1、Designation:D256112Standard Test Method forEnvironmental Stress-Crack Resistance of Blow-MoldedPolyethylene Containers1This standard is issued under the fixed designation D2561;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year
2、 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 Under certain conditions of stress,and in the presence ofenvironments such as soaps,wetting agents,oils,or detergents,
3、blow-molded polyethylene containers exhibit mechanical fail-ure by cracking at stresses appreciably below those that wouldcause cracking in the absence of these environments.1.2 This test method measures the environmental stresscrack resistance of containers,which is the summation of theinfluence of
4、 container design,resin,blow-molding conditions,post treatment,or other factors that can affect this property.Three procedures are provided as follows:1.2.1 Procedure A,Stress-Crack Resistance of Containers toCommercial LiquidsThis procedure is particularly useful fordetermining the effect of contai
5、ner design on stress-crackresistance or the stress-crack resistance of a proposed commer-cial package containing a proprietary liquid product.1.2.2 Procedure B,Stress-Crack Resistance of a SpecificContainer to Polyoxyethylated Nonylphenol(CAS 68412-54-4),a Stress-Cracking AgentThe conditions of test
6、 describedin this procedure are designed for testing containers made fromClass 3 polyethylene Specification D4976.Therefore,thisprocedure is recommended for containers made from Class 3polyethylene only.This procedure is particularly useful fordetermining the effect of resin on the stress-crack resi
7、stance ofthe container.1.2.3 Procedure C,Controlled Elevated Pressure Stress-Crack Resistance of a Specific Container to PolyoxyethylatedNonylphenol(CAS 68412-54-4),a Stress-Cracking AgentThe internal pressure is controlled at a constant elevated level.NOTE1There are environmental concerns regarding
8、 the disposal ofPolyoxyethylated Nonylphenol(Nonylphenoxy poly(ethyleneoxy)etha-nol(CAS 68412-54-4),for example,Igepal CO-630).Users are advised toconsult their supplier or local environmental office and follow theguidelines provided for the proper disposal of this chemical.1.3 These procedures are
9、not designed to test the propensityfor environmental stress cracking in the neck of containers,such as when the neck is subjected to a controlled strain byinserting a plug.1.4 The values stated in SI units are to be regarded asstandard.NOTE2There is no known ISO equivalent to this standard.1.5 This
10、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.Specific precau-tionary sta
11、tements are given in Section 8 and Note 2 and Note9.2.Referenced Documents2.1 ASTM Standards:2D618 Practice for Conditioning Plastics for TestingD4976 Specification for Polyethylene Plastics Molding andExtrusion MaterialsD5947 Test Methods for Physical Dimensions of SolidPlastics SpecimensE145 Speci
12、fication for Gravity-Convection and Forced-Ventilation Ovens3.Terminology3.1 Definitions of Terms Specific to This Standard:3.2 failureduring this test method,the formation of anyimperfection,such as a crack,which results in a loss ofpressurizing gas or stress-cracking agent.3.2.1 DiscussionA contai
13、ner has failed when:It has lost pressure through any aperture other than heatseal areas;or,in Procedure C,when there is a detectable flowof supply air into the bottle,there is any visible crackcompletely through the container wall,there is evidence ofthe contained liquid on the outside of the contai
14、ner through1This test method is under the jurisdiction of ASTM Committee D20 on Plasticsand is the direct responsibility of Subcommittee D20.19 on Film,Sheeting,andMolded Products.Current edition approved Aug.1,2012.Published September 2012.Originallyapproved in 1966.Last previous edition approved i
15、n 2005 as D2561-95(2005).DOI:10.1520/D2561-12.2For 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.*A Summary of Change
16、s section appears at the end of this standardCopyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 any aperture other than one at the heat-seal area,or thecontained liquid volume has been reduced.4.Summary of Test Method4.1 Procedure A consists of exposing any filled,sealed,blow-molded container to the action of a potential stress-cracking agent within the container,at an elevated temperature.The time to failure is observed.4.2 Procedure B
