1、Designation: D3643 10Standard Test Method forAcid Number of Certain Alkali-Soluble Resins1This standard is issued under the fixed designation D3643; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A numbe
2、r 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 measurement of the freeacidity present in certain alkali-soluble resins.1.2 This test method is not suitable for
3、 styrene-maleicanhydride resins.1.3 The resin manufacturer should specify whether or notthis test method may be used for his product(s).1.4 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.5 This standard does not purport to ad
4、dress 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 of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D362 Specifi
5、cation for Industrial Grade TolueneD1152 Specification for Methanol (Methyl Alcohol)D1193 Specification 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 condit
6、ions of test.3.1.1.1 DiscussionIf carboxylic anhydrides are present,only one half of these groups will 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 funct
7、ionality determines the utility of resin as well asbeing a significant quality control test.5. Reagents 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-
8、tee on Analytical Reagents of the American Chemical Society,where such specifications are available.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
9、 otherwise indicated, referencesto water shall be understood to mean reagent water conformingto Specification D1193.5.3 Neutral Solvent MixtureMix equal parts of denaturedalcohol and industrial toluene conforming respectively to therequirements described for SDA. 3A (200 proof) and Specifi-cation D3
10、62. Neutralize the mixture using 0.1 N KOH solutionand phenolphthalein indicator solution, until the 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 Al
11、cohol Solution (1mL = 5.6 mg KOH)Dissolve 6.6 g of potassium hydroxide(KOH) in 1 L of methyl alcohol conforming to the require-ments described in Specification D1152. Standardize againstNational Institute of Standards and Technology standardsample of acid potassium phthalate No. 84, using phenolphth
12、a-lein as the indicator. Do not adjust the concentration of thesolution, but calculate the milligrams 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.6.2 Add 100 mL of neutral solvent. Mix until all material isdiss
13、olved. Add 3 to 5 drops of phenolphthalein indicatorsolution and titrate to the end point, a faint pink color whichpersists for 1 min.1This test method is under the jurisdiction ofASTM Committee D21 on Polishesand is the direct responsibility of Subcommittee D21.02 on Raw Materials.Current edition a
14、pproved May 1, 2010. Published June 2010. Originallyapproved in 1978. Last previous edition approved in 2004 as D3643 98(2004).DOI: 10.1520/D3643-10.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStanda
15、rds volume information, 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
16、for LaboratoryChemicals, 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.7. Calculation
17、7.1 Calculate the acid number as follows:Acid number 5 A! 0.1N! 56.1!/CA = millilitres of alkali solution required for titration of thesample,N = normality of the alkali solution, andC = grams of resin used.8. Report8.1 Report the acid number of resin tested, to the nearestwhole number.9. Precision
18、and Bias9.1 PrecisionDuplicate results by the same operator shallnot be considered suspect unless they differ by more 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; po
19、lish;resins; titrationASTM 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 riskof infringeme
20、nt 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 every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or
21、for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful 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 kno
22、wn 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 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 ASTM website (www.astm.org/COPYRIGHT/).D3643 102
