1、Designation: C 771 03Standard Test Method forWeight Loss After Heat Aging of Preformed Tape Sealants1This standard is issued under the fixed designation C 771; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revisi
2、on. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers a laboratory procedure fordetermining the weight loss after heat aging of preformed tapesealants.NOTE 1T
3、est Method C 681 describes a weight loss or volatility testfor knife-grade glazing compounds.1.2 The values stated in acceptable metric units are to beregarded as the standard. The values given in parentheses arefor information only.1.3 The subcommittee with jurisdiction is not aware of anysimilar I
4、SO 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 to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2.
5、Referenced Documents2.1 ASTM Standards:C 681 Test Method for Volatility of Oil- and Resin-Based,Knife-Grade, Channel Glazing Compounds2C 717 Terminology of Building Seals and Sealants2E 145 Specification for Gravity-Convection and Forced-Ventilation Ovens33. Terminology3.1 DefinitionsThe definitions
6、 of the following terms usedin this test method are found in Terminology C 717: preformedtape sealant, sealant.4. Summary of Test Method4.1 The preformed tape sealant to be tested is placed on atared metal plate and weighed. After heat aging, the specimenis weighed again. The difference in weight in
7、dicates thevolatile content of the tape sealant.5. Significance and Use5.1 Preformed tape sealants are tacky, deformable solidsthat are used under compression between two substrates in avariety of sealing applications. Compared to other types ofsealants, that is, gunnable sealants and caulks, sealin
8、g tapes aredesigned to be essentially 100 % solids materials. In use, thesetapes are intended to give long service with minimal weightloss or volatility. This procedure will give a measure of theweight loss of a preformed tape sealant after a controlledperiod of exposure at an elevated temperature.6
9、. Apparatus6.1 Balance, calibrated to weigh specimens to the nearest0.01 g.6.2 Thin Plates of Aluminum or Other Metal, two, not lessthan 51 mm (2 in.) wide by 152 mm (6 in.) long, for each tapeto be tested.6.3 Vented Air Circulating Oven, that complies with Speci-fication E 145 and is capable of agi
10、ng samples at 100 6 2C(212 6 3.6F).7. Sampling7.1 Use a fresh roll of preformed tape sealant for testing.Remove a section of preformed tape sealant approximately 61cm (2 ft) long from the roll and discard.7.2 Remove release paper as required in order to fashion asuitable test specimen.8. Procedure8.
11、1 For each preformed tape sealant to be tested, preparetwo test specimens as follows:8.1.1 Clean and dry two metal plates, weight them, andrecord the tare weight for each to the nearest 0.01 g.8.1.2 Cut the preformed tape sealant into 127-mm (5.0-in.)lengths. Ply strips together to form on each spec
12、imen plate asolid block of preformed tape sealant not less than 38 mm (1.5in.) wide by 3 mm (0.12 in.) thick by 127 mm (5.0 in.) long.8.1.3 Weight the plates with the preformed tape sealant onthem, subtract the tare weights of the plates, and determine andrecord the initial net weight for each test
13、specimen to thenearest 0.01 g.1This test method is under the jurisdiction of ASTM Committee C24 on BuildingSeals and Sealants and is the direct responsibility of Subcommittee C24.20 onGeneral Sealant Standards.Current edition approved May 10, 2003. Published June 2003. Originallyapproved in 1974. La
14、st previous edition approved in 1997 as C 771 97.2Annual Book of ASTM Standards, Vol 04.07.3Annual Book of ASTM Standards, Vol 14.04.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.8.2 Place both specimens in an air circulating oven
15、preset to100 6 2C (212 6 3.6F) and condition them for 1 week at thistemperature.8.3 After conditioning, remove the specimens from the ovenand allow them to cool at room temperature for 1 h.8.4 Reweigh each specimen to the nearest 0.01 g and record.8.5 Subtract the respective tare weights of the plat
16、es fromthe weight of the specimens to determine the net weight of thetape specimen after heat aging, and record these weights to thenearest 0.01 g.9. Calculation9.1 For each specimen, determine the weight loss of thepreformed tape sealant by subtracting the net weight of thepreformed tape sealant af
17、ter heat aging from its initial netweight.9.2 Calculate the percent weight loss for each test specimenby dividing the weight loss by the initial net weight of the tapespecimen times 100.10. Report10.1 Identification of the preformed tape sealant, that is, thename, lot number, and any other identifyi
18、ng characteristics.10.2 Report the average of at least two weight loss calcu-lations for each sample tested.11. Precision and Bias11.1 Interlaboratory round-robin testing of the weight lossof various sealing tapes has determined the 2 s or 95 %confidence level of precision for the preformed tape sea
19、lantweight loss test.11.2 The interlaboratory or multioperator precision for pre-formed tape sealants that show less than 3 % total weight lossis 60.5 %.11.3 The interlaboratory or multioperator precision for pre-formed tape sealants that show greater than 3 % total weightloss is 61.0 %.12. Keywords
20、12.1 preformed tape sealants; tapes; tape sealants; weightloss; weight loss after heat agingASTM 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 determinatio
21、n 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 committee and must be reviewed every five years andif not revised, either reapproved or withdra
22、wn. 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 meeting of theresponsible technical committee, which you may attend. If you feel that your c
23、omments 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, 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).C771032
