1、ICS 59.080.30; 83.140.10; 85.060Prfung von Kunststoff-Folien, Elastomerfolien, Papier, Pappe undanderen Flchengebilden; Bestimmung der Wasserdampfdurch-lssigkeit Teil 1: Gravimetrisches VerfahrenIn keeping with current practice in standards published by the International Organization for Standardiza
2、tion(ISO), a comma has been used throughout as the decimal marker.Ref. No. DIN 53122-1 : 2001-08English price group 07 Sales No. 010703.02DEUTSCHE NORM August 200153122-1Continued on pages 2 to 7. No part of this translation may be reproduced without the prior permission ofDIN Deutsches Institut fr
3、Normung e. V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany,has the exclusive right of sale for German Standards (DIN-Normen).Determination of the water vapour transmissionrate of plastic film, rubber sheeting, paper,board and other sheet materials by gravimetryTranslation by DIN-Sprachendienst.
4、In case of doubt, the German-language original should be consulted as the authoritative text.Supersedes DIN 53122-1,November 1974 edition.ForewordThis standard has been prepared by Technical Committee Chemisch- und chemisch technologischePrfverfahren fr Papier, Halbstoff und Chemiezellstoff of the N
5、ormenausschuss Materialprfung (MaterialsTesting Standards Committee).Although the standard is largely based on International Standard ISO 2528 : 1995, it differs from the latterin that a test dish made of glass without a groove around the rim (cf. figure 3) has been specified as anadditional, very w
6、idely used design, which has the advantage that a good seal is ensured since the externalsealing compound (cf. figure 4) hardly ever becomes detached during cooling.Two points are important in selecting the size of dish, namely preventing the desiccant from becomingsaturated during the test, on the
7、one hand, and minimizing the total mass, on the other, to reduce its effecton the accuracy of weighing.Normalization of the water vapour transmission rate to a standard thickness is often required, but is possibleonly for homogeneous material, not for multilayer or laminated samples, and, of course,
8、 only in the case ofan unaltered and essentially uniform material matrix. If these conditions are fulfilled, the water vapourtransmission rate, WVTR, of similar samples of different thickness is inversely proportional to the thickness,i.e.()() 1Thickness2Thickness21orThickness1=WVTRWVTRWVTRTo obtain
9、 guideline values for a laminated material (e.g. multi-layer film) from the WVTR values of thecomponents, if the same (above) conditions are fulfilled, the reciprocals of their water vapour transmissionrates, 1/WVTR, shall be added, i.e. the their water vapour transmission rate of the composite will
10、 then be:()()()1212111-+WVTRWVTRWVTRThis means that, in a laminated material, a layer having a low water vapour transmission rate combined withother highly transmissive layers (i.e. layers having a high water vapour transmission rate) virtually determinesthe rate of the composite on its own.See DIN
11、53122-2 for other methods of determining water vapour transmission rates (e.g. if these are verylow).AmendmentsThis standard differs from the November 1974 edition as follows.a) The scope of the method has been extended to cover water vapour transmission rates from 1 g/m2dto 200 g/m2d.b) The descrip
12、tion of the principle of the method has been amended.c) The specifications for the apparatus and the test procedure have been amended.d) Details of the test report have been changed.e) The standard has been editorially revised.Page 2DIN 53122-1 : 2001-08Previous editionsDIN 53413: 1940x-11; DIN 5312
13、2: 1958-02, 1961-04; DIN 53122-1: 1974-11.All dimensions are in millimetres.1 ScopeThe method specified in this standard serves to determine the water vapour transmission rate, WVTR, of sheetmaterials by the gravimetric method using a dish sealed with wax and can be applied, for example, to plasticf
14、ilm and rubber sheeting, paper, board or textiles with or without coating. It is especially suitable for determiningrates ranging from 1 g/m2d to 200 g/m2d.NOTE: Under refined test conditions (e.g. involving air-pressure control, prolonged test duration and constanttest atmosphere), the method can a
15、lso be used down to rates of about 0,5 g/m2d.2 Normative referencesThis standard incorporates, by dated or undated reference, provisions from other publications. These norma-tive references are cited at the appropriate places in the text, and the titles of the publications are listed below.For dated
16、 references, subsequent amendments to or revisions of any of these publications apply to thisstandard only when incorporated in it by amendment or revision. For undated references, the latest edition ofthe publication referred to applies.DIN 53122-2 Determination of water vapour transmission rate of
17、 plastic film, paper, board and other sheetmaterials by electrolysisDIN 53352 Testing of artificial leather and similar sheet materials Determination of mass per unit areaDIN 53370 Determining plastic film and sheeting thickness by the stylus methodDIN 53504 Determination of tensile stress/strain pr
18、operties of rubberDIN EN 20534 Paper and board Determination of thickness and apparent bulk density or apparent sheetdensity (ISO 534 : 1988)ISO 2528 : 1995 Sheet materials Determination of water vapour transmission rate Gravimetric (dish)methodISO 9932 : 1990 Paper and board Determination of water
19、vapour transmission rate of sheet materials Dynamic sweep and static gas methods3 ConceptWater vapour transmission rateFor the purposes of this standard, the mass of water vapour that passes, under specified conditions, from anevaporation chamber through the exposed surface of a sample into a test d
20、ish per day and per square metreof sample area.NOTE: Since the water vapour transmission rate depends on factors that include the thickness and matrix ofthe sample material, it is not a material constant. Samples having a thickness greater than 3 mm shall betested as specified in ISO 9932. Above tha
21、t thickness and above a water vapour transmission rate of200 g/m2d, the accuracy of measurement decreases.4 DesignationDesignation of the method for determining the water vapour transmission rate by the gravimetric method asspecified in this standard (A):Test DIN 53122 A5 PrincipleA dish (see figure
22、s 2 to 4) filled with desiccant is covered with the sample using wax as sealant and placed inan enclosure (e.g. a desiccator) with a controlled test atmosphere (see note 2 in subclause 7.5). The amount ofwater vapour that passes through the test area of the sample surface and is absorbed by the desi
23、ccant isdetermined by weighing the dish at regular intervals and recording the increase in mass.6 Samples6.1 SamplingSamples shall be taken from the product that are representative of the batch delivered. They shall not exhibitany surface inhomogeneities (e.g. specks) or damage (e.g. creases, holes)
24、 and shall be free of watermarks orimprints, unless the behaviour of, for example, an imprinted film or a folded paper sample is to be tested.Page 3DIN 53122-1 : 2001-086.2 Shape and sizeSamples shall be about 90 mm in diameter.6.3 PreparationThe samples shall be produced, for example, by means of a
25、 template or a punch.If the two surfaces of the sample are not the same, the test area, i.e. the surface that is exposed to the moistatmosphere, shall be specified in the test report. If both surfaces of the sample are to be measured, twice thenumber of samples shall be prepared.If the samples have
26、been prepared using solvents, residues of the latter left in the sample may affect the testresults. Details of any treatment of samples to remove the residual solvent shall be included in the test report.6.4 Number of samplesAt least three samples will be required for every surface to be tested. If
27、the water vapour transmission rate islow, the thickness of the samples is large or the samples are very hygroscopic, one or two additional samplesshall be prepared.7 ApparatusThe following equipment shall be used.7.1 Thickness gauge, as in DIN 53504 for rubber sheeting and rubber-coated textiles, as
28、 in DIN 53370 forplastic/rubber sheets and as in DIN EN 20534 for paper and board.7.2 Balance, capable of weighing to an accuracy of 0,1 mg.7.3 Hygrometer, capable of measuring to an accuracy of 2 % r.h. and having a response sufficient forchecking the maximum time to reach steady-state conditions (
29、cf. subclause 7.5) after the evaporation chamberhas been closed.7.4 Temperature measuring instrument (e.g. a thermometer or electronic instrument), with a limit of errorof 0,5 C.7.5 Evaporation chamber, with a controlled atmosphere (i.e. temperature relative humidity). The time re-quired to re-estab
30、lish the atmosphere after the chamber has been closed should be as short as possible andshould not exceed 1 % of the interval between weighings. If this requirement cannot be satisfied because thesamples have a high water vapour transmission rate, this shall be recorded in the test report.A desiccat
31、or as shown in figure 1, for example, in a controlled-temperature or air-conditioned room may beused as evaporation chamber.NOTE 1: In the case of highly transmissive samples, the number of dishes in the evaporation chamber may bekept low to ensure a constant and uniform distribution of humidity wit
32、hin the tolerances for the test atmos-phere concerned (see subclause 8.2).Page 4DIN 53122-1 : 2001-08Figure 1: Evaporation chamber (without dishes shown in figure 2 or 3)NOTE 2: The relative humidity can be readily established in the desiccator by the solutions containing a largeexcess of salt speci
33、fied in table 1.Page 5DIN 53122-1 : 2001-08Table 1Relative humidity,Salt solution Cas a percentage75 Saturated sodium chloride solution 2585Saturated potassium chloride solution2085 2390Saturated potassium nitrate solution2590 387.6 Test dish, (e.g. dish made of oxidized aluminium sheet about 1 mm t
34、hick (cf. figure 2) or glass dish as infigure 3, whose mass, including desiccant, sample and a light metal lid, shall not exceed 200 g. The internaldepth of the dish should be between 8 mm and 24 mm, but shall preferably be 15 mm. The dish should beshaped so that the test area of the sample is defin
35、ed to an accuracy of 1 % and the sealing compound betweenthe sample and the rim of the dish prevents the penetration of water vapour.Figure 2: Aluminium dishFigure 3: Glass dish7.7 Desiccant, consisting of calcium chloride or silica gel (blue gel), capable of maintaining a relative humidityin the di
36、sh of less than 1 %. The total water absorption of the agent shall not exceed 1,5 g per 25 cm3duringmeasurement.NOTE: It is advantageous to use material with a particle size of 1,5 mm to 2 mm that passes through a 4 mmsieve, has been freed of any fines using a 1,6 mm sieve, and has been dried in the
37、 normal manner.7.8 Sealant, consisting of a wax mixture that adheres strongly to both the dish and the sample, is not brittleat the measuring temperature and is neither hygroscopic nor susceptible to oxidation.The mass of a quantity of wax having a surface area of 50 cm2shall not change by more than
38、 1 mg as a resultof absorbing water at a temperature of 38 C and 90 % relative humidity.Page 6DIN 53122-1 : 2001-08Standard sealants are:a) a mixture containing 80 % (m/m) of paraffin wax melting at temperature of 50 C to 52 C and 20 % (m/m)of polyisobutylene having a fairly low degree of polymeriza
39、tion;b) a mixture containing 60 % (m/m) of a microcrystalline wax and 40 % (m/m) of fully refined crystallineparaffin wax.NOTE 1: It is advantageous to use a light metal lid that covers the dish when it is removed from the testatmosphere and weighed so that the sample releases as little water as pos
40、sible to the surrounding air duringweighing. This, however, is generally unnecessary in the case of non-hygroscopic film or sheets or of thosehaving low water vapour transmission rates.NOTE 2: Cover templates of the type shown in figure 4 facilitate the sealing operation.Figure 4: Details of sealing
41、 samples8 Procedure8.1 Determine the mean thickness from five measurements on each sample. In the case of products havingan outer layer, determine the mass per unit area as described in DIN 53352.8.2 Use one of the following atmospheres in the evaporation chamber:a) atmosphere A: (25 t 1) C and (90
42、t 2) % relative humidity;b) atmosphere B: (38 t 1) C and (90 t 2) % relative humidity;c) atmosphere C: (25 t 1) C and (75 t 2) % relative humidity;d) atmosphere D: (23 t 1) C and (85 t 2) % relative humidity;e) atmosphere E: (20 t 1) C and (85 t 2) % relative humidity.Use atmosphere B for rubber she
43、ets, atmosphere D for plastic film and laminated paper, and atmospheres Dand E for paper and board.8.3 To carry out a series of tests, fill the dried dishes, which have been thoroughly cleaned, with the samemass of the chosen desiccant, ensuring that the latter will be 3 mm to 4 mm below the former.
44、 Then cover thedishes with the samples and firmly seal them to the dish wall, ensuring that the temperature of the sealant (andany annular template used) does not bring about any alteration in the sample.If the wax is spread out on the rims with the aid of a hot spatula, check that the seal is still
45、 intact after the sealanthas cooled.Weigh the dish and sample (and the lid if fitted) to an accuracy of 0,1 mg, then place it in the evaporationchamber and remove the lid.Page 7DIN 53122-1 : 2001-088.4 Carry out weighings preferably at intervals of less than 24 hours, 24 hours, 48 hours, 72 hours an
46、d96 hours, depending on the water vapour transmission rate of the sample, and plot the results as a mass/timecurve until at least three consecutive points lie on a straight line, i.e. the difference between two consecutiveweighings is constant to within 5 % for one and the same interval. Check that
47、the increase in mass betweentwo consecutive weighings is at least 5 mg.8.5 In blank tests, examine samples having low permeation rate and large thickness (e.g. paper laminated withpolymers, plastic film or aluminium foils, cardboard or board, plastics or rubber, and hygroscopic samples) inparallel w
48、ith the blank samples. Make such blank samples in the same way and subject them to the sameconditions, but without desiccant in the dishes.Subtract the blank values from the values measured for the sample dishes having undergone the same treat-ment.9 EvaluationCalculate the water vapour transmission
49、 rate, WVTR, in g/m2d, using the following equation:410.AmWVTRD=(1)whereDm is the difference in mass between the last two consecutive weighings, in g;A is the test area of the sample, in cm2.This equation applies if the interval between consecutive weighings is 24 hours (see subclause 8.4). For othertime intervals:41024AmtWVTRD=(2)wheret is the interval between two weighings used to determine Dm, in hours;Dm is the difference in mass between the last two consecutive weighings, in g;A is the test area of the sample, in cm2.Take the arithmetic mean of