ASTM_D_6226_-_15.pdf

Designation:D622615Standard Test Method forOpen Cell Content of Rigid Cellular Plastics1This standard is issued under the fixed designation D6226;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,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.Scope1.1 This test method covers cellular plastics,which arecomposed of membranes or walls of polymer separating smallcavities or cells.These cells may be interconnecting(opencell),non-connecting(closed cell),or any combination of thesetypes.This test method determines numerical values for opencells.It is a porosity determination,measuring the accessiblecellular volume of a material.The remaining volume is thatoccupied by closed cells and cell walls.Since any convenientlysized specimen is typically obtained by some cutting operation,a fraction of the closed cells will be opened by specimenpreparation and will be included as open cells,(see Note 2).1.2 This test method provides good accuracy on predomi-nantly highly open-celled materials.By not accounting forclosed cells that were opened during specimen preparation,theaccuracy decreases as the closed cell content increases and asthe cell size increases.1.3 The values as stated in SI units are to be regarded as thestandard.The values in parentheses are given for referenceonly.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 limitations prior to use.NOTE1This test method and ISO 4590 use the same basic principlesbut are significantly different in experimental detail.NOTE2Two procedures for correcting for cells opened duringspecimen preparation are described in Appendix X1.1.2.Referenced Documents2.1 ASTM Standards:2D883 Terminology Relating to PlasticsD2842 Test Method for Water Absorption of Rigid CellularPlasticsD3576 Test Method for Cell Size of Rigid Cellular PlasticsE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method2.2 ISO Standard:ISO 4590 Cellular PlasticsDetermination of Volume Per-centage of Open and Closed Cells of Rigid Materials33.Terminology3.1 Definitions:3.1.1 Terms relating to plastics as given in TerminologyD883 shall be used where applicable.3.2 Definitions of Terms Specific to This Standard:3.2.1 closed cella cell totally enclosed by its walls andhence not interconnecting with other cells.3.2.2 open cella cell not totally enclosed by its walls andopen to the surface either directly or by interconnecting withother cells.3.2.3 volume of closed cells and cell wallsinaccessibleinternal volume,consisting of an aggregate of solid polymervolume(cell walls,struts),filler volume,when applicable(solid particles or fibers),the volume of individual closed cells,and the volume of small cell groups interconnected by rupturedcell walls but otherwise inaccessible.3.2.4 uncorrected volume of open cellsthe aggregate mea-surement of both the internal porous volume of the materialand the various irregular volumes accessible at the cut-cellsurface of the test specimen.3.3 Symbols:3.3.1 dspecimen diameter,cm.3.3.2 hspecimen height,cm.3.3.3 lspecimen length,cm.3.3.4 Ovvolume,percent open cells.3.3.5 Vgeometric volume of specimen,cm3.3.3.6 VCALIBvolume of the calibration standard,cm3.3.3.7 VCHAMBERvolume of the sample chamber,cm3.1This test method is under the jurisdiction of ASTM Committee D20 on Plasticsand is the direct responsibility of Subcommittee D20.22 on Cellular Materials-Plastics and Elastomers.Current edition approved Sept.1,2015.Published September 2015.Originallyapproved in 1998.Last previous edition approved in 2010 as D6226-10.DOI:10.1520/D6226-15.2For 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.3Available from American National Standards Institute(ANSI),25 W.43rd St.,4th Floor,New York,NY 10036.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 3.3.8 VEXPexpansion reference volume,cm3.3.3.9 VSPECspecimen displacement volume,cm3,and,3.3.10 wspecimen width,cm.4.Summary of Test Method4.1 This test method is based on a determination of porosityin which the accessible cellular volume of a cellular plastic isdetermined by application of Boyles Law,which states thatthe increase in volume of a confined gas results in a propor-tionate decrease in pressure.The apparatus consists of twochambers of known volume connected by a valve.One of thechambers,the calibrated sample chamber,is accessible forinsertion of the test specimen and is conne