1、Designation:D 3272 76(Reapproved 1998)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 This standard does not purport to address all of thesafety concerns,if any,as
4、sociated 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:D 3271 Practice for Direct Injection of Solvent-ReducibleP
5、aints into a Gas Chromatograph for Solvent Analysis23.Summary of Practice3.1 The sample of whole paint with added tricresyl phos-phate is heated by means of a silicone oil bath.The distillationis allowed to proceed for a period of time and then vacuum isapplied.Finally dry air is passed through the
6、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 the portion precedingthe flask be kept to a minimum by using diameters ofconnections and distances as small as possible.Inc
7、lude 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 Safety Shield.5.Reagents5.1 Methylene Chloride or Acetone.5.2 Silicone Oil.55.3 Tricresyl Phosphate.6.Procedure6.1 Immerse the re
8、ceiver 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 approximately 15 g of the whole paint sample intothe 50-mL distillation flask.Immediately follow with 10 mL oftricresyl phosphate and wi
9、thout 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 raising a silicone oil bath preheated to 155 to160C(Warningsee Note 1)until it reaches the side arm(Note 2).Allow the distill
10、ation to proceed for 15 min withoutvacuum.NOTE1Warning:Care should be taken to prevent the temperature ofthe silicone oil exceeding 160C because of possible formation ofexplosive mixtures of air and solvents from the sample being analyzed.NOTE2The liquid level in the oil bath should be as high as is
11、practical.6.4 After 15 min apply vacuum slowly and carefully toavoid bumping or rapid distillation until 2 mm Hg is reached.This step should take approximately 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
12、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 contain
13、ing the solvents and warm thecontents only to the temperature of cold running tap water.Transfer the isolated solvents promptly to an airtight septum1This practice is under the jurisdiction of ASTM Committee D-1 on Paint andRelated Coatings,Materials,and Applications and is the direct responsibility
14、 ofSubcommittee D01.21 on Chemical Analysis of Paints and Paint Material.Current edition approved Oct.29,1976.Published December 1976.Originallypublished as D 3272 73 T.Last previous edition D 3272 73 T.2Annual Book of ASTM Standards,Vol 06.01.3Obtainable from SGA Scientific,Inc.,735 Broad St.,Bloom
15、field,NJ 07005.4Septum 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 pr
16、ovide this information toASTM Headquarters.Your comments will receivecareful consideration at a meeting of the responsible technical commitee,1whichyou may attend.1AMERICAN SOCIETY FOR TESTING AND MATERIALS100 Barr Harbor Dr.,West Conshohocken,PA 19428Reprinted from the Annual Book of ASTM Standards.Copyright ASTMfaced vial for subsequent analysis.7.Keywords7.1 solvents in paints;vacuum distillationThe American Society for Testing and Materials takes no position respecting the validity of any pa
