1、Designation: F 1349 98 (Reapproved 2003)Standard Test Method forNonvolatile Ultraviolet (UV) Absorbing Extractables fromMicrowave Susceptors1This standard is issued under the fixed designation F 1349; the number immediately following the designation indicates the year oforiginal adoption or, in the
2、case of revision, 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.1. Scope1.1 This test method covers the determination of relativelypolar ultraviolet (UV) absorbing
3、 components that may migratefrom microwave susceptor packaging into food simulants, suchas corn oil and Miglyol 812.21.2 This test method has been collaboratively studied usingbilaminate susceptors constructed of paperboard, adhesive, anda layer of polyethylene terephthalate polymer (PETE) suscep-to
4、r. Adhesive and PETE related compounds were quantitatedusing this test method.1.3 The values stated in SI units are to be regarded as thestandard.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 stan
5、dard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use. Specific warningstatements are given in 4.3.2.3.2. Referenced Documents2.1 ASTM Standards:3F 874 Test Method for Temperature Measurement and Pro-filing for Microwave Su
6、sceptorsF 1317 Test Method for Calibration of Microwave Ovens3. Apparatus and Reagents3.1 Microwave Oven, 700 6 35 W, calibrated. Refer to TestMethod F 1317.3.2 High-Pressure Liquid Chromatograph (HPLC), consist-ing of:3.2.1 Pump, capable of 1.5 mL/min with flow precision62%.3.2.2 Injector, loop-typ
7、e, equipped with 20-L loop.3.2.3 Guard Column,C8, 5 m.3.2.4 Analytical Column,C8, 5 m, 250 by 4.6 mm.3.2.5 Detector-UV Absorbance, set for 254 nm. Adjustsensitivity to give a 70 to 100 % of full scale peak for the 5-ppm dimethylterephthalate DMT standard.3.2.6 Gradient Program, 4 to 60 % Mobile Phas
8、e B in 8min; 60 to 70 % B in 9 min; 70 to 100 % B in 7 min; 100 % Bfor 11 min; 100 to 4 % B in 5 min; 4 % B for minimum of 5min. Where Mobile Phase A ( v/v) is 85 + 15 + 0.25 %water:acetonitrile:acetic acid, and Mobile Phase B (v/v)is15 + 85 % water:acetonitrile.3.2.7 Peak Area Integration SystemIni
9、tialize data acqui-sition or integration system, or both, from 5 to 35 min duringthe separation.3.3 Hexane, LC/UV grade.3.4 Acetonitrile, LC/UV grade.3.5 Corn OilObtain corn oil that is as pure and fresh aspossible to minimize peaks in nonvolatiles extractables chro-matogram. Alternatively, Miglyol
10、812 (a fractionated coconutoil) or synthetic fat simulant HB 3074can be used as asubstitute for corn oil.3.6 Dimethylacetamide (DMAC), LC/UV grade.3.7 Conical Bottom Test Tubes, 50 mL, graduated.3.8 Bishydroxyethyleneterephthalate (BHET).53.9 Diethylterephthalate (DET).63.10 Dimethylterephthalate (D
11、MT).73.11 Fluoroptic Thermometry System.83.12 Temperature Probes, four, high temperature93.13 Glass Beads, 3 to 4 mm, clean thoroughly by rinsingwith methylene chloride followed by soaking for 30 min inacetonitrile. Dry thoroughly before using.3.14 Recommended Microwave Nonvolatile ExtractionCellWal
12、dorf Polytetrafluoroethylene cell.10(See Figs. 1-3).1This test method is under the jurisdiction of ASTM Committee F02 on FlexibleBarrier Materials and is the direct responsibility of Subcommittee F02.15 onChemical/Safety Properties.Current edition approved Oct. 10, 1998. Published January 1999. Orig
13、inallypublished as F 1349 91. Last previous edition F 1349 94.2Miglyol 812 is a product of Dynamit Nobel Chemicals, available from HULSAmerica, Inc., 80 Centennial Ave., PO Box 456, Piscataway, NJ 08855-0456.3Annual Book of ASTM Standards, Vol 15.09.4Fat simulant HB 307 is available from NATEC, Behr
14、ingstrabe 154, Postfach501568, 2000 Hamburg 50, West Germany.5Available from Polysciences, Inc., 400 Valley Rd., Warrington, PA 18976.Request Catalog Number 18218.6Available from Fisher Scientific, 711 Forbes Ave., Pittsburgh, PA 15219.Request Catalog Number 1189984.7Available from Aldrich, 1001 W.
15、St. Paul Ave., Milwaukee, WI 53233. RequestCatalog Number 18512-4.8Luxtron Model 750, or equivalent, has been found suitable for this purpose.Available from Luxtron Co., 1060 Terra Bella Ave., Mountain View, CA 94043.9Luxtron Model MIW, or equivalent, has been found suitable for this purpose.10This
16、and additional PTFE polymer materials are available from Read Plastics,12331 Wilkins Ave., Rockville, MD 20852.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.This cell must be constructed by a machine shop experiencedin working with
17、 polytetrafluoroethylene (PTFE). After micro-waving oil in the cell, the cell should be rinsed with methylenechloride to remove residual oil and prevent carry-over.3.15 Solvent Concentration ApparatusKuderna-Danishevaporative concentrator, rotory evaporator; or Zymark Tur-boVap11at a nitrogen pressu
18、re of 30 psi and a water bathtemperature of 50C.4. Procedure4.1 Temperature Measurement:4.1.1 Refer to Test Method F 874 to determine the time andwater load specifications.4.2 Sample Preparation and Microwave Heating:NOTE 1Always be sure the microwave oven is at ambient temperaturebefore starting an
19、y temperature measurement or heating procedure toensure consistency of output. Cooling of the microwave oven can beexpedited by using ice in beakers or crystallization dishes or by using coldpacks such as “blue ice.”4.2.1 Select a representative piece of the susceptor sampleto be tested. If the susc
20、eptor is part of a package, trim excessmaterial from around susceptor. Determine the area of theactive susceptor material. The susceptor should be cut to fit intoa Waldorf PTFE Cell10with the screw seal ring firmly seatedagainst the susceptor surface. Use of the Waldorf PTFE cellreduces the risk of
21、spilling hot oil and in addition, gives areproducible surface area (53.5 cm2) for extraction. Alterna-tively, cut a 13 by 18-cm rectangular piece of the activesusceptor material, form an extraction boat with sides 1.5 cmhigh (boat configuration = 1.5 by 10 by 15 cm, approximately150 cm2of surface ar
22、ea). Staple the corners of the boatsecurely.4.2.2 Add 53.2 g of Miglyol 812 of corn oil to the WaldorfPTFE Cell.10Alternatively, add 22.5 g oil and 75 g of glassbeads to the extraction boat.4.2.3 Measure the mass of the room-temperature distilledwater load as determined in 4.1.1 into a 600-mL beaker
23、 andadd a boiling chip to this beaker.4.2.4 Place Waldorf PTFE Cell10or extraction boat contain-ing the oil in the center of the microwave oven. Alwaysposition cell/extraction boat in the same position for subse-quent runs.4.2.5 Insert the temperature sensing probes through pre-formed holes in the w
24、alls in Waldorf PTFE Cells10(shown inFig. 1 and in the lower center sketch of Fig. 2), or in the caseof the extraction boat, tape the probe to the wall of the ovensuch that the probe tip maintains contact with the extractionboat. Manipulate the probes until they make good firm contactwith the active
25、 face of the susceptor material.4.2.6 Microwave the cell or alternate extraction boat usingthe time specifications as determined in Test Method F 874.Record the probe temperatures, preferably at 5-s intervals, butat intervals not to exceed 15 s.4.3 Quantitative Analysis:4.3.1 Standard Curve:4.3.1.1
26、Prepare a standard mixture of 10 ppm ( w/v) each ofBHET, DMT, DET, and any other identified UV components11Zymark Turbo Vap is a product of the Zymark Corp., Zymark Ctr., Hopkinton,MA 01748.NOTE 1The116-in. (1.6-mm) diameter hole is for a Luxtron MIWtemperature sensing probe. Number of holes and loc
27、ation may vary byapplication.FIG. 1 Collar Section of Waldorf PolytetrafluoroethyleneMicrowave Nonvolatile Extraction Cell11NOTE 1Relieve thread at bottom. Collar must seal to bottom of cap.FIG. 2 Cap Section of Waldorf Polytetrafluorethylene NonvolatileExtraction CellF 1349 98 (2003)2(see appendix)
28、 of the susceptor in DMAC. Proceed to generatechromatograms using high pressure liquid chromatography inaccordance with 3.2.5, 3.2.6, and 4.3.2.8. Retention times forBHET, DMT, and DET will be approximately 7.6, 16.6, and21.5 min respectively.4.3.1.2 Repeat with a standard of 5 ppm of DMT.4.3.1.3 Re
29、peat with a standard of 1 ppm of DMT.4.3.1.4 Construct a plot of area response of DMT versusconcentration.4.3.1.5 For quantitation of PETE oligomers use the follow-ing response factor to construct an area response plot;( mass/area)DMT/(mass/area)Trimer= 0.912.4.3.2 Quantification of Extractables fro
30、m Susceptor:4.3.2.1 Prepare and place the sample in the microwave ovenin accordance with 4.2.1-4.2.6.4.3.2.2 Microwave at full power using the time determinedin 4.1.1.4.3.2.3 Stir oil in boat or cell. WarningBe extremelycareful when handling the Waldorf PTFE cell10or extractionboat. Use protective g
31、loves. Severe burns can result fromextremely hot oil.4.3.2.4 Weigh 3 6 0.03 g of stirred oil into a 50-mL beaker.Add 25 mL of hexane, stir, and transfer to a 125-mL separatoryfunnel.4.3.2.5 Rinse the beaker with an additional 25-mL portionof hexane and add to the separatory funnel. Rinse the beakerw
32、ith 25 mL of acetonitrile and add to the separatory funnel.Shake the separatory funnel and draw off the acetonitrile phaseinto a 50-mL conical test tube or into a Kuderna-Danishevaporative concentrator with a 10-mL receiver or othersolvent concentration apparatus. Rinse the beaker with asecond 25-mL
33、 portion of acetonitrile, add to the separatoryfunnel, shake, draw off acetonitrile, and add to the previousacetonitrile extract.4.3.2.6 Concentrate the combined acetonitrile extracts to 0.4to 0.5 mL in a 65C water bath under a gentle stream ofnitrogen or using a Turbo Vap11or on a steam bath in aKu
34、derna-Danish evaporative concentrator with a 10-mL re-ceiver and three-ball Snyder column.4.3.2.7 Cool, take residue in test tube to 2 mL with DMAC.4.3.2.8 Inject onto HPLC system, with or without filteringas desired, and separate using gradient conditions defined inapparatus in 3.2.6. Dilute sample
35、 if necessary if any extractantpeaks are excessively large.4.3.2.9 To determine a Miglyol 812 or corn oil or blank,place the proper amount of oil in a borosilicate petri dish. Placea fresh susceptor in the oven, place the petri dish on thesusceptor and proceed through 4.3.2.1-4.3.2.8.4.3.2.10 For re
36、ference, various oligomers of polyethyleneterephthalate (PETE) will have the following retention timesrelative to DET:cyclic trimer = 2.8tetramer = 5.2pentamer = 6.8hexamer = 7.8heptamer = 8.8octamer = 9.8nonamer = 10.2FIG. 3 Suggested Modifications to Waldorf CellF 1349 98 (2003)34.3.2.11 Subtract
37、blank oil peak contributions from thesample chromatograms. Sum all the remaining peak areas inthe sample chromatogram.4.3.2.12 Using the area versus concentration plot for DMT,find the quantity of extractables present in the concentratedcorn oil extract (QA ppm).5. Calculation5.1 Calculate susceptor
38、 extractables as follows:g/in.2! 5 6.4516*QA*TO/OS!*V! / A (1)where:QA = quantity of component in oil extract, ppm,TO = total mass of oil in cell (53.5 g),OS = mass of oil sampled from boat or cell (3.00 g),V = final volume of concentrated extract, mL (2.0mL),A = surface area extracted, cm2(150 cm2f
39、or boat).For the Waldorf Cell10area circleA = 0.25*p*d2(53.52 cm2), and6.4516 =cm2/in.26. Report6.1 Report the following information:6.1.1 A representative sample chromatogram.6.1.2 The name and concentration in micrograms per squareinch of the individual migrants found in the oil. Include thedata f
40、or each sample analyzed and all replicate samples.6.1.3 A representative sample time-temperature profile.7. Precision and Bias7.1 Precision:7.1.1 Two different microwave susceptor samples were usedin two separate collaborative studies. Both susceptors werelaminates of PETE-adhesive-paperboard.7.1.2
41、Six laboratories participated in the first study. Allsusceptor samples were prepared as extraction boats (1.5 by 10by 15 cm) containing 22.5 g of corn oil and 75 g of glass beads.All susceptor samples were heated for a fixed time (5.0 min)using a fixed water load (250 g) in the microwave oven. Table
42、1 lists the means and standard deviations for the determinationof PETE cyclic oligomers that migrated to corn oil. Table 2lists the values for the coefficients of variation of this testmethod for PETE oligomers based on the collaboration oflaboratories (1989) reporting triplicate analyses.7.1.3 In 1
43、992, six laboratories participated in a secondstudy. All susceptor samples were evaluated using the WaldorfPTFE cell.10Susceptor samples were heated for 2 and 5 minusing a fixed water load (100 g). After concentrating, theextracts were analyzed for total PETE oligomers and diethyl-ene glycol dibenzo
44、ate (DEGDB) using HPLC with UV detec-tion.All analyses were performed in duplicate. Table 3 lists theintralaboratory RSDrand interlaboratory RSDRfor total PETEoligomers and DEGDB determined in this study.7.1.4 The two studies had significant differences (differentsusceptor constructions, different w
45、ater loads, and differentmicrowave heating times) and cannot be considered replicateinvestigations. Of the data obtained from the two studies, onlythe total PETE oligomers determined after 5 min microwaveheating can be compared and are in reasonable agreement.7.2 BiasSince no absolute method is avai
46、lable for com-parison, no statement can be presented for this test method.8. Keywords8.1 extraction cell, Waldorf; extractables, microwave sus-ceptors; extractables, nonvolatile by HPLC; extractables, non-volatile UV absorbing; fat simulant, corn oil; fat simulant,Myglyol; fluoroptic thermometry; mi
47、crowave susceptors;Myglyol; migration; nonvolatile extractables; nonvolatile ex-tractables, quantitation of, by HPLC; PETE; susceptors, mi-crowave, PETETABLE 1 Determination and Deviations for PETE Oligomers ThatMigrated to Corn OilMean, mg/in.2Standard Deviation, mg/in.2Cyclic trimer 0.148 0.023Cyc
48、lic tetramer 0.021 0.006Cyclic pentamer 0.012 0.004Total oligomers 0.197 0.031F 1349 98 (2003)4APPENDIX(Nonmandatory Information)X1. RECOMMENDED PRACTICEX1.1 Initially the total UV absorbing components presentin the polymer, adhesive, and paperboard should be deter-mined. This may be accomplished by
49、 shredding two 8 by 10-in.(20 by 25.4-cm), or equivalent, surface area susceptor sheetsand placing the shreds in a Soxhlet extractor. This shreddedsusceptor is then serially Soxhlet extracted with hexane,chloroform, and acetonitrile (or similar solvents that will notdissolve the polymer) for 3 h each. After each 3-h interval, thesolvent is gently evaporated until a few millilitres of residualsolvent remain, before the addition of the next solvent. Afterthe third solvent extraction, the solvent is concentrated andprepared for HPLC analysis using UV detection. Th
