1、Designation: D4661 09D4661 13Standard Test Methods forPolyurethane Raw Materials: Determination of Total Chlorinein Isocyanates1This standard is issued under the fixed designation D4661; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revisi
2、on, 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. Scope*1.1 These test methods determine the total chlorine content of aromatic isocyanates used as polyurethane
3、raw materials. Thedifference between the total chlorine content and the hydrolyzable chlorine content (see Test Method D4663) is a measure of theamount of o-dichlorobenzene and other ring-substituted chlorinated products that are present. Both procedures are applicable toa variety of organic compoun
4、ds but the amount of sample used may have to be varied. (See Note 1.)1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its us
5、e. It is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.NOTE 1There is no equivalent ISO standard. known ISO equivalent to this standard.2. Referenced Documents2.1 ASTM Standard
6、s:2D883 Terminology Relating to PlasticsD1193 Specification for Reagent WaterD4663 Test Method for Polyurethane Raw Materials: Determination of Hydrolyzable Chlorine of Isocyanates3. Terminology3.1 DefinitionsFor definitions of terms used in these test methods see Terminology D883.4. Summary of Test
7、 Method4.1 In each test method, the organic matter in the sample is destroyed by combustion with oxygen, the organically combinedchlorine being converted to ionic chloride. The chloride is determined potentiometrically by titration with silver nitrate (AgNO3)solution.4.1.1 Test Method AThe sample is
8、 combusted in a pressurized oxygen bomb.4.1.2 Test Method BThe sample is combusted at atmospheric pressure in a Schniger oxygen flask.35. Significance and Use5.1 These test methods can be used for research or for quality control to determine the total chlorine content of aromaticisocyanates. In some
9、 instances total chlorine content may correlate with performance in polyurethane systems.6. Interferences6.1 Bromine and iodine, if present, will react with the silver nitrate (AgNO3) solution leading to an erroneously high totalchlorine value.1 These test methods are under the jurisdiction of ASTM
10、Committee D20 on Plastics and are the direct responsibility of Subcommittee D20.22 on Cellular Materials -Plastics and Elastomers.Current edition approved Feb. 1, 2009Nov. 1, 2013. Published March 2009November 2013. Originally approved in 1987. Last previous edition approved in 20032009 asD4661 - 03
11、.D4661 - 09. DOI: 10.1520/D4661-09.10.1520/D4661-13.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. ForAnnual Book ofASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.3 For infor
12、mation on the Schniger flask, refer to Microchemie, Springer Publishers, Vienna, Austria, Vol 42, 1955, p. 123, or Vol 43, 1956, p. 869.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous vers
13、ion. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.*A Summary of Changes sect
14、ion appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States17. Reagents and Materials7.1 Purity of ReagentsUse reagent-grade chemicals in all tests. Unless otherwise indicated, it is intended that all reagen
15、tsconform to the specifications of the Committee on Analytical Reagents of the American Chemical Society where suchspecifications are available.4 Other grades may be used, provided it is first ascertained that the reagent is of sufficiently high purityto permit its use without lessening the accuracy
16、 of the determination.7.2 Purity of WaterUnless otherwise indicated, references to water shall be understood to mean reagent water as defined byType I of Specification D1193.8. Sampling8.1 Since organic isocyanates react with atmospheric moisture, take special precautions in sampling. (WarningOrgani
17、cisocyanates are toxic when they are absorbed through the skin, or when the vapors are breathed. PrecautionProvide adequateventilation and wear protective gloves and eyeglasses.) Usual sampling methods (for example, sampling an open drum with athief), even when carried out Usual sampling methods, ev
18、en when conducted rapidly, can cause contamination of the sample withinsoluble urea. Therefore, blanket the sample with dry air or nitrogen at all times. (WarningMany diisocyanates are known orsuspected sensitizers. Over-exposure to diisocyanates can lead to adverse health effects, which include the
19、 development ofoccupational asthma and other respiratory, skin and eye effects. Engineering controls and/or personal protective equipment,including respiratory, skin and eye protection, are to be used when there is a potential for over-exposure to diisocyanates. Theproduct suppliers Safety Data Shee
20、t (SDS) provides more detailed information about potential adverse health effects and otherimportant safety and handling information. Always follow the specific instructions provided on the SDS.)9. Test Conditions9.1 Since isocyanates react with moisture, keep laboratory humidity low, preferably aro
21、und 50 % relative humidity. it is highlyrecommended that moisture be excluded from the sample.TEST METHOD ATOTAL CHLORINE BY OXYGEN BOMB10. Apparatus10.1 Weighing Bottle and Balance, suitable for weighing a liquid sample by difference to the nearest 0.5 mg. milligram.10.2 Oxygen Bomb Apparatus.510.3
22、 Fuse Wire, iron-nickel-chromium, No. 34 B chlorine; isocyanates; oxygen bomb; polyurethane raw materials; Schniger ignition; titration8 Arthur H. Thomas Co., Catalog No. 6513C05.D4661 135SUMMARY OF CHANGESCommittee D20 has identified the location of selected changes to this standard since the last
23、issue(D4661 - 03D4661 - 09) that may impact the use of this standard. (February(November 1, 2009)2013)(1) RemovedReplaced referenceSampling to specific titrator. Referenced model has been replaced and there are many otherscommercially available.section with wording consistent with the other polyuret
24、hane raw material methods.(2) Renumbered Footnotes 7-9 to reflect removal of Footnote 6.Removed recommendation for lab humidity.(3) Removed nonstandard concentration usage “1+1” throughout methods.(4) Removed duplicate calculation equations.(5) Renumbered footnotes.ASTM International takes no positi
25、on 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 infringement of such rights, are entirely their own responsibility
26、.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 for additional standardsand should be addressed to ASTM I
27、nternational 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 known to the ASTM Committee on Standards, at the address sho
28、wn 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/).D4661 136
