIST standard).14.6 Toluene,(WarningSee Section 15.) conforming toSpecification D 841.14.7 Glacial Acetic Acid,(WarningSee Section 15.)conforming to Specification D 3620.D172603215. Hazards15.1 Consult the latest OSHA regulations, suppliers Mate-rial Data She
32、ets, and local regulations regarding all materialsused in this method.15.2 Nitric acid, glacial acetic acid, potassium hydroxide,and silver nitrate are corrosive. Acetone and toluene areflammable and their vapors can be harmful. Precautions shouldbe taken to avoid inhalation and skin or eye contact
33、with thesechemicals. All sample preparations should be done in a wellventilated area, such as a fume hood.16. Procedure16.1 Weigh 2 to3gofspecimen, to the nearest 0.005 g, intoa 250-mL Erlenmeyer flask. Add 20 mL of toluene, 20 mL ofacetone, and 50 mL of 0.1 N alcoholic KOH. Swirl or mix untildissol
34、ution is complete.16.2 Add several boiling chips, connect the flask to thereflux condenser, and gently reflux for 15 6 1 min on a hotplate.16.3 Remove the hot plate from under the flask and allowthe flask and contents to cool to room temperature. Rinse downthe condenser with acetone then remove from
35、 the flask.16.4 Quantitatively transfer the contents of the flask to a250-mL beaker using acetone as wash solution. Dilute thesolution to about 125 mL with acetone, insert a stirring bar, andplace on a magnetic stirrer.16.5 Add five drops of bromcresol green indicator. Whilestirring add 1 + 1 nitric
36、 acid dropwise just until the permanentcolor changes from blue to yellow. Also, 50 mL of glacialacetic acid can be added instead of adding the nitric aciddropwise (glacial acetic acid is not as strong as nitric acid).(WarningIf you are using nitric acid, do not add an excessamount. Do not acidify th
37、e solution until ready to begin thetitration. Make certain that the solution is at room temperaturebefore acidifying. These cautions are necessary to prevent thechloride results from being low due to recombination with theresin.)16.6 Titrate with 0.0025 N silver nitrate using the combina-tion silver
38、 electrode and the automatic titrator or buret.16.7 Reflux a blank, which includes all components exceptthe sample, and titrate with 0.0025 N silver nitrate.17. Calculation17.1 Calculate the parts per million hydrolyzable chloridecontent of the specimen as follows:H 5 V 2 B!N 3 35.5 3 103#/Wwhere:H
39、= parts per million hydrolyzable chloride,B = AgNO3required for the titration of the blank,mL,V = AgNO3required for the titration of the hy-drolyzed specimen, mL,N = Normality of the AgNO3,35.5 3 103= grams of chlorine per milliequivalent multi-plied by the ppm conversion of 1 3 106, andW = specimen
40、 weight, g.18. Precision18.1 A liquid epoxy resin of approximately 150 ppm hydro-lyzable chloride was sampled and analyzed at five laboratoriesand seven analysts obtained the following results.18.1.1 RepeatabilityThe difference between two resultsobtained by the same analyst should not vary by more
41、than8.32 % at the 95 % confidence level.18.1.2 ReproducibilityThe difference between two re-sults, each the mean of two determinations, obtained byanalysts in different laboratories should not vary by more than15.88 % relative at the 95 % confidence level.19. Keywords19.1 hydrolyzable chloride; liqu
42、id epoxy resin; saponifiablechlorideASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the ris
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