1、Designation: D2354 101Standard Test Method forMinimum Film Formation Temperature (MFFT) of EmulsionVehicles1This standard is issued under the fixed designation D2354; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last
2、 revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1NOTEFootnote 2 was corrected editorially in March 2013.1. Scope1.1 This test method covers the determination of the mini-mum temperat
3、ure at which emulsion vehicles coalesce to formcontinuous films. The term “emulsion” in this test methodincludes latex vehicles.1.2 This test method is limited to emulsions having mini-mum film formation temperatures below 90C.1.3 The values stated in inch-pound units are to be regardedas standard.
4、The values given in parentheses are mathematicalconversions to SI units that are provided for information onlyand are not considered standard.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
5、 to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Summary of Test Method2.1 In this test method the minimum film formation tem-perature (MFFT) is determined by visual observation ofcracking or whitening in films that hav
6、e dried over a substratehaving a controlled temperature gradient.3. Significance and Use3.1 The satisfactory film integrity of emulsion coatingsrequires that as the aqueous phase evaporates the resinousportion of the vehicle coalesces into a continuous film. Lowtemperature impairs the fluidity of th
7、e resin particle andthereby their ability to coalesce. Vehicles that can withstandlow temperatures are therefore required, and MFFT is animportant quality feature of emulsion vehicles.4. Apparatus4.1 Minimum Film Formation Temperature BarAn MFFTunit2such as is illustrated in Fig. 1. The bar represen
8、ted in Fig.1 is designed to be used with thermocouples. The thermo-couple leads used with the assembly are iron-constantan withan external resistance of 10 . Also included is a pyrometer(not shown in Fig. 1).NOTE 1Thermometers can be used as an alternative way of measuringtemperature.3It is noted th
9、at larger holes (532 in.) (4 mm) will have to bedrilled in the bar to accommodate the thermometers. If thermometers areselected, all holes are drilled on the same side of the bar, as opposed to thesystem of alternate placement of holes when using thermocouples.NOTE 2Aself-contained unit eliminating
10、the need for any accessories,such as for sub-ambient cooling or temperature measurement, andrequiring only an electrical outlet, piped water, and an air or nitrogensupply has been developed by ICI Paints Division.44.2 Dry Air or Dry Nitrogen Supply, with a regulating valveand flow meter.4.3 Film Cas
11、ter, having a 6-mil (150-m) clearance.5. Reagents and Materials5.1 Dry Ice.5.2 Isopropanol, anhydrous.1This test method is under the jurisdiction of ASTM Committee D01 on Paintand Related Coatings, Materials, and Applications and is the direct responsibility ofSubcommittee D01.33 on Polymers and Res
12、ins.Current edition approved July 1, 2010. Published July 2010. Originally approvedin 1965. Last previous edition approved in 1998 as D2354 98 which waswithdrawn March 2007 and reinstated in July 2010. DOI: 10.1520/D2354-10E01.2The sole source of supply of the MFFT bar, Model CS 188, known to thecom
13、mittee at this time is Dek-Tron Scientific Instrument Corp., 244 East 3rd Street,Plainfield, NJ 07060. If you are aware of alternative suppliers, please provide thisinformation to ASTM International. Your comments will receive careful consider-ation at a meeting of the responsible technical committe
14、e,1which you may attend.3The sole source of supply of the thermometer, Prince No. A-011044 known tothe committee at this time is Princo Instruments Inc., 1020 Industrial Hwy.,Southampton, PA 18966. If you are aware of alternative suppliers, please providethis information to ASTM International. Your
15、comments will receive carefulconsideration at a meeting of the responsible technical committee,1which you mayattend.4The sole source of supply of the MFFTBAR units, Models MFFT-60, andMFFT-90, known to the committee at this time is Rhopoint Instrumentation Ltd.,Beeching Rd., Bexhill-on-Sea, East Sus
16、sex, TN39 3LG, England. For the name ofa local distributor, telephone them at 011441424214291. Interested parties areinvited to submit information regarding the identification of acceptable alternativesto the Committee on Standards, ASTM International. Your comments will receivecareful consideration
17、 at a meeting of the responsible technical committee,1whichyou may attend.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States16. Procedure6.1 Set up the MFFT bar in a level position with the lowertemperature leg of the bar immersed in a d
18、ry ice-isopropanolbath. It is important that the surface of the bar be smooth andplane to ensure uniform film thicknesses. Use a12-gal (2-L)container for this purpose. (The container can be insulated withany suitable material to reduce heat loss.) Adjust the height ofthe dry ice-isopropanol bath as
19、needed to bring the temperatureof the bar to approximately 0C at the lowest temperature-measuring stage of the unit. Lower or higher temperatures canbe obtained, if needed, by adjusting the bath height. The bathheight needed to obtain 0C will vary depending on the heatconductivity of the metal used
20、in the construction of the bar.Expose the higher temperature end of the bar at approximately25C by either conducting the test in a constant-temperatureroom at this temperature or by thermostatting the leg.6.2 Immediately after imposing the temperature gradient onthe bar, place the cover over it and
21、adjust the flow of dry air (ornitrogen) at a rate of 4 L/min from the low-temperature end tothe high-temperature end of the bar. Allowing the air to retainmoisture by warming up prevents water condensation at thecold temperature end that would interfere with film drying.Approximately 45 min is neede
22、d for the temperature gradientto reach equilibrium once the bar is placed in operation. The airmanifold holes must be clean and free of frost before startinga test.NOTE 3A mixture of ethylene glycol and surfactant applied to the airoutlet alleviates the frosting condition temporarily.6.3 Once a cons
23、tant-temperature gradient is established,remove the cover and cast the films using the 3-mil (75 m)applicator (Note 3). Cast films from the low to the high-temperature end of the bar because the extension at thehigh-temperature end is designed to permit overflow to fall intoa container below the bar
24、. After the film is cast and the coverput in place, approximately 1 to 2 h are required for the film todry. Check the air flow and isopropanol bath height before anytests are started and then maintain them at their respectivelevels until the test is completed.NOTE 4If desired, a12-mil (13-m) polyeth
25、ylene terephthalate sheetof 5-in. (125-mm) width can be placed on the bar surface before castingthe film. Tests show that there are no differences between minimumfilming temperatures determined with and without the sheet. The polyeth-ylene terephthalate film permits not only easier clean-up of the a
26、pparatus,but also a semi-permanent record of the test. Special care must beexercised to ensure good contact of the sheet with the bar.Accomplish thisby either of the following techniques:(1) Wipe the sheet with a dry cloth to develop a static charge beforeplacement on the bar.(2) Coat the sheet with
27、 silicone oil before placement on the bar.6.4 After the film has dried, observe for discontinuity asevidenced by whitening or cracking or both. Record the lowesttemperature on the bar at which the film is still continuous asthe minimum film formation temperature.7. Report7.1 Report the following inf
28、ormation:7.1.1 MFFT in degrees Celsius, andNOTE 11 in. = 25.4 mm.FIG. 1 Minimum Film Formation Temperature BarD2354 10127.1.2 Description of the discontinuity indicating degree ofwhitening and cracking.8. Precision and Bias8.1 PrecisionInformation for a formal precision statementhas not yet been obt
29、ained, but it is reported that MFFT valuesobtained by this test method can be expected to fall within62C of their mean.8.2 BiasNo information can be presented on the bias ofthe procedure of this test method, because no material havingan accepted reference value is available.9. Keywords9.1 emulsion v
30、ehicles; film formation; minimum film for-mation temperature; MFFTASTM 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 the validity of any s
31、uch 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. Your comments are invi
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33、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 multiple copies) of thi
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