1、Designation: D1975 16Standard Test Method forEnvironmental Stress Crack Resistance of Plastic InjectionMolded Open Head Pails1This standard is issued under the fixed designation D1975; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision
2、, 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 provides procedures for an indicationof the environmental stress crack resistance of pl
3、astic injectionmolded open head pails, covers, and components as a summa-tion of the effects of container design, resin, manufacturingconditions, field performance, and other factors.1.2 This test method may be used to evaluate a containersresistance to mechanical failure by cracking when in thepres
4、ence of chemical and physical stresses.1.3 Two procedures are provided as follows:1.3.1 Procedure A, Specified Stress-Crack Resistance TestMethodThis procedure is particularly useful for qualitycontrol since the conditions of the test are specified.1.3.2 Procedure B, User Selected Stress-Crack Resis
5、tanceTest MethodThis procedure allows individual selection oftest levels and is particularly useful as a design and develop-ment tool.1.4 These procedures are not designed to test the ability ofthe cover gasketing material or closure to retain the testreagent. Loss or leakage of the reagent through
6、these openingsdoes not constitute container failure. However, this mayindicate an internal pressure loss that might affect test results.1.5 The values stated in inch-pound units are to be regardedas standard. The values given in parentheses are mathematicalconversions to SI units that are provided f
7、or information onlyand are not considered standard.1.6 This standard does not purport to address all of thesafety problems, 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
8、regulatory limitations prior to use. Specific warningstatements are given in 6.2, 10.2.3, 10.2.4, 10.2.6, and 10.2.8.2. Referenced Documents2.1 ASTM Standards:2D996 Terminology of Packaging and Distribution Environ-mentsD4332 Practice for Conditioning Containers, Packages, orPackaging Components for
9、 TestingE122 Practice for Calculating Sample Size to Estimate, WithSpecified Precision, the Average for a Characteristic of aLot or Process3. Terminology3.1 DefinitionsReference Terminology D996 for defini-tions applicable to this test method.3.2 Definitions of Terms Specific to This Standard:3.2.1
10、environmental stress crackan external or internalcrack that develops when a container is exposed to chemical orphysical stresses, or both.3.2.2 stress crack failureany environmental stress crackthat causes a loss or leakage of the test reagent shall beinterpreted as container failure.4. Summary of T
11、est Method4.1 The environmental stress-crack resistance is determinedby subjecting an injection molded open head pail and coverthat is filled and sealed with a stress-crack reagent to amechanical top load at elevated temperatures. The recom-mended minimum test duration shall be 14 days, or as specif
12、iedby the user. The time to stress-crack failure is observed.4.1.1 ProcedureAexposes a minimum of three containers tospecified levels of chemical and physical stresses.4.1.2 Procedure B exposes containers to varying chemicaland physical stresses based on the users knowledge andobjectives.5. Signific
13、ance and Use5.1 These procedures provide an indication of the environ-mental stress-crack resistance of injection molded open head1This test method is under the jurisdiction of ASTM Committee D10 onPackaging and is the direct responsibility of Subcommittee D10.21 on ShippingContainers and Systems -
14、Application of Performance Test Methods.Current edition approved June 1, 2016. Published July 2016. Originally approvedin 1991. Last previous edition approved in 2010 as D1975 95 (2010). DOI:10.1520/D1975-16.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Custome
15、r Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1pails, covers, and components from a se
16、lected group or lot.Provided the thermal history of each container is constant, thistest method may be used for determining the applicability ofvarious plastic resins and mold designs for injection molding ofopen head pails and covers.5.2 The environmental stress-crack that occurs is indicativeof wh
17、at results when a container is exposed to agents such assoaps, organics, or any surface active solutions while underenvironmental conditions of stress.5.3 Environmental stress-cracking is a mechanism ofchemical attack that is highly dependent upon the test reagent,resin, container manufacturing or p
18、rocessing history, exposuretemperature, applied stress, and other factors. The combinationof these factors may result in eventual stress-crack failure.5.4 Procedure A minimizes the potential for test variabilityby providing the user with rigidly defined test conditions. Thistest method may be used f
19、or production quality control ofinjection molded open head containers.5.5 Procedure B allows the user to select and evaluateextreme individual elements or the interaction of several testlevels on container performance. These conditions are estab-lished based on laboratory experience and available kn
20、owledgeof the distribution environment. This test method may be usedfor identifying critical stresses which could aid in containerdesign or help in minimizing the occurrence of these stressesduring distribution.5.6 This test method is intended only as a pass/fail proce-dure in accordance with the us
21、ers specification, or as agreedupon between the user and the supplier. It is not intended as apredictor or indicator of field performance regarding time tofailure.6. Apparatus6.1 Environmental ChamberThe environmental chambershould be capable of maintaining a temperature control of62.5F (61.4C) of s
22、et point. For best circulation and aconstant temperature throughout, a forced air system is recom-mended.6.2 Top LoadRequires a pail identical to the test pail befilled to rated capacity or weight and then nested above the testpail. Free weights are then placed above in amounts necessaryto equal the
23、 specified top load. A calibrated pneumatic orhydraulic cylinder may be substituted for the additional freeweights. (WarningThe potential exists for catastrophicstress-crack failure causing an instability of the applied topload. Precautionary steps should be taken (that is, throughrestraining or gui
24、ding of the top load) to reduce the chance forinjury to the operators or damage to the test chamber andsurrounding test containers.)7. Reagents7.1 Procedure A; Nonyl Phenoxypoly (Ethyleneoxy) EthanolSolutionPrepare a 10 % solution, by volume, of the stress-cracking agent3and water.NOTE 1Due to the v
25、iscosity of the stress-cracking agent, it is helpfulto prepare the solution at an elevated temperature. A maximum tempera-ture of 122F (50C) is an acceptable level provided caution is used toavoid prolonged heating and eventual volume losses.7.2 Procedure BAny reagent or proprietary product(liquid,
26、solid, etc.) that is potentially a stress-cracking agent.8. Sampling8.1 A minimum of three containers are required for this testmethod. When possible for direct comparison, the test contain-ers should be produced on the same equipment, including moldand under identical conditions from the same produ
27、ction lot. Itis suggested that test container resin, machine, mold, andmolding conditions be thoroughly documented to improvestatistical reliability of the test data. (Practice E122.)9. Conditioning9.1 Condition empty test containers at 73 6 2F (23 61.3C) 50 6 3 % relative humidity for 48 hours prio
28、r to testing(see Practice D4332).10. Procedure10.1 Procedure ASpecified Stress-Crack ResistanceMethod:10.1.1 Place the environmental chamber set point control at122 6 2F (50 6 1.3C) and allow it to reach equilibrium. Filleach test specimen to 98 % of the containers maximumvolumetric capacity (with c
29、over in place) with the test reagent.Apply the cover to the pail as specified by the manufacturesclosing instructions.10.1.2 Place test specimens in the environmental chamberon an even horizontal surface. Place an identical pail filled torated capacity with sand or water on top of each test specimen
30、.Apply additional weight (if needed) to the top of the pail filledwith sand or water to bring the total top load weight (sand orwater pail plus weight) up to the values specified in Table 1.Record the time and date the test was started.10.1.3 Inspect the test pails and covers daily for anyevidence o
31、f stress-crack failure. Inspection of the cover mayrequire the removal of the top load from the test container.Stress crack may be more easily detected by placing the pail on3The sole source of supply of the stress-cracking agent (nonyl phenoxypoly(ethyleneoxy) ethanol solution, known as IIgepal CO-
32、630 (Antanox CO-630)known to the committee at this time is Rhodia, Inc. Home, Personal Care andIndustrial Ingredients, CN 7500, 259 Prospect Plains Road, Cranbury, NJ085127500 (18887767337). If you are aware of alternative suppliers, pleaseprovide this information to ASTM International Headquarters.
33、 Your comments willreceive careful consideration at a meeting of the responsible technical committee,1which you may attend.D1975 162top of a moisture indicating medium, such as paper. Themoisture indicating medium will allow the detection of smallleaks that otherwise may evaporate. Record the time,
34、date, andlocation of any failure that occurs.10.2 Procedure BUser Selected Stress-Crack ResistanceMethod:10.2.1 The following are individual elements that mayattribute to the weakening of a polymer and eventual stress-crack failure. Use these guidelines in establishing and selectingtest intensity le
35、vels.10.2.2 Container Production TechniquesThe processingmethods involved with injection molding of a container mayhave an effect on environmental stress-crack resistance. Docu-ment all factors significant to the production of the testcontainers.NOTE 2Molded in stress resulting in warpage or dimensi
36、onal changescan alter the chemical resistance of some polymers.10.2.3 ReagentSelect a stress-crack agent or suspect prod-uct and fill each test container to 98 % of the containersmaximum volume capacity. (WarningIf the containers areonly partially filled, the potential exists for the development ofe
37、xcessive internal pressures that may affect test results andcreate unstable test conditions.)NOTE 3The concentration level of the reagent may affect the rate ofchemical reaction.10.2.4 Container PreparationApply the cover to the pailas specified by the manufactures closing instructions(WarningSome p
38、roducts may exhibit internal pressure as aresult of exposure to high temperatures. Review the productSafety Data Sheet (SDS) and incorporate vented closures whenrequired.)10.2.5 Temperature LevelSelect a temperature level basedon desired test durations or measured environmental condi-tions. Set oven
39、 and allow it to reach equilibrium.NOTE 4The chemical attack of a polymer may be accelerated byexposure to high temperatures. The effects of humidity on a polymer areundetermined.NOTE 5When information about the environment is unknown, evalu-ate containers using levels expressed in Procedure A in 10
40、.1.1.10.2.6 Test SurfacePlace test containers on a surface thatis representative of shipment and storage conditions (forexample, style of pallet). (WarningAn extreme test surfacemay cause catastrophic pail failure. Care should be taken toprevent reagent spillage and ensure top load stability.)NOTE 6
41、When information about the distribution surface is unknown,evaluate containers on a flat, horizontal surface.10.2.7 Applied Top LoadSelect a top load representativeof the specific gravity or density of the intended lading and themaximum container stack height achieved during warehousing.This value i
42、s calculated using the following formula:Determination of Top Load:W 5Hh2 1 3 C 3S.G. 38.34 lb/gal!1T.W. (1)where:H = required stack height, in.,h = height of one container, in.,C = container capacity, gal,S.G. = specific gravity of product,T.W. = sample tare weight, lb, andW = constant top load wei
43、ght, lb.or:M 5Hh2 1 3 C 3S.G. 31.00 kg/L!1T.W. (2)where:H = required stack height, mm,h = height of one container, mm,C = container capacity, L,S.G. = specific gravity of product,T.W. = sample tare weight, kg, andM = constant top load mass, kg.10.2.7.1 With the top load determined, place an identica
44、lpail filled with sand, water, test reagent, or product on top ofeach test container. Apply additional weight to reach thecalculated top load value. Record the time and date the test wasstarted.NOTE 7When the product specific gravity or maximum containerstack height are unknown, select a top load va
45、lue as specified in ProcedureAin10.1.2, and in Table 1.10.2.8 Frequency of EvaluationSelect a method of evalu-ation based on test data requirements (for example,“ Pass/Fail,”etc .). Inspection is performed by removal of top load atpredetermined intervals or by visual inspection only.(WarningAvoid op
46、erator injury during top load removal byproviding the inspector with protective clothing.)NOTE 8Test results may be affected by removing the top load (releaseof any built up internal pressure), improper renesting of test containers,placing a container on its side during inspection causing a coating
47、of thecover with reagent, if manual external pressure is applied duringinspection, or if concentration of the test regent increases during the testdue to evaporative loss.10.2.9 Test DurationSelect a duration for the test contain-ers exposure to the chemical and physical stresses by usinginternal or
48、 in-house requirements and test objectives.11. Report11.1 Report the following information:11.1.1 Procedure used (Procedure A or B).11.1.2 Complete description of the containers tested, includ-ing resin properties, injection molding conditions, pigmentloading levels, percent of regrind resin, percen
49、t of postconsumer resin, and any other available information.11.1.3 Number of containers tested.TABLE 1 Top Load Weight RequirementsTop LoadsPail Rated Capacity, gal (L)ATop Load Weight, lb (kg)3 (11.36) 120 (54.43)4 (15.14) 160 (72.58)5 (18.93) 200 (90.72)6 (22.71) 240 (108.86)AFor pails having a capacity other than those shown in Table 1, the top load iscalculated using the following equation: capacity in gallons (litres) 40 lb (4.792kg) = top load in pounds (kilograms).D1975 16311.1.4 Reagent or product description.11.1.5 T
