1、Designation: D 2024 65 (Reapproved 2003)Standard Test Method forCloud Point of Nonionic Surfactants1This standard is issued under the fixed designation D 2024; 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.1. Scope1.1 This test method covers the determination of the solu-bility inversion temperature or “cloud point” of nonionicsurfactants or de
3、tergent systems which are characteristicallyless soluble in water at higher temperatures than at lowertemperatures. It is limited to those surfactants and detergentsystems for which the visible solubility change occurs over arange of 1C or less at concentrations of 0.5 to 1.0 % in waterbetween 30 an
4、d 95C.1.2 Chemical LimitationsNonionic surfactants that ex-hibit a characteristic cloud point in general terms consist of awater-in-soluble moiety condensed with 50 to 75 % by weightof ethylene oxide.1.3 This standard does not purport to address all of thesafety concerns, if any, associated with its
5、 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:2E 1 Specification for ASTM Thermometers3. Significance and Use3.1 The cl
6、oud point temperature is a reproducible charac-teristic of certain pure nonionic surfactants. It is also charac-teristic of certain nonionic surfactant formulated systems. Thistest method is appropriate for both systems.NOTE 1If the transition from a distinctly cloudy to a clear solution isnot sharp
7、, that is, if it does not take place within a range of 1C, this testmethod is not appropriate.4. Interferences4.1 Ionic surfactants or detergents in concentrations down to1 % or less of the nonionic surfactant drastically raise thecharacteristic cloud point of the latter. The presence of salts andba
8、ses (that is, non-surface active materials) will lower thecharacteristic cloud point. Acids tend to raise the cloud point.5. Apparatus5.1 ThermometerAn ASTM Partial Immersion Thermom-eter having a range from 20 to +150C or 0 to 302F andconforming to the requirements for Thermometer 1C or 1F inaccord
9、ance with Specification E 1.6. Procedure6.1 Prepare a 1.0 % test solution by weighing a 1 6 0.1-gsample into a 150-mL beaker and add 100 mL of distilled ordemineralized water which is at a temperature of less than30C. Agitate until the sample is dissolved. Pour 50 6 5mLoftest solution into a 25 by 2
10、00-mm test tube of borosilicateglass. While agitating the test solution slowly with the ther-mometer, heat the test tube with a bunsen burner until the testsolution becomes definitely cloudy. Remove from heat. Whilestirring slowly with the thermometer, allow the test solution tocool slowly until it
11、becomes clear. Record the temperature(Note 1).7. Precision7.1 The following precision data provide a reasonable basisfor judging the significance of the results:7.1.1 RepeatabilityDuplicate results by the same operatorshould not be considered suspect unless they differ by morethan 0.5C.7.1.2 Reprodu
12、cibilityThe average result reported by onelaboratory should not be considered suspect unless it differsfrom that of another laboratory by more than 1.0C.1This test method is under the jurisdiction of ASTM Committee D12 on Soapsand Other Detergents and is the direct responsibility of Subcommittee D 1
13、2.15 onPhysical Testing.Current edition approved Aug. 31, 1965. Published October 1965. Originallypublished as D 2024 62 T. Last previous edition D 2024 62 T.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of A
14、STMStandards volume information, refer to the standards Document Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.ASTM International takes no position respecting the validity of any patent rights assert
15、ed 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 infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by t
16、he 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 for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive
17、 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 known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM Interna
18、tional, 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 2024 65 (2003)2
