1、Designation: D494 11Standard Test Method forAcetone Extraction of Phenolic Molded or LaminatedProducts1This standard is issued under the fixed designation D494; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revis
2、ion. 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 This test method covers the determination of the amountof acetone-soluble matter in molded or laminated phenolicproducts.1.2 Th
3、e values stated in SI units are to be regarded asstandard. The values given in parentheses are mathematicalconversions to inch-pound units that are provided for informa-tion only and are not considered standard.1.3 This standard does not purport to address all of thesafety problems, if any, associat
4、ed 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.NOTE 1This test method is similar to ISO 308.2. Referenced Documents2.1 ASTM Standards:2D618 Practice fo
5、r Conditioning Plastics for TestingD883 Terminology Relating to PlasticsE11 Specification for Woven Wire Test Sieve Cloth and TestSievesE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method2.2 ISO Standards:ISO 308 PlasticsPhenolic moulding materialsDetermi
6、nation of acetone-soluble matter (apparent resincontent of material in the unmoulded state)3. Terminology3.1 All definitions are in accordance with TerminologyD883.4. Significance and Use4.1 For molded phenolic products, acetone extraction shallbe considered solely as a quantitative expression of a
7、propertynormally associated with degree of cure. There is no demon-strably rigorous relation between the optimum mechanical andelectrical properties of a well-cured piece and the numericalvalue of the acetone test. The amount of acetone-soluble matteris affected by: (1) nature of resin and filler, (
8、2) lubricant, (3)molding temperature, (4) length of cure, (5) thickness of thesection from which sample is taken, (6) nature of molded piece,(7) technique used in molding, (8) distribution of fines in thematerial to be extracted, and (9) method of grinding thespecimen. These variations under some co
9、nditions will cause adifference of 3 to 4 % in acetone-extractable matter. For thisreason, the test method shall be used only as a comparative testfor measuring undercure.4.2 For laminated phenolic products, acetone extractionindicates change in stage of cure, change in resin content,change in type
10、of resin used, presence of plasticizers or otheracetone-extractable addition agents, and is affected in generalby the same factors as stated in 6.15. Apparatus5.1 SievesThe set of sieves used shall consist of sievesNos. 40 (425-m) and 140 (106-m), with a cover andreceiving pan, conforming to the req
11、uirements of SpecificationE11.5.2 Extraction ApparatusThe apparatus may be of thetype shown in Fig. 1, or a Wiley-Richardson type, as shown inFig. 2. The former type is more suitable for use with smallelectric hot plates, while the latter is more suitable for use withoil or water baths. In either ca
12、se, it shall be possible to controlthe temperature so that the rate of extraction can be regulatedaccurately.5.3 Drying DishesThe drying dishes shall be lightweightdishes, approximately 63.5 mm (212 in.) in diameter and 38.1mm (112 in.) in height.1This test method is under the jurisdiction of ASTM C
13、ommittee D20 on Plasticsand is the direct responsibility of Subcommittee D20.70 on Analytical Methods.Current edition approved Sept. 1, 2011. Published September 2011. Originallyapproved in 1946. Last previous edition approved in 2010 as D494 - 04(2010)1.DOI: 10.1520/D0494-11.2For referenced ASTM st
14、andards, 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.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM In
15、ternational, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.6. Preparation of Sample6.1 PrecautionsIt is of utmost importance that extremecare shall be taken during the preparation of the sample forextraction. The sample shall be drillings if possible; however,if
16、 not possible, other suitable means of producing particlesequivalent to drillings shall be used. Drillings taken from alarge molded product shall be truly representative of allsections of the part in proper proportions. The drills forsampling shall be kept sharp and so operated that no undueheating
17、of the material shall occur which will tend to precurethe material.NOTE 2If it is impracticable to obtain samples by drilling, the partsmay be broken up with a lathe, planer, milling machine, or a suitablegrinder. A mortar and pestle or a pebble mill is considered suitable as agrinder, provided no p
18、erceptible heating occurs during the grindingprocedure. A sharp file or rasp may be used for procuring the samplewhere the size or shape of the part is such that no other method is suitable.6.2 In any case, the particles of the sample shall be of thesmallest size practicable, so that they will pass
19、through the No.40 sieve with the minimum of reworking or grinding. It isimportant in preparing the sample that the smallest possiblevolume shall be obtained for a unit weight of the material.6.3 The sample shall be sieved through a No. 40 sieve andthat part which will not pass through shall be regro
20、und andblended with the original material passing the sieve. Afterassembling the Nos. 40 and 140 sieves and the receiving pan,the sample shall be placed in the top sieve, the cover placed on,and the entire sample shall be resieved either by a mechanicalsieve shaker or hand sieving. If the hand-sievi
21、ng method isused, the sieve shall be rotated with slight tapping, the periodof rotation being 5 min.6.4 After sieving, the sample (that portion which has passedthrough the No. 40 sieve and has been retained on the No. 140sieve) shall be placed immediately in an airtight container toprevent absorptio
22、n of moisture by the powder and the conse-quent error in results.7. Conditioning7.1 Condition the test specimens at 23 6 2C (73.4 63.6F) and 50 6 10 % relative humidity for not less than 40 hprior to test in accordance with Procedure A of Practice D618for those tests where conditioning is required.
23、In cases ofdisagreement, the tolerances shall be 1C (1.8F) and 65%relative humidity.7.2 Test ConditionsConduct tests in the standard labora-tory atmosphere of 23 6 2C (73.4 6 3.6F) and 50 6 5%relative humidity, unless otherwise specified in the test meth-ods or in this test method. In cases of disag
24、reements, thetolerances shall be 1C (1.8F) and 62 % relative humidity.8. Procedure8.1 PrecautionsSince the method is capable of exposingthe user to potentially unhealthy fumes of volatile organicchemicals, notably acetone, such exposure shall be kept withinstrict conformity of applicable established
25、 OSHA PermissibleExposure Limits (PEL) and Time Weighted Average (TWA)rules and other available guidance protocols for any of theorganic solvents used. Exposure guidelines should be availableFIG. 1 Extraction ApparatusFIG. 2 Wiley-Richardson Type Extraction ApparatusD494 112in the Material Safety Da
26、ta Sheet, Section 8, Exposure Control/ Personal Protection. Typical safety measures include the useof engineering controls, fully operating and properly adjustedventilation and personal protective equipment, such as hand,eye and breathing protection, along with reliable monitoringand confirmation of
27、 compliance with designated OSHA andother applicable exposure limits.8.2 ExtractionThe extraction procedure shall be carriedout in triplicate. Accurately weigh a 3.000-g portion of thepowdered sample into a tared, acid-hardened open-texturequantitative filter paper, 12.5 to 15 cm in diameter, or int
28、o astandard, single-thickness extraction thimble, 80 by 22 mm,trimmed if necessary. After folding over the thimble or filterpaper containing the sample so that none of the powder canfloat out, place it in a desiccator until ready to insert in thesiphon.8.3 Press the filter paper or thimble containin
29、g the weighedsample into the siphon in such a way that the outlet of thebottom is not plugged. Place the condenser and the siphon inthe extraction tube and add 50 mL of cp acetone. Start thewater through the condenser and adjust the heat (Note 3)sothat the siphon fills and empties between 15 and 20
30、times/h.This rate shall be carefully maintained, and the sample shall beextracted for 4 h. After the siphon empties, remove the flaskand pour the contents into an individually weighed dish. Washthe flask three times with the smallest possible quantity ofacetone, using a wash bottle, and add the wash
31、ings to theextracted liquid in the dish.NOTE 3If an oil or water bath is used for heating, the height of theliquid in the bath should not come above 2.5 cm (1 in.) below the highestlevel of the acetone in the siphon before the siphon starts to discharge.8.4 DryingPlace the dish in a well-ventilated
32、dryingchamber, maintained at 50 6 2C and dry the sample toconstant weight. Between dryings, all dishes containing theresidue shall be kept in a desiccator to prevent the absorptionof moisture.8.5 It is very important that the specified temperature shallbe maintained, otherwise consistent results can
33、not be obtainedbetween different laboratories.NOTE 4An electrically heated oven should not be used unless it isexceedingly well ventilated, as the acetone fumes are likely to come incontact with the heated coils and cause an explosion.9. Calculation9.1 Calculate the percentage of acetone-extractable
34、 matterin the specimen as follows:Acetone2extractable matter, % 5 W 2 D!/S 3 100 (1)where:W = weight of the dish and extract, g,D = weight of the dish, g, andS = weight of original sample, g.10. Report10.1 Report the following information:10.1.1 Percentage of acetone-extractable matter for eachsampl
35、e, and10.1.2 Average percentage of acetone-extractable matter forthe three samples.11. Precision and Bias311.1 Table 1 is based on an interlaboratory study in 1989 inaccordance with Practice E691, involving six materials testedby six laboratories.11.2 Since no absolute method is available for compar
36、ison,no statement of bias can be presented for this test method.12. Keywords12.1 acetone extraction; cure; laminated plastic; moldedplastic; phenolic resin; plasticizers3Supporting data are available from ASTM International Headquarters. RequestRR:D20-1169.D494 113SUMMARY OF CHANGESCommittee D20 has
37、 identified the location of selected changes to this standard since the last issue(D494 - 04(2010)1) that may impact the use of this standard. (September 1, 2011)(1) Revised the relative humidity tolerance in 7.1 to beconsistent with Practice D618.Committee D20 has identified the location of selecte
38、d changes to this standard since the last issue (D494 - 04)that may impact the use of this standard. (July 1, 2010)(1) Added the ISO equivalency statement as Note 1.(2) Removed non-mandatory language in sections 4.1, 5.2,6.1, and 8.1.(3) Changed Section 6.2 to Note 2.(4) Renumbered Notes in text and
39、 renumbered text outline.(5) Changed text immediately following section 8.5 to Note 4.ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of t
40、he 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 andif not revised, either reapproved or withdrawn. Yo
41、ur 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 committee, which you may attend. If you feel that your comment
42、s 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 19428-2959,United States. Individual reprints (single or mul
43、tiple 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). Permission rights to photocopy the standard may also be secured from the ASTM website (www.ast
44、m.org/COPYRIGHT/).TABLE 1 Precision StatisticsValues in the Units of Extracted %Material Average srAsRBrCRDA .3916 .08725 .2244 .24 .63B .5044 .0951 .2220 .27 .62C .5406 .1590 .2223 .45 .62D .5922 .2059 .2361 .58 .66E 4.7628 .2142 1.2449 .60 3.49F 4.6022 .2678 1.1051 .75 3.09Asris the within-laboratory standard deviation of the average.BsRis the between-laboratories standard deviation of the average.Cr =2.8sr.DR =2.8sR.D494 114
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