1、Designation:D 3272 76(Reapproved 2003)Standard Practice forVacuum Distillation of Solvents From Solvent-ReduciblePaints For Analysis1This standard is issued under the fixed designation D 3272;the number immediately following the designation indicates the year oforiginal adoption or,in the case of re
2、vision,the year of last revision.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 This practice covers a
3、 vacuum distillation procedure thatseparates the solvents from the nonvolatile portion of paints sothey may be analyzed.1.2 An alternative procedure for the analysis of solvents inpaints is described in Practice D 3271.1.3 The values stated in SI units are to be regarded as thestandard.The values gi
4、ven in parentheses are for informationonly.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 of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory
5、limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2D 3271 Practice for Direct Injection of Solvent-ReduciblePaints into a Gas Chromatograph for Solvent Analysis3.Summary of Practice3.1 The sample of whole paint with added tricresyl phos-phate is heated by means of a silicone oil bath
6、.The distillationis allowed to proceed for a period of time and then vacuum isapplied.Finally dry air is passed through the system tofacilitate the removal of any high-boiling solvents present.4.Apparatus4.1 Apparatus3is shown in Fig.1.It is essential in assem-bling this apparatus,that the volume of
7、 the portion precedingthe flask be kept to a minimum by using diameters ofconnections and distances as small as possible.Include a gagein the assembly for measuring pressure.4.2 Vacuum Pump,capable of pulling 2 mm Hg or less ofvacuum pressure.4.3 Septum Sample Vial,PTFE-fluorocarbon-faced.44.4 Safet
8、y Shield.5.Reagents5.1 Methylene Chloride or Acetone.5.2 Silicone Oil.55.3 Tricresyl Phosphate.6.Procedure6.1 Immerse the receiver in a bath containing dry ice withmethylene chloride or acetone of sufficient depth that the liquidreaches to the bottom level of the rubber stopper.6.2 Pour approximatel
9、y 15 g of the whole paint sample intothe 50-mL distillation flask.Immediately follow with 10 mL oftricresyl phosphate and without delay mix the contents of theflask.6.3 Assemble the apparatus and close the needle valve andstopcock attached to the capillary tubing.Immerse the distil-lation flask by r
10、aising a silicone oil bath preheated to 155 to160C(WarningCare should be taken to prevent the tem-perature of the silicone oil exceeding 160C because ofpossible formation of explosive mixtures of air and solventsfrom the sample being analyzed.)until it reaches the side arm(Note 1).Allow the distilla
11、tion to proceed for 15 min withoutvacuum.NOTE1The liquid level in the oil bath should be as high as ispractical.6.4 After 15 min apply vacuum slowly and carefully toavoid bumping or rapid distillation until 2 mm Hg is reached.1This practice is under the jurisdiction of ASTM Committee D01 on Paint an
12、dRelated Coatings,Materials,and Applications and is the direct responsibility ofSubcommittee D01.21 on Chemical Analysis of Paints and Paint Material.Current edition approved Dec.1,2003.Published December 2003.Originallyapproved in 1973.Last previous edition approved in 1976 as D 3272 76(1998).2For
13、referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.3Obtainable from SGA Scientific,Inc.,735 Broad St.,Bloomfield,NJ 07005.
14、4Septum vials available from Precision Sampling Corp.,Baton Rouge,LA70315,have been found satisfactory for this purpose.5The sole source of supply of silicone oil 710 known to the committee at thistime is Dow Corning Corp.,Midland,MI.If you are aware of alternative suppliers,please provide this info
15、rmation to ASTM International Headquarters.Your com-ments will receive careful consideration at a meeting of the responsible technicalcommittee,1which you may attend.1Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959,United States.This step should take ap
16、proximately 10 to 15 min.Next,carefully open the stopcock.After bubbling subsides,adjust theneedle valve so as to regulate the flow of air at a rate of 60 to80 bubbles per minute(at the bubble counter).Pass air throughthe system for a total of 30 min while keeping the dry ice bathat a minimum low temperature.6.5 At the end of the 30-min period release the vacuum veryslowly with air flowing to prevent back-up of the paint.Remove the receiver containing the solvents and warm thecontents only to th
