ASTM C771-97

NOTICE: This standard has either been superceded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
Designation: C 771 – 97
Standard Test Method for
Weight Loss After Heat Aging of Preformed Tape Sealants
This standard is issued under the fixed designation C 771; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
1. Scope that are used under compression between two substrates in a
variety of sealing applications. Compared to other types of
1.1 This test method covers a laboratory procedure for
sealants, that is, gunnable sealants and caulks, sealing tapes are
determining the weight loss after heat aging of preformed tape
designed to be essentially 100 % solids materials. In use, these
sealants.
tapes are intended to give long service with minimal weight
NOTE 1—Test Method C 681 describes a weight loss or volatility test
loss or volatility. This procedure will give a measure of the
for knife-grade glazing compounds.
weight loss of a preformed tape sealant after a controlled
1.2 The values stated in acceptable metric units are to be
period of exposure at an elevated temperature.
regarded as the standard. The values given in parentheses are
6. Apparatus
for information only.
1.3 This standard does not purport to address all of the
6.1 Balance, calibrated to weigh specimens to the nearest
safety concerns, if any, associated with its use. It is the
0.01 g.
responsibility of the user of this standard to establish appro-
6.2 Thin Plates of Aluminum or Other Metal, two, not less
priate safety and health practices and determine the applica-
than 51 mm (2 in.) wide by 152 mm (6 in.) long, for each tape
bility of regulatory limitations prior to use.
to be tested.
6.3 Vented Air Circulating Oven, that complies with Speci-
2. Referenced Documents
fication E 145 and is capable of aging samples at 100 6 2°C
2.1 ASTM Standards:
(212 6 3.6°F).
C 681 Test Method for Volatility of Oil- and Resin-Based,
7. Sampling
Knife-Grade, Channel Glazing Compounds
C 717 Terminology of Building Seals and Sealants
7.1 Use a fresh roll of preformed tape sealant for testing.
E 145 Specification for Gravity-Convection and Forced-
Remove a section of preformed tape sealant approximately 61
Ventilation Ovens
cm (2 ft) long from the roll and discard.
7.2 Remove release paper as required in order to fashion a
3. Terminology
suitable test specimen.
3.1 Definitions—The definitions of the following terms used
8. Procedure
in this test method are found in Terminology C 717: preformed
tape sealant, sealant.
8.1 For each preformed tape sealant to be tested, prepare
two test specimens as follows:
4. Summary of Test Method
8.1.1 Clean and dry two metal plates, weight them, and
4.1 The preformed tape sealant to be tested is placed on a
record the tare weight for each to the nearest 0.01 g.
tared metal plate and weighed. After heat aging, the specimen
8.1.2 Cut the preformed tape sealant into 127-mm (5.0-in.)
is weighed again. The difference in weight indicates the
lengths. Ply strips together to form on each specimen plate a
volatile content of the tape sealant.
solid block of preformed tape sealant not less than 38 mm (1.5
in.) wide by 3 mm (0.12 in.) thick by 127 mm (5.0 in.) long.
5. Significance and Use
8.1.3 Weight the plates with the preformed tape sealant on
5.1 Preformed tape sealants are tacky, deformable solids
them, subtract the tare weights of the plates, and determine and
record the initial net weight for each test specimen to the
nearest 0.01 g.
This test method
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