ASTM E2407-04(2009)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
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Designation: E2407 − 04(Reapproved 2009)
Standard Test Method for
Effectiveness of Defoaming Agents
This standard is issued under the fixed designation E2407; 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 4. Summary of Test Method
1.1 This test method describes a qualitative method for the 4.1 Foam is generated in a high-speed blender with a dilute
evaluation of liquid defoaming agents used to control undesir- surfactantsolutionpriortoadditionofadefoamingagenttothe
able foam in dilute, aqueous surfactant solutions. This labora- blender cup. After 1 min of gentle agitation and five min of
tory test method may be applied to aqueous systems containing rest, any remaining foam is measured. The ability of the
additional components, such as agricultural chemicals. This defoaming agent to reduce foam is expressed as percent foam
method is described using SI units reduction.
1.2 The values stated in SI units are to be regarded as
5. Significance and Use
standard. No other units of measurement are included in this
5.1 This test is designed to determine the ability of a
standard.
material to reduce or eliminate undesirable foam that can be
1.3 This standard method does not purport to address all of
generated during the mixing and application of agricultural
the safety problems, if any, associated with its use. It is the
chemicals in dilute aqueous mixtures.
responsibility of the user of this standard to establish appro-
5.2 This method is useful for testing liquid defoaming
priate safety and health practices and determine the applica-
agents, such as “silicone emulsion” or “organic” type defoam-
bility of regulatory limitations prior to use.
ing agents. In principle, it might also be used to test dry
antifoam agents with minor modifications to the procedure.
2. Referenced Documents
5.3 This method could be employed to determine the
2.1 ASTM Standards:
relative effectiveness of one defoaming agent versus another. It
E1116 Test Method for Emulsification Characteristics of
is left to the user of this method to interpret the results with
Pesticide Emulsifiable Concentrates
respect to the actual field use of the defoaming agents tested.
E1519 Terminology Relating to Agricultural Tank Mix Ad-
juvants
5.4 This method assumes that the defoaming agent being
tested has sufficient durability to maintain its activity for the
3. Terminology
duration of the test.
3.1 Definitions:
5.5 Sodium lauryl ether sulfate as the foaming agent is
3.1.1 defoaming agent, n—a material that eliminates or
described in Section 7, Reagents. If desired the user of this test
suppresses foam in the spray tank. E1519
method may select an alternative suitable foaming agent.
3.1.2 durability, adj—the degree to which a defoaming
6. Apparatus
agent remains effective over time under foam generating
conditions 6.1 Blender—Theblendershouldhavearemovable1.2liter
glass cup equipped with a removable stainless steel blade
3.1.3 foaming agent, n—a material that increases the vol-
assembly (Note 1), and a motor base capable of a no-load
ume or stability of the foam formed in a spray mixture
speed of 22 000 rpm.
NOTE 1—The blade assembly should turn freely by hand. If it does not,
1 replace the assembly before using this test method.
This test method is under the jurisdiction of ASTM Committee E35 on
Pesticides and Alternative Control Agentsand is the direct responsibility of Sub-
6.1.1 Blender assembly— Plug the power supply cord of the
committee E35.22 on Pesticide Formulations and Delivery Systems.
blender into the power outlet of a variable transformer with a
Current edition approved Oct. 1, 2009. Published November 2009. Originally
0 to 120V output. Plug the transformer into a 115V ground
approved in 2004. Last previous edition approved in 2004 as E2407 – 04. DOI:
10.1520/E2407-04R09.
fault protected (GFCI) power source. Using water, an elec-
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
tronic balance, and a marking pen, mark 50 mLgraduations on
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
theglassblendercup,from200to1000mL.Thisiseasilydone
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. by placing the blender cup on the balance, taring the balance,
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E2407 − 04 (2009)
then adding 50 g water and marking the water level on the 8. Procedure
exterior of the cup. Continue adding 50 g water at a time and
8.1 Equipment check
marking the water level until the cup contains 1000 g. See Fig.
8.1.1 Assemble the apparatus as described in 6.1.
1.
8.1.2 Generate foam as described below in 8.2-8.5.
6.2 Electronic balance accurate to 0.01 g,
8.1.3 Observe the foam over the next 5 min. The foam will
6.3 Stopwatch, and
separate into two layers (foam and liquid) but the total volume
6.4 Disposable polyethylene pipet, 7 mL volume or equiva-
of the foam and liquid should not decrease by more than about
lent.
25 mLduring this period. Significant loss of foam suggests the
blender cup may have residual antifoam present. In this event,
7. Reagents
wash the blender cup with detergent and thoroughly rinse, then
7.1 Def
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