1、Designation: D 1146 00 (Reapproved 2007)Standard Test Method forBlocking Point of Potentially Adhesive Layers1This standard is issued under the fixed designation D 1146; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of l
2、ast revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.1. Scope1.1 This test method covers the determina
3、tion of the block-ing point of a thermoplastic or a hygroscopic layer or coatingof potentially adhesive material. Potentially adhesive materialscomprise those materials in a substantially nonadhesive statewhich may be activated to an adhesive state by application ofheat or solvents.1.2 The values st
4、ated in SI units are to be regarded as thestandard. The values given in parentheses are for informationonly.1.3 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
5、and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:D 907 Terminology of Adhesives3. Terminology3.1 DefinitionsMany terms in this test method are definedin Terminology D 907.3.2 Definitions of Terms Specific to This S
6、tandard:3.2.1 adhesive blocking, nthe blocking of a potentiallyadhesive face and a standard test paper.3.2.2 blocking, nthe adhesion between touching layers ofsimilar or dissimilar material, such as occurs under moderatepressures during storage or use.3.2.3 cohesive blocking, nthe blocking of two si
7、milar,potentially adhesive faces.3.2.4 critical humidity, nthe lowest humidity at whichblocking of a given degree occurs.3.2.5 critical temperature, nthe lowest temperature atwhich blocking of a given degree occurs.3.2.6 first degree blocking, nan adherence between thesurfaces under test of such deg
8、ree that when the upperspecimen is lifted the lower specimen will cling thereto, butmay be parted with no evidence of damage to either surface.3.2.7 second degree blocking, nan adherence of suchdegree that when the surfaces under tests are parted one surfaceor the other will be found to be damaged.N
9、OTE 1It is permissible to designate such other degrees of blockingas may be agreed upon between the manufacturer and the purchaser of theadhesive.4. Significance and Use4.1 Since some potentially adhesive materials are boththermoplastic and hygroscopic, this test method providesmeans for estimating,
10、 on the same material, both thermoplasticand hygroscopic blocking. Because some requirements aremore strict than others, two varying degrees of blocking arerecognized and defined: (1) First degree blocking, and (2)Second degree blocking. Two types of blocking are covered:(1) Cohesive blocking, and (
11、2) Adhesive blocking.5. Apparatus and Materials5.1 Constant-Temperature Oven, capable of maintainingtemperatures up to 85 6 1C (185 6 2F), and of sufficient sizeto hold one or more desiccators of the type described in 5.2.5.2 Desiccators, for use as humidity chambers, with aminimum diameter of 150 m
12、m (6 in.). The desiccators aremade of glass, with ground flanges and fitting covers. Groundedges are clean and well lubricated with stopcock grease.5.3 Weights, of 0.45 kg (1 lb) each, having a flat base 645mm2(1 in.2) in area.5.4 Glass Plates, of plate glass, measuring 38 by 38 mm(112 by 112 in.).5
13、.5 Standard PaperGeneral usage filter paper cut in by 38by 38-mm (112 by 112-in.) squares.NOTE 2In cases where standard paper is deemed inadequate, adifferent paper, or material other than paper, may be substituted byagreement between the manufacturer and the purchaser of the adhesive.6. Materials6.
14、1 Various Salts, for maintaining constant humidity condi-tions within the desiccators, as follows:6.1.1 Anhydrous calcium chloride (CaCl2), for low humid-ity, and6.1.2 The following salts, employed in saturated solution:1This test method is under the jurisdiction of ASTM Committee D14 onAdhesives an
15、d is the direct responsibility of Subcommittee D14.10 on WorkingProperties.Current edition approved May 1, 2007. Published May 2007. Originallyapproved in 1951. Last previous edition approved in 2000 as D 1146 00.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, P
16、A 19428-2959, United States.SaltApproximate Relative Humidity overSaturated Solution at 38C(100F), %Sodium dichromate (Na2Cr2O72H2O) 50ASodium bromide (NaBr) 54ASodium nitrite (NaNO2)62ASodium acetate (NaC2H3O23H2O) 68ASodium chloride (NaCl) 75APotassium chloride (KCl) 83BAmmonium monophosphate (NH4
17、H2PO4)91AA“Equilibrium Relative Humidities Above Saturated Salt Solutions at VariousTemperaturesReport No. 40 to the American Paper and Pulp Association,”Institute of Paper Chemistry, February 15, 1945.B“International Critical Tables,” Vol 1, 1926, pp. 6768.NOTE 3Desiccators made up with salt soluti
18、ons are prepared and heldat the designated temperatures a sufficient time in advance of use to ensurehumidity equilibrium within the desiccators. An excess of salt is main-tained throughout the period of testing.7. Test Specimens7.1 Cut eighteen test specimens 38 mm (112 in.) squarefrom suitable lar
19、ge specimens for each series of tests (sixspecimens for cohesive tests and three specimens for adhesivetests in both thermoplastic and hygroscopic blocking).7.2 Prepare adhesive specimens to conform closely withpertinent commercial practice in respect to adhesive thickness,backing material, and meth
20、od of preparation.8. Conditioning8.1 Condition test specimens and standard paper for deter-mining thermoplastic blocking in a desiccator over anhydrouscalcium chloride at 38 6 1C (100 6 2F) for 24 h.8.2 Condition test specimens and standard paper for deter-mining hygroscopic blocking at the required
21、 humidity for 24 hat 38 6 1C (100 6 2F).9. Procedure9.1 For cohesive blocking, place two conditioned test speci-mens, adhesive face to adhesive face, on a glass plate. Foradhesive blocking, superimpose three squares of standardpaper on the adhesive face of a conditioned test specimen, andplace on a
22、glass plate.Align the test specimens, standard paper,and glass plate, so that the edges are flush. Place a 0.45-kg(1-lb) weight (5.3) on top of the aligned specimens, in thecenter of the 38-mm (112-in.) square area.9.2 Make triplicate assemblies for each of the followingtypes of test:9.2.1 Cohesive
23、Blocking:(1) Thermoplastic (2) Hygroscopic.9.2.2 Adhesive Blocking:(1) Thermoplastic (2) Hygroscopic.9.3 For thermoplastic blocking, place the above test assem-blies immediately in a desiccator over anhydrous calciumchloride at 38 6 1C (100 6 2F) for 24 h. For hygroscopicblocking, place the test ass
24、emblies immediately in a desiccatorat approximately 50 % relative humidity and at 38 6 1C for24 h.9.4 Remove the test assemblies, allow to cool to roomtemperature, and examine promptly, noting the degree ofadherence. Classify the degree of blocking as follows: (1) Free,(2) First degree blocking, (3)
25、 Second degree blocking, or (4)Any other degrees of blocking agreed upon.9.5 If the classification is “free,” repeat the test with newspecimens at successively higher temperatures (in incrementsof 5C (10F) for thermoplastic blocking, or successivelyhigher humidities (in increments shown with various
26、 salts) forhygroscopic blocking, until first or second or other degreeblocking is found, or until a suitably high temperature orhumidity is reached.10. Report10.1 Report the following information:10.1.1 Complete identification of the adhesive tested, in-cluding thickness or weight per unit area, and
27、 method ofapplication to supporting carrier, if any,10.1.2 Any alternative material employed in 5.5,10.1.3 Type of test usedwhether for cohesive or adhesiveblocking, thermoplastic or hygroscopic blocking,10.1.4 Degree of blockingfree, first degree, second de-gree, or other,10.1.5 Results of all dete
28、rminations made, including: forthermoplastic blocking, the critical temperature or (alterna-tively) the highest temperature employed; for hygroscopicblocking, the critical humidity or (alternatively) the highesthumidity employed; any other critical phenomena.11. Precision and Bias11.1 No information
29、 is presented about either the precisionor bias of Test Method D 1146 for measuring the blockingpoint since the test result is nonquantitative.12. Keywords12.1 adhesive blocking; blocking; blocking point; cohesiveblocking; first degree blocking; second degree blockingASTM International takes no posi
30、tion 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 the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibili
31、ty.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. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to AST
32、M International Headquarters. Your comments will receive careful consideration at a meeting 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
33、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 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).D 1146 00 (2007)2
