1、Designation: D 5227 01Standard Test Method forMeasurement of Hexane Extractable Content of Polyolefins1This standard is issued under the fixed designation D 5227; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last rev
2、ision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This test method describes an extraction/gravimetricprocedure for determination of the amount of hexane solublelow molecular
3、 weight material present in polyethylene,polypropylene, ethylene-propylene copolymers, and ethylene-vinyl acetate copolymers. This test method is a modification ofthe Food and Drug Administration (FDA) procedure fordetermining hexane extractables of polyolefins. This testmethod is based upon the pre
4、sumption that the weight of theresidue extract present in the solvent is equal to the amountextracted from the film sample and could therefore be quanti-fied by measuring the weight loss of the extracted film,eliminating the complex and time-consuming evaporationprocess described in 21 CFR 177.1520.
5、1.2 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.1.3 The values
6、stated in SI units are to be regarded as thestandard. Units used in 21 CFR 177.1520 are also used in thistest method. Units are in conformance with Federal Code 21CFR 177.1520, from which this test method is derived.NOTE 1There is no similar or equivalent ISO standard.2. Referenced Documents2.1 ASTM
7、 Standards:D 883 Terminology Relating to Plastics2D 1239 Test Method for Resistance of Plastics Fibers toExtraction by Chemicals2D 1600 Terminology for Abbreviated Terms Relating toPlastics2E 131 Terminology Relating to Molecular Spectroscopy3E 691 Practice for Conducting an Interlaboratory Study to
8、Determine the Precision of a Test Method42.2 Federal Document:521 CFR 177.15203. Terminology3.1 The definitions given in Terminology D 883, D 1600,and E 131 are applicable to this test method.3.2 Abbreviations:Abbreviations:3.2.1 EVAethylene-vinyl acetate copolymer.3.2.2 LDPElow-density polyethylene
9、.3.2.3 HDPEhigh-density polyethylene.3.2.4 LLDPElinear low-density polyethylene.3.2.5 FDAFood and Drug Administration.3.2.6 PPpolypropylene.4. Summary of Test Method4.1 Film samples are extracted with hexane for 2 h at 49.56 0.5C, dried, and weighed.4.2 The loss in weight of the film is presumed to
10、be equal tothe extractable content determined by solvent evaporation inthe FDA protocol.5. Significance and Use5.1 FDA requirements for maximum extractables are speci-fied for resin and uses. This test method provides a means todetermine the amount of hexane-soluble low molecular weightmaterial pres
11、ent in polyolefins. It is applicable to resinscontaining greater than 0.20 % extractables.6. Apparatus6.1 Water Bath, maintained at 49.5 6 0.5C.6.2 Resin Kettle, 1500-mL.66.3 Kettle Head, 3-neck, with one 45/50 and two 24/40female joints, and appropriate stoppers.76.4 Clamp.81This test method is und
12、er the jurisdiction of ASTM Committee D20 on Plasticsand is the direct responsibility of Subcommittee D20.70 on Analytical Methods.Current edition approved June 10, 2001. Published August 2001. Originallypublished as D 5227 92. Last previous edition D 5227 95.This edition includes revisions to Secti
13、on 10, Calculation.2Annual Book of ASTM Standards, Vol 08.01.3Annual Book of ASTM Standards, Vol 03.06.4Annual Book of ASTM Standards, Vol 14.02.5Available from Standardization Documents Order Desk, Bldg. 4 Section D, 700Robbins Ave., Philadelphia, PA 19111-5094. Attn: NPODS.6Ace Glass, Inc., Cat. N
14、o. 647615, or its equivalent, has been foundsatisfactory.7Ace Glass, Inc., Cat. No. 648640, or its equivalent, has been foundsatisfactory.8Ace Glass, Inc., Cat. No. 649610, or its equivalent, has been foundsatisfactory.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM
15、 International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.6.5 Allihn Condenser, Size C, with 45/50 male joint.96.6 Plastic Sleeves, tetrafluoroethylene (TFE), to fit Allihncondenser 45/50 male joint.6.7 Vacuum Oven, capable of maintaining 80 6 5C and aminimu
16、m of 25-in. Hg pressure.6.8 Magnetic Stirring Bar, egg-shaped, TFE-coated, 112 by58 in.6.9 Submersible Magnetic Stirring Motor, with power sup-ply.106.10 Analytical Balance, capable of weighing to 0.1 mg.7. Reagents and Materials7.1 n-Hexane, aromatic free (1 mg/L), minimum 85 %n-Hexane-reagent grad
17、e or equivalent.11The solvent must befree of aromatic compounds that would significantly increasethe solubility of the resin. The solvent grade specified repre-sents the minimum required purity.8. Materials8.1 Blown Film, compression molded films, or cast filmscan be tested.8.2 Film, approximately 2
18、.5 g, with a thickness not exceed-ing 4 mil is required for a single determination.9. Procedure9.1 Assemble the resin kettle setup with glass stopper,clamp, and magnetic stirring bar. (See Fig. 1.)9.2 Add 1000 mL of n-Hexane to the kettle assembly.9.3 Stopper the kettle and clamp the assembly into t
19、he waterbath set at 49.5 6 0.5C.NOTE 2Temperature is a critical factor in this analysis and must notvary more than 1C. If the temperature exceeds these limits, the test mustbe discontinued and restarted. The FDA protocol also states the tempera-ture of the contents must be brought to 49.5 6 0.5C wit
20、hin 20 to 25 min.NOTE 3The level of water in the bath must be kept at least 2 cm abovethe level of the solvent in the kettle to ensure the temperature equilibrium.Position the kettle so that the center bottle of the kettle is sitting on asubmersible stirrer. Start stirring and allow the hexane to he
21、at for 1 h.9.4 Using gloves and metal tweezers to avoid samplecontamination, cut about 2.7 g of the prepared film sample (4mil or less in thickness) into about 1-in. squares using cleansharp scissors.NOTE 4Care must be exercised when cutting the samples to avoidragged edges on the specimen. Small sh
22、ards of film or contaminationpresent at initial weighing can easily be lost during the test, adverselyaffecting the test results.9.5 Weigh 2.5 6 0.05 g of film squares and record the initialfilm weight to the nearest 0.1 mg. Also record the number offilm pieces.NOTE 5Forty or more squares will be ob
23、tained depending on the filmthickness. Some laboratories have found that a basket assembly, as shownin Appendix X1, eliminates the need to count the film pieces before andafter the solvent extraction step.9.6 Add the film sample to the hexane making sure allsquares become immersed in the solvent. (U
24、se tweezers.)Replace the kettle head with condenser column. Extract for 2 h.9.7 After the extraction period:9.7.1 Filter the contents of the resin kettle through the frittedporcelain funnel.9.7.2 Transfer the film squares, using tweezers, to a 200-mLBerzelius beaker and recount the film pieces to ve
25、rify that nonewere lost during transfer.9.7.3 Cover the beaker with a watchglass and place it in avacuum oven at 80 6 5C for 2 h.9.7.4 After 2 h, remove the covered beaker from the vacuumoven and place it in a desiccator to cool to room temperature(about 1 h).9.8 Remove the film squares using tweeze
26、rs and weigh themto the nearest 0.1 mg.9.9 Repeat 9.7.3 and 9.7.4 until a constant weight isobtained.10. Calculation10.1 Calculate the weight percent of extractables present inthe original sample as follows:hexane extractables, % 5A 2 B! 3 100 3 0.935A(1)where:A = weight of original sample film, g,B
27、 = weight of the film after extraction, g, and0.935 = correlation factor to eliminate the bias between theoriginal FDA technique and this alternate testmethod.11. Report11.1 Report the hexane extractables to the nearest 0.01 % ascalculated in 10.1.9Ace Glass, Inc., Cat. No. 674006, or its equivalent
28、, has been foundsatisfactory.10VWR Scientific Co., Cat. No. 58947-409, or its equivalent, has been foundsatisfactory.11EM Science, Omnisolv reagent grade, or its equivalent, has been foundsatisfactory.FIG. 1 Resin Kettle SetupD522701212. Precision and Bias1212.1 Hexane Extractable Content of Polyole
29、fins:12.1.1 Table 1 is based on a round robin conducted in 1990in accordance with Practice E 691, involving five materialstested by ten laboratories. The materials were supplied by onelaboratory. Each test result was an individual determination.Each laboratory obtained six test results for each of t
30、he fivematerials. Each laboratory obtained two test results for eachmaterial tested each day for three days.NOTE 6Caution: The following explanations of r and R (12.1.2-12.1.2.3) are only intended to present a meaningful way of considering theapproximate precision of this test method. The data in Ta
31、ble 1 should notbe rigorously applied to acceptance or rejection of material, as those dataare specific to the round robin and may not be representative of other lots,conditions, materials, or laboratories. Users of this test method shouldapply the principles outlined in Practice E 691 to generate d
32、ata specific totheir laboratory and materials, or between specific laboratories. Theprinciples of 12.1.2-12.1.2.3 would then be valid for such data.12.1.2 Concept of r and RIf Sr and SR have beencalculated from a large enough body of data, and for test resultsthat were averages from testing five spe
33、cimens.12.1.2.1 Repeatability Limit, r(Comparing two test re-sults for the same material, obtained by the same operatorusing the same equipment on the same day.) The two testresults should be judged not equivalent if they differ by morethan the r value for that material.12.1.2.2 Reproducibility Limi
34、t, R(Comparing two testresults for the same material, obtained by different operatorsusing different equipment in different laboratories.) The twotest results should be judged not equivalent if they differ bymore than the R value for that material.12.1.2.3 Any judgment in accordance with 12.1.2.1 or
35、12.1.2.2 would have an approximate 95 % (0.95) probability ofbeing correct.12.1.3 BiasThere are no recognized standards by whichto estimate bias of this test method.13. Keywords13.1 ethylene-propylene copolymers; ethylene-vinyl acetatecopolymers; extractables; FDA; hexane; plastics; polyethyl-ene; s
36、olvent extractionAPPENDIX(Nonmandatory Information)X1. BASKET ASSEMBLY FOR n-HEXANE EXTRACTABLESX1.1 If one uses the basket assembly shown in Fig. X1.1,the following steps should be performed after the 2-h hexaneextraction (9.6):X1.1.1 Rinse the basket and contents by immersing severaltimes in fresh
37、 n-hexane contained in a small beaker, allowingthe basket to drain between rinsings.X1.1.2 Remove the excess solvent by briefly blowing thebasket with a stream of nitrogen or dry air.X1.1.3 Place the basket in a vacuum oven for 2 h at 8065C, then cool to ambient temperature in a desiccator (about 1h
38、).X1.1.4 Reweigh the basket and its contents to the nearest0.1 mg.12Supporting data are available from ASTM Headquarters. Request RR: D20-1173.TABLE 1 Hexane Extractable Content of Polyolefins, WeightMaterial Average Sr SR r RHDPE 0.26 0.03 0.05 0.09 0.15LLDPE 0.88 0.11 0.16 0.31 0.46LDPE 1.74 0.08
39、0.15 0.21 0.42EVA 3.54 0.28 0.33 0.78 0.93PP 3.80 0.29 0.35 0.81 0.98D5227013SUMMARY OF CHANGESThis section identifies the location of selected changes to this test method. For the convenience of the user,Committee D20 has highlighted those changes that may impact the use of this test method. This s
40、ection may alsoinclude descriptions of the changes or reasons for the changes, or both.D522701:(1) SI statement added.(2) Practice E 380 was deleted from 2.1.(3) The term “polypropylene” was added editorially to 1.1 and3.2.6.(4) Section 3.1 was changed editorially.(5) Footnote for Terminology E 131
41、was changed editorially.(6) Footnotes 6 through 10, referenced in Section 6, werechanged editorially to reflect the correct catalog numbers.ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this
42、standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years
43、 andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committe
44、e, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-
45、2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).FIG. X1.1 Basket for n-Hexane ExtractablesD5227014
