ASTM D4446-08(2012)
(Test Method)Standard Test Method for Anti-Swelling Effectiveness of Water-Repellent Formulations and Differential Swelling of Untreated Wood When Exposed to Liquid Water Environments
Standard Test Method for Anti-Swelling Effectiveness of Water-Repellent Formulations and Differential Swelling of Untreated Wood When Exposed to Liquid Water Environments
SIGNIFICANCE AND USE
3.1 This test method is useful in determining the relative anti-swelling efficiency of various water-repellent formulations when applied to wood. It is the initial means of estimating the ability of water-repellent treated wood to perform satisfactorily when exposed to liquid water environments.
3.2 The swelling differences of untreated wood species when subjected to water immersion can also be determined by this test method.
3.3 This method is a basic screening test and thus provides an initial determination of the anti-swelling efficiency of water repellents. It is a qualitative method designed to provide a reproducible means of establishing: (1) the anti-swelling efficiency of water-repellent formulations, and (2) the relative swelling of untreated wood species when both are exposed to liquid water environments.
SCOPE
1.1 This test method is designed to evaluate the effectiveness of water-repellent compositions for retarding dimensional changes in coated wood submerged in water. It can also be used to measure the differential swelling of untreated wood when exposed to liquid water environments. The compositions tested are designed to be mixed until uniform and applied by brush, roller, dip or spray to an exterior wood surface.
1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
General Information
Relations
Standards Content (Sample)
NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: D4446 − 08(Reapproved 2012)
Standard Test Method for
Anti-Swelling Effectiveness of Water-Repellent Formulations
and Differential Swelling of Untreated Wood When Exposed
to Liquid Water Environments
This standard is issued under the fixed designation D4446; 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 (´) indicates an editorial change since the last revision or reapproval.
1. Scope when applied to wood. It is the initial means of estimating the
ability of water-repellent treated wood to perform satisfactorily
1.1 This test method is designed to evaluate the effective-
when exposed to liquid water environments.
ness of water-repellent compositions for retarding dimensional
changesincoatedwoodsubmergedinwater.Itcanalsobeused 3.2 The swelling differences of untreated wood species
to measure the differential swelling of untreated wood when when subjected to water immersion can also be determined by
exposed to liquid water environments.The compositions tested this test method.
are designed to be mixed until uniform and applied by brush,
3.3 This method is a basic screening test and thus provides
roller, dip or spray to an exterior wood surface.
an initial determination of the anti-swelling efficiency of water
1.2 The values stated in SI units are to be regarded as the repellents. It is a qualitative method designed to provide a
standard. The values given in parentheses are for information reproducible means of establishing: (1) the anti-swelling effi-
only. ciency of water-repellent formulations, and (2) the relative
swelling of untreated wood species when both are exposed to
1.3 This standard does not purport to address all of the
liquid water environments.
safety concerns, if any, associated with its use. It is the
responsibility of the user of this standard to establish appro-
4. Apparatus
priate safety and health practices and determine the applica-
4.1 Conditioning Room or Chamber, having a controlled
bility of regulatory limitations prior to use.
temperature of 23 6 2°C (73.5 6 3.5°F), and a controlled
2. Summary of Method relative humidity of 50 6 5 %. This room is used to establish
a uniform moisture content in the test specimens. In all studies
2.1 Wood samples in the form of elongated slats that
the temperature and relative humidity selected by the investi-
represent the timber species or product/treatment combination
gator must be stated and must remain constant throughout a
to be evaluated are exposed in soak containers. The elongated
given conditioning and test period.
slats are immersed in the water-repellent formulation, condi-
4.2 Balance, sensitive to at least 0.01 g.
tioned with appropriate weighing, then subjected to immersion
in distilled water for a prescribed period. The untreated slats
4.3 Treating Tank (Fig. 1).
omit the immersion in the water-repellent formulation. The
4.4 Swellometer, as illustrated in Fig. 2, Fig. 3, and Fig. 4.
swelling resulting from immersion for the selected time period
is determined by reading a dial gage calibrated in increments of
5. Test Specimens
0.025 mm (0.001 in.).
5.1 Wood used for these tests must be straight-grained,
2.2 A water repellent efficiency of 60 % is required to pass
flat-sawn, clear, kiln-dried Ponderosa pine sapwood or other
this test.
suitable species. Cut the parent boards in a manner to give
1 1
specimens 6 mm ( ⁄4 in.) in the longitudinal dimension, 1 ⁄2 in.
3. Significance and Use
(38 mm) in the radial dimension, and 254 mm (10 in.) in the
3.1 This test method is useful in determining the relative
tangential dimension. Cut with a sharp, fine-toothed saw to
anti-swelling efficiency of various water-repellent formulations
obtain as smooth a surface as possible without sanding.
Number each specimen for identification and reference.
5.1.1 Selection of Ponderosa pine sapwood can be assured
This test method is under the jurisdiction of ASTM Committee D01 on Paint
and Related Coatings, Materials, andApplications and is the direct responsibility of
by the following quick chemical test: (1) prepare a solution of
Subcommittee D01.42 on Architectural Coatings.
5 g of benzidine in 25 g of hydrochloric acid and 970 g of
Current edition approved July 1, 2012. Published August 2012. Originally
water, and (2) prepare a second solution consisting of a 10 %
approved in 1995. Last previous edition approved in 2008 as D4446 – 08. DOI:
10.1520/D4446-08R12. concentration of sodium nitrite in water. When the test is to be
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D4446 − 08 (2012)
FIG. 1 Treating Tank—Five Samples Tested Simultaneously
FIG. 2 Single Test Swellometer Tank and One Sample
FIG. 3 Single Test Swellometer Tank—With One Sample In Place
6. Formulations
6.1 Treat the test specimens with the ready-to-use formula-
made, pour equal amounts of the two solutions together and
tion as advocated by the manufacturer of the formulation.
then apply to the wood surface by means of brushing or
dipping. The sapwood immediately shows a yellowish color, 6.2 Test,experimentalorcontrolformulationsmaybeadded
while the heartwood turns dark red-brown. The colors remain to the test as desired.
distinct after drying.
6.3 Establish adequate records, reference samples and iden-
5.2 Determine the swelling of an untreated specimen from tification to permit independent review and analysis.
each parent board before testing begins. Do this by equilibrat-
7. Test Procedure
ing the specimen in accordance with 7.1 and then testing in
accordance with 7.5.1. The swelling shall not be less than 8.25 7.1 Cut two adjacent specimens, both either tangentially or
mm (0.325 in.). See Table 1. longitudinally, from each board. Specimen pairs from ten
D4446 − 08 (2012)
FIG. 4 Swellometer
A
TABLE 1 Natural Tangential Swelling of Selected Species
7.3.2 Fully immerse in the Treating Tank (Fig. 1) five of the
Tangential
ten test specimens (one from each board) in the formulation to
Species Swelling,
be tested. The immersion time for solvent-based formulations
%
shall be 30 s. Because of the small size of the specimens (6 mm
Pine, ponderosa 6.2
( ⁄4 in.) thick) a 30-s immersion period is adequate for
southern yellow 7.5
Oak, red 9.5
formulation pickup. This 30-s immersion period will reflect
white 10.5
appropriate screening test results, but is not intended to reflect
Maple 8.3
the proper treatment time for use on commercial products. The
Beech 11.9
Douglas-fir 7.6
immersion time for water-based formulations shall be 3 min.
A
Source: “Wood Handbook,” Agriculture Handbook No. 72, USDA, Forest Ser-
Treat the test specimens while in the conditioning room/
vice, Washington, DC, 1974.
chamber or within 30 s after removal from the conditioning
room/chamber. Five untreated specimens, one from each of the
boards, serve as controls.
7.3.3 Place both the five treated and the five untreated
specimens separately on a raised screen or other suitable rack
different boards (20 test specimens in all) make a set (in
tha
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.