1、Designation: D 3643 98 (Reapproved 2004)Standard Test Method forAcid Number of Certain Alkali-Soluble Resins1This standard is issued under the fixed designation D 3643; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of la
2、st 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 covers the measurement of the freeacidity present in certain alkali-soluble resins.1.2 This test metho
3、d is not suitable for styrene-maleicanhydride resins.1.3 The resin manufacturer should specify whether or notthis test method may be used for his product(s).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 o
4、f this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D 362 Specification for Industrial Grade TolueneD 1152 Specification for Methanol (Methyl Alcohol)D 1193 Specificat
5、ion for Reagent Water3. Terminology3.1 Definition:3.1.1 acid numberthe number of milligrams of potassiumhydroxide (KOH) required to neutralize the alkali-reactivegroups in1gofmaterial under the conditions of test.3.1.1.1 DiscussionIf carboxylic anhydrides are present,only one half of these groups wi
6、ll be titrated and indicated bythis test method.4. Significance and Use4.1 This test method is used to determine the property ofmaleic anhydride resins functionality. Maleic acid anhydrideresins functionality determines the utility of resin as well asbeing a significant quality control test.5. Reage
7、nts and Materials5.1 Purity of ReagentsReagent grade chemicals shall beused in all tests. Unless otherwise indicated, it is intended thatall reagents shall conform to the specifications of the Commit-tee on Analytical Reagents of the American Chemical Society,where such specifications are available.
8、3Other 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.5.2 Purity of WaterUnless otherwise indicated, referencesto water shall be understood to mean reagent water conformingto Spec
9、ification D 1193.5.3 Neutral Solvent MixtureMix equal parts of denaturedalcohol and industrial toluene conforming respectively to therequirements described for SDA. 3A (200 proof) and Specifi-cation D 362. Neutralize the mixture using 0.1 N KOH solutionand phenolphthalein indicator solution, until t
10、he faint pinkcolor persists for 1 min.5.4 Phenolphthalein Indicator Solution (10 g/L)Dissolve1.0 g of phenolphthalein in 100 mL of denatured alcohol (SDA3A, 200 proof).5.5 Potassium Hydroxide, Methyl Alcohol Solution (1mL = 5.6 mg KOH)Dissolve 6.6 g of potassium hydroxide(KOH) in 1 L of methyl alcoh
11、ol conforming to the require-ments described in Specification D 1152. Standardize againstNational Institute of Standards and Technology standardsample of acid potassium phthalate No. 84, using phenolphtha-lein as the indicator. Do not adjust the concentration of thesolution, but calculate the millig
12、rams of KOH per L ofsolution.6. Procedure6.1 Weigh or transfer into a 250-mL Erlenmeyer flask 0.5 gof crushed resin to the nearest 0.001 g.1This test method is under the jurisdiction of ASTM Committee D21 on Polishesand is the direct responsibility of Subcommittee D21.02 on Raw Materials.Current edi
13、tion approved Sept. 1, 2004. Published September 2004. Originallyapproved in 1978. Last previous edition approved in 1998 as D 3643 98.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume inf
14、ormation, refer to the standards Document Summary page onthe ASTM website.3Reagent Chemicals, American Chemical Society Specifications, AmericanChemical Society, Washington, DC. For suggestions on the testing of reagents notlisted by the American Chemical Society, see Analar Standards for Laboratory
15、Chemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeiaand National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,MD.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.6.2 Add 100 mL of neutral so
16、lvent. Mix until all material isdissolved. Add 3 to 5 drops of phenolphthalein indicatorsolution and titrate to the end point, a faint pink color whichpersists for 1 min.7. Calculation7.1 Calculate the acid number as follows:Acid number5AB/WA = millilitres of KOH solution required for titration of t
17、hesample,B = milligrams of KOH per millilitre of KOH solution,andW = grams of resin used.8. Report8.1 Report the acid number of resin tested, to the nearestwhole number.9. Precision and Bias9.1 PrecisionDuplicate results by the same operator shallnot be considered suspect unless they differ by more
18、than 65units.9.2 BiasThis test has no bias because the values producedare defined only in terms of this test method.10. Keywords10.1 acid number; alkali-soluble resins; free acid; polish;resins; titrationASTM International takes no position respecting the validity of any patent rights asserted in co
19、nnection 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 riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the respo
20、nsible technical committee and must be reviewed every 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
21、 consideration at 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,
22、100 Barr Harbor 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).D 3643 98 (2004)2
