1、Designation: C 461 81 (Reapproved 2008)Standard Test Methods forMastics and Coatings Used With Thermal Insulation1This standard is issued under the fixed designation C 461; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year o
2、f last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 These test methods cover procedures for sampling andtesting mastics and coatings for use as weather and vaporbarrier
3、 finishes on thermal insulations and for other accessoryuse.1.2 The values stated in inch-pound units are to be regardedas standard. The values given in parentheses are mathematicalconversions to SI units that are provided for information onlyand are not considered standard.1.3 The test methods appe
4、ar in the following order:SectionSampling 4Uniformity and Storage Stability 5Stability Under Freezing 6Density and Weight per Gallon 7Consistency 8Solids Content 9Content of Volatiles and Coverage of Mastics and Coatings 10Build 11Drying Time 12Flash Point 131.4 This standard does not purport to add
5、ress 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.2. Referenced Documents2.1 ASTM Standards:2C 168 Termino
6、logy Relating to Thermal InsulationC 419 Practice for Making and Curing Test Specimens ofMastic Thermal Insulation CoatingsD56 Test Method for Flash Point by Tag Closed Cup TesterD71 Test Method for Relative Density of Solid Pitch andAsphalt (Displacement Method)D93 Test Methods for Flash Point by P
7、ensky-MartensClosed Cup TesterD 140 Practice for Sampling Bituminous MaterialsD 217 Test Methods for Cone Penetration of LubricatingGreaseD 2196 Test Methods for Rheological Properties of Non-Newtonian Materials by Rotational (Brookfield type) Vis-cometerD 3278 Test Methods for Flash Point of Liquid
8、s by SmallScale Closed-Cup Apparatus3. Terminology3.1 DefinitionsFor definitions of terms used in these testmethods, see Terminology C 168.4. Sampling4.1 Prior to opening or sampling, or both, any mastic orcoating, its Material Safety Data Sheet (MSDS) should bereviewed to ensure appropriate precaut
9、ions or personal protec-tive equipment, or both, are utilized.4.2 Take the samples for laboratory examination from theoriginal containers immediately after stirring to a uniformcondition. Determine the number of containers sampled asrequired to represent a shipment in accordance with PracticeD 140.
10、Restir the composite sample immediately before takingout portions for individual tests.5. Uniformity and Storage Stability5.1 Open the original containers and examine them foruniformity of contents. Record the degree of separation, if any,into portions of appreciably different consistency, such as t
11、hickor thin layers, sedimentation or coagulation, etc., also ofdifficulty encountered in stirring to a uniform condition.5.2 Examine the contents of a full container of not less than1 qt (1 L) that has stood undisturbed for 48 h. Make notationof any separation of solvent or water, coagulation, or se
12、ttle-ment of suspended matter, that cannot be overcome by mod-erate agitation.1These test methods are under the jurisdiction of ASTM Committee C16 onThermal Insulation and are the direct responsibility of Subcommittee C16.33 onInsulation Finishes and Moisture.Current edition approved Oct. 1, 2008. P
13、ublished January 2009. Originallyapproved in 1960. Last previous edition approved in 2003 as C 461 81 (2003).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 sta
14、ndards Document Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.5.3 Additionally, if required, examine and report the condi-tion in the container after 3 months storage, examining foruniformity in acco
15、rdance with 5.1.6. Stability Under Freezing6.1 Fill a 1-pt (500-mL) press-top tin can three quarters fullwith the coating, and hold the filled and closed container in achamber at a temperature of 0 6 5F (18 6 3C) for aminimum of 12 h consecutively under natural convectionconditions.6.2 At the expira
16、tion of the freezing period, permit thecoating to warm to room temperature by exposure of thecontainer to the temperature of the laboratory for a minimum of6 h.After the first operation of freezing and thawing, repeat theprocedure twice so that the coating will have been subjected tothree cycles of
17、freezing and thawing.6.3 After the completion of the third cycle, open thecontainer, and note any separation of solvent or water, coagu-lation, settlement of suspended matter, or the presence ofdistinct layers, or a combination of these. If the compoundcannot be rendered homogeneous by moderate stir
18、ring atlaboratory temperature, report that it has coagulated.7. Density and Weight per Gallon7.1 Apparatus:7.1.1 ContainerAny suitable container of known volumemay be used. 7.1.1.1 describes one such container.7.1.1.1 Brass Cylinder, short, about 3 in. (80 mm) high and1.5 in. (40 mm) in diameter, wi
19、th the inside bottom anglesrounded is most convenient. Adjust the capacity of such acylinder to hold 83.3 6 0.1 g of water at 77F (25C).7.2 ProcedureCondition the sample at 77F (25C) andfill the tared container with a slight excess. In filling thecontainer, take precautions to ensure that no air is
20、entrapped,jarring or vibrating the container until no further change involume occurs is satisfactory. Remove excess with a straight-edge flush with the top of the container and wipe the outside ofthe container clean. Then weigh the container and contents towithin 60.5 g.7.3 CalculationsSubtract the
21、weight of the empty con-tainer and divide the remainder by the capacity of the containerin cubic centimetres. The quotient is the density in grams percubic centimetre which, multiplied by 83.3, gives the weightper gallon in pounds.7.3.1 If the cylinder described in 7.1.1.1 is used, the weightof the
22、contents in grams, divided by 10, is the weight per gallonin pounds.8. Consistency8.1 Refer to Test Method D 217 for apparatus and generalprocedure, with exceptions as noted in 8.2-8.4.8.2 In a closed container bring to test temperature sufficientmaterial to overfill the cup of the standard grease w
23、orker. Dothis either in an air bath or water bath, being careful if the latteris used not to permit water to enter the container. Transfer thematerial to the standard cup, occasionally jarring the cupsharply on a hard surface and using a spatula for filling to avoidthe inclusion of air. Scrape off t
24、he excess material extendingabove the rim of the cup by moving the blade of the spatula,held inclined toward the direction of motion at an angle of 45across the rim of the cup.8.3 Determine the cone-penetration reading in accordancewith Section 5 of Test Method D 217, with minimum timebetween fillin
25、g the cup and the reading to avoid temperaturechange of the sample. Report the average of the three tests tothe nearest 0.1 mm as the penetration of the sample.8.4 The practical limit of cone penetration is 375. Ifreadings above this value are obtained, or if specified, analuminum cone and shaft wit
26、h a total weight of 50 g may beused in place of the 150-g cone and shaft specified in TestMethod D 217. If with this modification, readings exceed apenetration of 375, consistency alternatively may be deter-mined by Test Method D 2196. The helipath stand and T-barspindles may be used.9. Solids Conte
27、nt9.1 Weigh about5gofmaterial to the nearest 0.01 g into aweighed flat-bottom metal dish or container (Note 1). Place thedish and its contents in an oven at 105 6 2C (220 6 5F) for2 to 4 h, or until the material shows a loss of not greater than0.02 g on successive hourly weighings; then cool in a de
28、sic-cator and weigh.NOTE 1A friction-top can plug, 50 to 80 mm in diameter, has beenfound convenient.9.2 From the weight of the dried residue and the weight ofthe original sample, calculate the percent nonvolatile matter.10. Content of Volatiles and Coverage of Mastics andCoatings10.1 ScopeThis test
29、 method covers the determination ofthe volume of volatile matter and the coverage per unit of dryfilm thickness of mastics and coatings. The volume of volatilematter is expressed as the percent of the original compound.The coverage is expressed in square feet per gallon of coatingas received per 0.1
30、0 in. (2.5 mm) of dried film thickness. Forsupplementary procedures, refer to Test Method D71 andSection 7 of these test methods.10.2 Test SpecimensTo determine the density of the curedfilm, use two or more test specimen portions at least 1 by 1 in.(25.4 by 25.4 mm) in area and from films of the wet
31、 thicknessspecified by the manufacturer. Prepare and cure these films ondextrin-coated paper as specified in Practice C 419,oroncellophane or other suitable sheet material that can readily beremoved after cure of the mastic or coating at room condition.Cure the film to constant weight at 150F (65C)
32、and the paperremoved before determination of density in accordance withTest Method D71.10.3 CalculationsFrom values for density of the coatingas received (Section 7), and of the cured film, and the weightcontent of solids (Section 9), calculate the volume of volatilematter as follows:V 5 100 2 Sv5 1
33、00 2 SwD1/Ds! (1)where:V = volume of volatile matter, %,Sv= volume of solids, %,C 461 81 (2008)2Sw= weight of solids (Section 9),D1= density of the coating as received, andDs= density of the cured film.10.3.1 Knowing the percent volume of volatile matter, V,calculate the coverage, expressed in squar
34、e feet per gallon ofcoating as received per 0.10 in. (2.5 mm) of dried filmthickness as follows:Coverage 5 16 1 2 V/100!# (2)11. Build11.1 Application of the material to the test panels may be inaccordance with Practice C 419, or to the thickness and by themethod to be followed in practice, such as
35、spray, brush, ortrowel. The compound shall be at 77 6 5F (25 6 3C) unlessotherwise specified such as for hot spray.Apply the material to10 by 10-in. (254 by 254-mm) smooth calcium silicate insu-lation blocks, primed or unprimed in accordance with theinstructions of the manufacturer, at a temperature
36、 of 77 6 5F.Other insulation types may be substituted, and shall be identi-fied in the report. Mask the panel for 1 in. (25.4 mm) along theedges. Immediately after application remove the masking andsuspend the panel in a vertical position in a room at 77 6 5F.After 1 h observe the coating for any fl
37、ow, slippage, andsagging. Record the maximum movement to the nearest132 in.(0.8 mm).12. Drying Time12.1 Test the coated panel prepared in accordance withSection 11 at 15-min intervals to determine the time required toset-to-touch, and at 30-min intervals to determine the time toreach practical hardn
38、ess. The film is considered to haveset-to-touch when a light pressure of the finger shows nomaterial adhering to the finger. Practical hardness is thatcondition when firm pressure of the film between the thumband the finger shows a slight tacky condition, but the film is notruptured and none of the
39、coating adheres to the finger.13. Flash Point13.1 Refer to Method B of Test Methods D93.13.2 Alternatively, refer to Test Method D56.13.3 Alternatively, refer to Test Methods D 3278.14. Precision and Bias14.1 The precision and bias of the procedures detailed inthis standard have not been determined.
40、14.2 The precision and bias of the test methods identifiedherein in otherASTM test methods are as specified in those testmethods.15. Keywords15.1 coatings; consistency; density; mastics; thermalinsulationASTM International takes no position respecting the validity of any patent rights asserted in co
41、nnection 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 responsibility.This standard is subject to revision at any time by the respo
42、nsible 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 ASTM International Headquarters. Your comments will receive careful
43、 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 shown below.This standard is copyrighted by ASTM International,
44、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).C 461 81 (2008)3
