1、Designation: D3291 11 (Reapproved 2016)1Standard Practice forCompatibility of Plasticizers in Poly(Vinyl Chloride) PlasticsUnder Compression1This standard is issued under the fixed designation D3291; the number immediately following the designation indicates the year oforiginal adoption or, in the c
2、ase of revision, 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.1NOTEReapproved and editorially changed items throughout in September 2016.1. Scope*1.1 This practice
3、 determines the compatibility of plasticiz-ers in poly(vinyl chloride) plastics by rating the amount ofplasticizer that spews due to compressional stress set up insidea 180 loop bend.NOTE 1Ingredients other than plasticizer can spew from a totalformulation.1.2 The text of this practice references no
4、tes and footnotesthat provide explanatory material. These notes and footnotes(excluding those in tables and figures) shall not be consideredas requirements of this practice.1.3 The values as stated in SI units are to be regarded as thestandard. The values in parentheses are given for informationonly
5、.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 standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.NOTE 2There is
6、 no known ISO equivalent to this standard.2. Referenced Documents2.1 ASTM Standards:2D883 Terminology Relating to PlasticsD1600 Terminology for Abbreviated Terms Relating to Plas-tics3. Terminology3.1 GeneralDefinitions are in accordance with Terminol-ogy D883 and abbreviations with Terminology D160
7、0, unlessotherwise indicated.4. Summary of Practice4.1 Test specimens of plasticized poly(vinyl chloride) sheetare bent through an arc of approximately 180. The innerradius of the bend is equal to the thickness of the specimen.These bent specimens are secured in a jig designed to holdthem in the des
8、ired conformation. At specified intervals oftime, a specimen is removed, bent 360 in the oppositedirection, and the former inside of the loop (now the outside)is examined for evidence of plasticizer spew.5. Significance and Use5.1 It is possible for plasticizers to become less compatiblein poly(viny
9、l chloride) resin when fused compound is sub-jected to compressive stress.5.1.1 This test subjects a standard test specimen to a definitedeformation and allows qualitative determination of theamount of spew that is capable of occurring over a period oftime.5.1.2 An apparent decrease in compatibility
10、 of plasticizerswith subsequent exudation can cause excessive dirt pickup,marring of lacquered or varnished surfaces, sticky feel, and anumber of other associated problems.5.1.3 When a plasticized poly(vinyl chloride) sheet isstressed in compression by bending it through 180, one way torelieve the s
11、tress is by migration of the plasticizer from thecompressed area (inside of bend) to the area in tension (outsideof bend). If these compressive stresses cannot be relievedrapidly by internal migration of plasticizer, then plasticizer willspew. The internal migration of plasticizer will continue andw
12、hen a deficiency of plasticizer occurs at the compressed areaspewed plasticizer will be reabsorbed. It is possible for certainplasticizers to spew and be reabsorbed quite rapidly. Lesscompatible plasticizers are capable of spewing early andcontinuing to spew throughout the test. A test of one weeksd
13、uration is used for screening, while an extended test of sevenweeks duration is used for a complete profile.NOTE 3It is permissible for the seller and the purchaser to agree uponother test conditions of time, temperature, or relative humidity.6. Apparatus6.1 Bending Test Jig, as shown in Fig. 1.1Thi
14、s practice is under the jurisdiction ofASTM Committee D20 on Plastics andis the direct responsibility of Subcommittee D20.15 on Thermoplastic Materials.Current edition approved Sept. 1, 2016. Published September 2016. Originallyapproved in 1974. Last previous edition approved in 2011 as D3291 11. DO
15、I:10.1520/D3291-11R16E01.2For 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 Changes section appear
16、s at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States16.2 Cigarette Papers, cut in half to be approximatelysquare.37. Specimen Preparation7.1 Cut test specimens 12.7 by 25.4 mm (12 by 1 in.) froma plasticized po
17、ly(vinyl chloride) sheet 1.9 6 0.1 mm (0.075 60.005 in.) thick, taking care to ensure the long edges areparallel.NOTE 4Optimum fusion conditions of temperature and time vary withplasticizer and resin type as well as other additives. The processingconditions must be agreed upon by the seller and the
18、purchaser.8. Conditioning8.1 Test specimens shall be conditioned at 23 6 2C (73.46 3.6F) and 50 6 10 % relative humidity for 24 h prior totesting.9. Procedure9.1 Fold the conditioned specimens in half, short endstogether and place the loop end in the jig with the spacer barequal to four times the no
19、minal specimen thickness7.6 mm(0.300 in.)as shown in Fig. 2. Leave about 4.75 mm (316 in.)of the ends outside jig. The loop inside the jig needs to besmooth and continuous and no evidence of cracking is allowedto be seen on the outside of the loop.9.2 Specimens must be thoroughly fused to give meani
20、ngfulresults. Collapse of the loop is one indication of incompletefusion.9.3 Mark the time of starting the test.9.4 Place the loop jig containing the specimens in thechamber at 23 6 2C (73.4 6 3.6F) and 50 6 10 % relativehumidity.9.5 Test individual specimens for 4 h, 24 h, and 7 days.9.6 At the end
21、 of the testing period, remove a specimenfrom the jig and fold the loop in the opposite direction aroundindex finger, so that the inside of the loop in the jig is nowoutside. Examine the loop area for evidence of spew by wipingthe loop area thoroughly with a cigarette paper held around aclean, dry f
22、inger.9.7 Rate spew according to the appearance of the cigarettepaper immediately after wiping.9.8 Subject those specimens that show exudation after the7-day test period to long-term testing by repeating 8.1 9.7.Start seven specimens together with examination of onespecimen each week for 7 weeks.10.
23、 Interpretation of Results10.1 Assign a rating in accordance with the following:Description of Cigarette PaperAmount ofExudationGradingNo mark on paper or visible evidence in loop. none 0Oily mark on paper very faint anddiscontinuous.slight 1It is possible for the wetted area to appearsaturated in s
24、mall spots, although much of itis not saturated.moderate 2Total wetted area is saturated by continuousfilm. Large puddle of plasticizer over entirewetted area.heavy/dripping 33An example of a satisfactory brand is white OCB paper from Reynolds.A Drill and countersink for 6.35-mm (14-in.) flat head m
25、achine screwB Drill and tap to receive 6.35-mm (14-in.) machine screwC Permitted to be any convenient length up to 457 mm (18 in.)MaterialOil-hardening precision ground tool and die steelFIG. 1 Bending Test JigD3291 11 (2016)1211. Report11.1 Report the following information:11.1.1 Description of the
26、 sample, and11.1.2 Ratings for each time period.12. Precision and Bias412.1 ReproducibilityMultilaboratory test results on speci-mens prepared in a single laboratory are reproducible to within61.0 grading unit at two standard deviations when the speci-mens are actually 1 or 2. If specimens are actua
27、lly 0 or 3,practically all tests agreed exactly.12.2 BiasThe bias has not been determined.13. Keywords13.1 plasticizer compatibility; plasticizers; poly(vinyl chlo-ride)SUMMARY OF CHANGESCommittee D20 has identified the location of selected changes to this standard since the last issue(D3291 11) tha
28、t may impact the use of this standard. (September 1, 2016)(1) Added an “s” to “Specimen” in 9.2 to make the sentenceread better.(2) Made editorial corrections throughout the standard.ASTM International takes no position respecting the validity of any patent rights asserted in connection with any ite
29、m mentionedin this standard. Users of this 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 comm
30、ittee and must be reviewed every five years 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 m
31、eeting of theresponsible technical committee, 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
32、, PO Box C700, West Conshohocken, PA 19428-2959,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
33、). Permission rights to photocopy the standard may also be secured from the Copyright Clearance Center, 222Rosewood Drive, Danvers, MA 01923, Tel: (978) 646-2600; http:/ data for this practice are available from ASTM Headquarters.Request RR:D20-1037.FIG. 2 Perspective Drawing Showing Sample Mounted in JigD3291 11 (2016)13
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