U.S. patent application number 09/824289 was filed with the patent office on 2001-10-18 for stable arylpyrrole particles, process for their preparation and suspension concentrate compositions comprising them.
This patent application is currently assigned to Intellectual Property Department American Cyanamid Company. Invention is credited to Brunt, Steven, Chou Schaaf, Mimi Yih-Pei, Donoghue, Edward S., Goldsmith, Andrew Evelyn, Mowery, Patrick C., Rajan, Srinivasan, Walker, Anthony Francis, Xu, Jian James.
Application Number | 20010031879 09/824289 |
Document ID | / |
Family ID | 26696665 |
Filed Date | 2001-10-18 |
United States Patent
Application |
20010031879 |
Kind Code |
A1 |
Chou Schaaf, Mimi Yih-Pei ;
et al. |
October 18, 2001 |
Stable arylpyrrole particles, process for their preparation and
suspension concentrate compositions comprising them
Abstract
The present invention relates to arylpyrrole particles which are
prepared by a process in which the particles are aged and milled,
and pesticidal suspension concentrate compositions comprising them.
The size of the particles of this invention remains surprisingly
stable during storage.
Inventors: |
Chou Schaaf, Mimi Yih-Pei;
(Princeton, NJ) ; Brunt, Steven; (Yardley, PA)
; Xu, Jian James; (Buena Park, CA) ; Goldsmith,
Andrew Evelyn; (Waterlooville, GB) ; Walker, Anthony
Francis; (Fareham, GB) ; Mowery, Patrick C.;
(Morrisville, PA) ; Donoghue, Edward S.;
(Titusville, NJ) ; Rajan, Srinivasan; (Newton,
PA) |
Correspondence
Address: |
BASE Corporation
Patent Law Department
P.O. Box 400
Princeton
NJ
08543-0400
US
|
Assignee: |
Intellectual Property Department
American Cyanamid Company
5 Giralda Farms
Madison
NJ
07940-0874
|
Family ID: |
26696665 |
Appl. No.: |
09/824289 |
Filed: |
April 2, 2001 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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09824289 |
Apr 2, 2001 |
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09286967 |
Apr 6, 1999 |
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6242613 |
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60023045 |
Aug 2, 1996 |
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Current U.S.
Class: |
548/541 ;
548/557; 548/561 |
Current CPC
Class: |
A01N 25/04 20130101;
A01N 2300/00 20130101; A01N 43/36 20130101; A01N 43/36 20130101;
A01N 43/36 20130101; C07D 207/416 20130101 |
Class at
Publication: |
548/541 ;
548/557; 548/561 |
International
Class: |
C07D 27/36; C07D
27/42 |
Claims
What is claimed is:
1. A stable arylpyrrole particle comprising an arylpyrrole which
can exist as at least two different polymorphs, at least one of
which is particle size stable during storage, wherein the ratio of
stable polymorph to unstable polymorph in said particle is greater
than about 1:4, said arylpyrrole being represented by the formula
3wherein X is H, F, Cl, Br, I, C.sub.1-C.sub.4haloalkyl or
S(O).sub.m(C.sub.1-C.sub.4haloalkyl); Y is F, Cl, Br, I,
C.sub.1-C.sub.4haloalkyl or CN; W is CN or NO.sub.2; A is
C.sub.1-C.sub.4alkyl optionally substituted with one to three
halogen atoms, one cyano, one hydroxy, one C.sub.1-C.sub.4alkoxy,
one C.sub.1-C.sub.4alkylthio, one phenyl optionally substituted
with C.sub.1-C.sub.3alkyl, C.sub.1-C.sub.3alkoxy, or one to three
halogen atoms, one phenoxy optionally substituted with one to three
halogen atoms, or one benzyloxy optionally substituted with one
halogen atom, C.sub.1-C.sub.4carbalkoxymethyl,
C.sub.3-C.sub.4alkenyl optionally substituted with one to three
halogen atoms, cyano, C.sub.3-C.sub.4alkynyl optionally substituted
with one halogen atom, di-(C.sub.1-C.sub.4alkyl)aminocarbonyl, or
benzoyl optionally substituted with one to three halogen atoms or
one to three C.sub.1-C.sub.4alkyl groups; L is H, F, Cl or Br; M
and R are each independently H, C.sub.1-C.sub.3alkyl,
C.sub.1-C.sub.3alkoxy, C.sub.1-C.sub.3alkylthio,
C.sub.1-C.sub.3alkylsulfinyl, C.sub.1-C.sub.3alkylsulfonyl, cyano,
F, Cl, Br, I, nitro, C.sub.1-C.sub.3haloalkyl, R.sub.1CF.sub.2Z,
R.sub.2CO or NR.sub.3R.sub.4, or when M and R are on adjacent
positions and taken with the carbon atoms to which they are
attached they may form a ring in which MR represents the structure:
--OCH.sub.2O--, --OCF.sub.2O--,
--OCR.sub.6R.sub.7CR.sub.8R.sub.9O--, --OCH.sub.2CH.sub.2--,
--OCH.sub.2CH.sub.2CH.sub.2-- or --CH.dbd.CH--CH.dbd.CH--; Z is
S(O).sub.n or O; R.sub.1 is H, F, CHF.sub.2, CHFCl or CF.sub.3;
R.sub.2 is C.sub.1-C.sub.3alkyl, C.sub.1-C.sub.3alkoxy or
NR.sub.3R.sub.4; R.sub.3 is H or C.sub.1-C.sub.3alkyl; R.sub.4 is
H, C.sub.1-C.sub.3alkyl or R.sub.5CO; R.sub.5 is H or
C.sub.1-C.sub.3alkyl; R.sub.6, R.sub.7, R.sub.8 and R.sub.9 are
each independently hydrogen, halogen or C.sub.1-C.sub.3alkyl; and m
and n are each independently an integer of 0, 1 or 2.
2. A particle according to claim 1 wherein said arylpyrrole is
represented by the formula 4wherein X, Y, W, A, L, M and R are as
defined in claim 1.
3. A particle according to claim 3 wherein X and Y are each
independently Cl, Br or CF.sub.3; W is CN; A is
C.sub.1-C.sub.4alkoxymethyl; L is H or F; M is H, F, Cl or Br; and
R is F, Cl, Br, CF.sub.3 or OCF.sub.3.
4. A particle according to claim 3 wherein said arylpyrrole is
chlorfenapyr.
5. A particle according to claim 4 wherein said ratio is about 1:1
to 1:0.
6. A process for the preparation of an arylpyrrole having a stable
crystalline form which does not increase significantly in particle
size during storage which comprises: a) providing a first mixture
comprising arylpyrrole particles having a volume mean diameter of
less than about 100.mu., a dispersing agent and water; b) holding
the first mixture in a temperature range of about 25.degree. C. to
80.degree. C. to obtain an aged mixture; and c) milling the aged
mixture, if necessary, to obtain stable arylpyrrole particles
having a volume mean diameter of less than about 15.mu..
7. The process according to claim 6 wherein the arylpyrrole has the
structural formula 5wherein X is H, F, Cl, Br, I,
C.sub.1-C.sub.4haloalkyl or S(O).sub.m(C.sub.1-C.sub.4haloalkyl); Y
is F, Cl, Br, I, C.sub.1-C.sub.4haloalkyl or CN; W is CN or
NO.sub.2; A is C.sub.1-C.sub.4alkyl optionally substituted with one
to three halogen atoms, one cyano, one hydroxy, one
C.sub.1-C.sub.4alkoxy, one C.sub.1-C.sub.4alkylthio, one phenyl
optionally substituted with C.sub.1-C.sub.3alkyl,
C.sub.1-C.sub.3alkoxy, or one to three halogen atoms, one phenoxy
optionally substituted with one to three halogen atoms, or one
benzyloxy optionally substituted with one halogen atom,
C.sub.1-C.sub.4carbalkoxymethyl, C.sub.3-C.sub.4alkenyl optionally
substituted with one to three halogen atoms, cyano,
C.sub.3-C.sub.4alkynyl optionally substituted with one halogen
atom, di-(C.sub.1-C.sub.4alkyl)aminocarbonyl, or benzoyl optionally
substituted with one to three halogen atoms or one to three
C.sub.1-C.sub.4alkyl groups; L is H, F, Cl or Br; M and R are each
independently H, C.sub.1-C.sub.3alkyl, C.sub.1-C.sub.3alkoxy,
C.sub.1-C.sub.3alkylthio, C.sub.1-C.sub.3alkylsulfinyl,
C.sub.1-C.sub.3alkylsulfonyl, cyano, F, Cl, Br, I, nitro,
C.sub.1-C.sub.3haloalkyl, R.sub.1CF.sub.2Z, R.sub.2CO or
NR.sub.3R.sub.4, or when M and R are on adjacent positions and
taken with the carbon atoms to which they are attached they may
form a ring in which MR represents the structure: --OCH.sub.2O--,
--OCF.sub.2O--, --OCR.sub.6R.sub.7CR.sub.8R.sub.9O--,
--OCH.sub.2CH.sub.2--, --OCH.sub.2CH.sub.2CH.sub.2-- or
--CH.dbd.CH--CH.dbd.CH--; Z is S(O).sub.n or O; R.sub.1 is H, F,
CHF.sub.2, CHFCl or CF.sub.3; R.sub.2 is C.sub.1-C.sub.3alkyl,
C.sub.1-C.sub.3alkoxy or NR.sub.3R.sub.4; R.sub.3 is H or
C.sub.1-C.sub.3alkyl; R.sub.4 is H, C.sub.1-C.sub.3alkyl or
R.sub.5CO; R.sub.5 is H or C.sub.1-C.sub.3alkyl; R.sub.6, R.sub.7,
R.sub.8 and R.sub.9 are each independently hydrogen, halogen or
C.sub.1-C.sub.3alkyl; and m and n are each independently an integer
of 0, 1 or 2.
8. The process according to claim 7 wherein the arylpyrrole has the
structural formula 6wherein X, Y, W, A, L, M and R are as defined
in claim 7.
9. The process according to claim 8 wherein X and Y are each
independently Cl, Br or CF.sub.3; W is CN; A is
C.sub.1-C.sub.4alkoxymethyl; L is H or F; M is H, F, Cl or Br; and
R is F, Cl, Br, CF.sub.3 or OCF.sub.3.
10. The process according to claim 9 wherein the arylpyrrole is
chlorfenapyr.
11. The process according to claim 10 wherein the chlorfenapyr
particles in the first mixture comprise less than 80 percent of
Polymorph I.
12. The process according to claim 6 wherein the arylpyrrole
particles used in step a have a volume mean diameter of about 0.5
.mu.m to 30 .mu.m.
13. The process according to claim 6 wherein the temperature range
used in step b is about 40.degree. C. to 60.degree. C.
14. The process according to claim 6 wherein the first mixture is
held in the temperature range for about 1 hour to 72 hours.
15. The process according to claim 6 wherein the first mixture is
held in the temperature range for about 2 hours to 48 hours.
16. The process according to claim 6 wherein the first mixture is
held in the temperature range for about 2 hours to 24 hours.
17. The process according to claim 16 wherein the temperature range
used in step b is about 40.degree. C. to 60.degree. C.
18. The process according to claim 6 wherein the dispersing agent
is a salt of the condensation products of formaldehyde with the
sulfonation products of polycyclic aromatic compounds.
19. The process according to claim 18 wherein the salt of the
condensation products of formaldehyde with the sulfonation products
of polycyclic aromatic compounds is the sodium sulfonate of
naphthalene formaldehyde condensates.
20. The process according to claim 6 wherein the first mixture
comprises about 10% to 85% by weight of arylpyrrole particles,
about 0.1% to 3.5% by weight of a dispersing agent, about 0.5% to
8.5% by weight of a steric stabilizer, about 0.1% to 2% by weight
of a suspending agent, up to about 25% by weight of an antifreeze
agent, up to about 2% by weight of an antifoam agent, up to about
1% by weight of a preservative, up to about 1% by weight of a
thickening agent, and water.
21. The process according to claim 6 wherein the first mixture
comprises 20% to 70% by weight of arylpyrrole particles having a
volume mean diameter of less than about 100 .mu.m, 0.5% to 2.5% by
weight of a dispersing agent, 1.5% to 6% by weight of a steric
stabilizer, 0.1% to 2% by weight of a suspending agent, 5% to 20%
by weight of an antifreeze agent, 0.1% to 2% by weight of an
antifoam agent, 0.01% to 1% by weight of a preservative and
water.
22. The process according to claim 21 wherein the dispersing agent
is a salt of the condensation products of formaldehyde with the
sulfonation products of polycyclic aromatic compounds; the steric
stabilizer is an ethylene oxide/propylene oxide block copolymer;
the suspending agent is selected from the group consisting of a
magnesium aluminum silicate, a magnesium silicate and an aluminum
silicate; the antifreeze agent is a glycol; and the thickening
agent is selected from the group consisting of xanthan gum,
carrageenan, pectin, gum arabic and guar rubber.
23. The process according to claim 21 wherein the dispersing agent
is the sodium sulfonate of naphthalene formaldehyde condensates,
the steric stabilizer is an alpha-butyl-omega-hydroxy-ethylene
oxide-propylene oxide block copolymer, the suspending agent is a
magnesium aluminum silicate, the antifreeze agent is propylene
glycol, and the thickening agent is xanthan gum.
24. The process according to claim 23 wherein the arylpyrrole
particles used in step a have a volume mean diameter of about 0.5
.mu.m to 30 .mu.m.
25. The process according to claim 24 wherein the temperature range
used in step b is about 40.degree. C. to 60.degree. C.
26. The process according to claim 23 wherein the first mixture is
held in the temperature range for about 1 hour to 72 hours.
27. The process according to claim 23 wherein the first mixture is
held in the temperature range for about 2 hours to 48 hours.
28. The process according to claim 23 wherein the first mixture is
held in the temperature range for about 2 hours to 24 hours.
29. Stable arylpyrrole particles prepared by the process of claim
6.
30. A suspension concentrate composition which comprises about 10%
to 50% by weight of stable arylpyrrole particles prepared by the
process of claim 6, about 0.1% to 2% by weight of a dispersing
agent, about 0.5% to 5% by weight of a steric stabilizer, about
0.1% to 1% by weight of a suspending agent, about 0.01% to 0.5% by
weight of a thickening agent, about 5% to 15% by weight of an
antifreeze agent, up to about 1% by weight of an antifoam agent, up
to about 0.5% by weight of a preservative and water.
31. The composition according to claim 30 wherein the stable
arylpyrrole particles have a volume mean diameter of about 0.5
.mu.m to 10 .mu.m.
32. The composition according to claim 31 wherein said ratio is
about 1:1 to 1:0.
33. A composition according to claim 32 wherein said arylpyrrole is
chlorfenapyr.
Description
BACKGROUND OF THE INVENTION
[0001] Pests such as insects and acarids cause tremendous global
economic losses by reducing crop yields and lowering crop quality.
Arylpyrrole compounds are useful for the control of insect and
acarid pests. However, it has been found that arylpyrrole particles
present in suspension concentrate may not maintain a stable
particle size. In particular, it has been found that certain
arylpyrrole particles grow to an unacceptable size during
storage.
[0002] Certain pesticidal arylpyrrole compounds and methods for
their preparation and use are described in U.S. Pat. Nos. 5,010,098
and 5,233,051; and Canadian Patent Application Number 2,076,937.
Chlorfenapyr
(4-bromo-2-(p-chlorophenyl)-1-(ethoxymethyl)-5-(trifluoromethyl)pyrrole-3-
-carbonitrile) was the first arylpyrrole pesticide to be
commercialized. Chlorfenapyr and methods for its preparation and
use are described in U.S. Pat. No. 5,010,098.
[0003] Suspension concentrate compositions comprising arylpyrrole
particles are disclosed in U.S. Pat. No. 5,496,845. However, it has
been found that the particle size stability of the arylpyrrole
compounds in the reference compositions is variable. Commonly,
arylpyrrole particles known in the art increase in size during
storage, i.e., an initial number of relatively small particles
becomes a smaller number of larger particles. It is desirable to
have particles whose sizes are predictably stable over time, to
avoid undesired variations in the characteristics of formulations
containing these particles.
SUMMARY OF THE INVENTION
[0004] The present invention provides stable arylpyrrole particles
wherein more than about 20% of the arylpyrrole is in a stable
crystalline form thereof.
[0005] The present invention further provides a process for the
preparation of stable arylpyrrole particles which process
comprises:
[0006] a) providing a first mixture comprising arylpyrrole
particles, a dispersing agent and water;
[0007] b) keeping the first mixture in a temperature range of about
25.degree. C. to 80.degree. C. to obtain an aged mixture; and
[0008] c) milling, if necessary, the aged mixture to obtain
stabilized arylpyrrole particles.
[0009] The present invention also provides stable arylpyrrole
particles prepared by the process of this invention, and suspension
concentrate compositions comprising arylpyrrole particles of this
invention.
[0010] It is, therefore, an object of the present invention to
provide a process for stabilizing arylpyrrole particles.
[0011] It is another object of this invention to provide stable
arylpyrrole particles.
[0012] It is a further object of this invention to provide
suspension concentrate compositions which comprise stable
arylpyrrole particles.
[0013] These and other objects and advantages of the present
invention will become more apparent from the detailed description
thereof set forth below, and from the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 is the characteristic infrared absorption spectrum of
the chlorfenapyr polymorph designated as "Polymorph I".
[0015] FIG. 2 is the characteristic infrared absorption spectrum of
the chlorfenapyr polymorph designated as "Polymorph II".
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0016] In one important aspect, the present invention provides
stable arylpyrrole particles which grow within allowable or
acceptable limits during storage in suspension concentrate
compositions. We have discovered that arylpyrroles may exist in at
least two crystal forms. The predominant crystal forms of
chlorfenapyr, for example, are designated herein as Polymorph I and
Polymorph II. Polymorph I has a melting point of 95.degree. C. and
the characteristic infrared absorption spectrum shown in FIG. 1.
Polymorph II has a melting point of 101.degree. C. and the
characteristic infrared absorption spectrum shown in FIG. 2.
[0017] We have further discovered that certain arylpyrrole crystal
forms are more stable than other arylpyrrole crystal forms.
Surprisingly, compositions containing chlorfenapyr particles having
a Polymorph I to Polymorph II ratio greater than about 1:4 are
significantly more storage stable than compositions having a
Polymorph I to Polymorph II ratio of 1:4 to 0:1.
[0018] Advantageously, the present invention relates to arylpyrrole
particles comprising a stabilizing amount of a stable crystal form
of the arylpyrrole. The stabilizing amount of the stable crystal
form is that amount which prevents unacceptable particle growth
during storage in compositions comprising the arylpyrrole particles
and water. Unacceptable particle growth may reduce the pesticidal
efficacy of the arylpyrroles and/or detrimentally affects the
physical properties of the compositions including their
dilution/use characteristics.
[0019] Heretofore, the stability of arylpyrrole particles was
unpredictable because commercial production methods provided
particles having widely varying amounts of the stable crystal form.
The existence and importance of the different crystal forms were
not known and understood, and there was no known method for
achieving predictably stable particles.
[0020] It has now been discovered that different crystal forms, or
polymorphs, can be identified. It has also been found that
arylpyrrole suspension concentrate compositions comprising a high
percentage of one polymorph are more stable than suspension
concentrate compositions comprising a low percentage of that
polymorph. In particular, chlorfenapyr suspension concentrate
compositions comprising chlorfenapyr particles containing a high
percentage of Polymorph I are more stable than suspension
concentrate compositions containing a low percentage of Polymorph
I. Because the amount of each crystal form can be measured, stable
arylpyrrole suspension concentrates can now be achieved
consistently and predictably by forming the suspension from
arylpyrrole particles having sufficient stable crystal content.
[0021] Arylpyrrole particles having the desired amount of stable
crystal form may be selected from among the variety of particles
formed by commercial production processes. Batches of an
arylpyrrole that have different ratios of stable crystal form to
unstable crystal form may be blended, using blending methods known
in the art, to achieve a desired ratio. The ratio of the polymorphs
present in a particular batch of chlorfenapyr particles may be
determined by infrared analysis.
[0022] The chlorfenapyr particles of the present invention
preferably comprise a Polymorph I to Polymorph II ratio of about
1:3 to 1:0 and more preferably about 1:1 to 1:0.
[0023] The volume mean diameter of the arylpyrrole particles of
this invention is preferably less than about 100 .mu.m, more
preferably less than about 15 .mu.m, and most preferably about 0.5
.mu.m to 10 .mu.m.
[0024] The arylpyrrole particles of this invention may be
formulated as suspension concentrates, dispersible granules,
wettable powders, dusts, dust concentrates, microemulsions and the
like, by methods well-known in the art. These compositions include
the arylpyrrole particles of this invention and one or more
agronomically acceptable solid or liquid carriers.
[0025] In particular, the present invention provides stable
suspension concentrate compositions which comprise about 10% to 50%
by weight of the arylpyrrole particles of this invention, about
0.1% to 2% by weight of a dispersing agent, about 0.5% to 5% by
weight of a steric stabilizer, about 0.1% to 1% by weight of a
suspending agent, about 0.01% to 0.5% by weight of a thickening
agent, up to about 15% by weight of an antifreeze agent, up to
about 1% by weight of an antifoam agent, up to about 0.5% by weight
of a preservative, and water.
[0026] The stable suspension concentrate compositions of this
invention preferably comprise 10% to 40% by weight of the
arylpyrrole particles, 0.5% to 1.5% by weight of a dispersing
agent, 1.5% to 3.5% by weight of a steric stabilizer, 0.1% to 1% by
weight of a suspending agent, 0.01% to 0.5% by weight of a
thickening agent, 5% to 10% by weight of an antifreeze agent, 0.1%
to 1% by weight of an antifoam agent, 0.01% to 0.5% by weight of a
preservative, and water.
[0027] In the suspension concentrate compositions of the present
invention, the ratio of the total amount of the dispersing agent
and the steric stabilizer to the arylpyrrole particles is
preferably about 1:5 to 1:15 and more preferably about 1:8 to
1:10.
[0028] The volume mean diameter of the arylpyrrole particles
present in the suspension concentrate compositions of this
invention is preferably less than 15 .mu.m, more preferably about
0.5 .mu.m to 10 .mu.m, and most preferably about 0.5 .mu.m to 4
.mu.m.
[0029] Arylpyrrole compounds of this invention include those having
the structural formula I 1
[0030] wherein
[0031] X is H, F, Cl, Br, I, C.sub.1-C.sub.4haloalkyl or
S(O).sub.m(C.sub.1-C.sub.4haloalkyl);
[0032] Y is F, Cl, Br, I, C.sub.1-C.sub.4haloalkyl or CN;
[0033] W is CN or NO.sub.2;
[0034] A is
[0035] C.sub.1-C.sub.4alkyl optionally substituted with
[0036] one to three halogen atoms,
[0037] one cyano,
[0038] one hydroxy,
[0039] one C.sub.1-C.sub.4alkoxy,
[0040] one C.sub.1-C.sub.4alkylthio,
[0041] one phenyl optionally substituted with C.sub.1-C.sub.3alkyl,
C.sub.1-C.sub.3alkoxy, or one to three halogen atoms,
[0042] one phenoxy optionally substituted with one to three halogen
atoms, or
[0043] one benzyloxy optionally substituted with one halogen
atom,
[0044] C.sub.1-C.sub.4carbalkoxymethyl,
[0045] C.sub.3-C.sub.4alkenyl optionally substituted with one to
three halogen atoms,
[0046] cyano,
[0047] C.sub.3-C.sub.4alkynyl optionally substituted with one
halogen atom,
[0048] di-(C.sub.1-C.sub.4alkyl)aminocarbonyl, or
[0049] benzoyl optionally substituted with one to three halogen
atoms or one to three C.sub.1-C.sub.4alkyl groups;
[0050] L is H, F, Cl or Br;
[0051] M and R are each independently H, C.sub.1-C.sub.3alkyl,
C.sub.1-C.sub.3alkoxy, C.sub.1-C.sub.3alkylthio,
C.sub.1-C.sub.3alkylsulf- inyl, C.sub.1-C.sub.3alkylsulfonyl,
cyano, F, Cl, Br, I, nitro, C.sub.1-C.sub.3haloalkyl,
R.sub.1CF.sub.2Z, R.sub.2CO or NR.sub.3R.sub.4, or when M and R are
on adjacent positions and taken with the carbon atoms to which they
are attached they may form a ring in which MR represents the
structure:
[0052] --OCH.sub.2O--, --OCF.sub.2O--,
--OCR.sub.6R.sub.7CR.sub.8R.sub.9O-- -, --OCH.sub.2CH.sub.2--,
--OCH.sub.2CH.sub.2CH.sub.2-- or --CH.dbd.CH--CH.dbd.CH--;
[0053] Z is S(O).sub.n or O;
[0054] R.sub.1 is H, F, CHF.sub.2, CHFCl or CF.sub.3;
[0055] R.sub.2 is C.sub.1-C.sub.3alkyl, C.sub.1-C.sub.3alkoxy or
NR.sub.3R.sub.4;
[0056] R.sub.3 is H or C.sub.1-C.sub.3alkyl;
[0057] R.sub.4 is H, C.sub.1-C.sub.3alkyl or R.sub.5CO;
[0058] R.sub.5 is H or C.sub.1-C.sub.3alkyl;
[0059] R.sub.6, R.sub.7, R.sub.8 and R.sub.9 are each independently
hydrogen, halogen or C.sub.1-C.sub.3alkyl; and
[0060] m and n are each independently an integer of 0, 1 or 2.
[0061] Preferred arylpyrrole compounds suitable for use in the
present invention are those having the structural formula II 2
[0062] wherein X, Y, W, A, L, M and R are as described above.
[0063] More preferred arylpyrrole compounds which are particularly
suitable for use in this invention are those having the structural
formula II wherein
[0064] X and Y are each independently Cl, Br or CF.sub.3;
[0065] W is CN;
[0066] A is C.sub.1-C.sub.4alkoxymethyl;
[0067] L is H or F;
[0068] M is H, F, Cl or Br; and
[0069] R is F, Cl, Br, CF.sub.3 or OCF.sub.3.
[0070] Another important aspect of this invention is a process for
preparing stable arylpyrrole particles, which process
comprises:
[0071] a) providing a first mixture comprising arylpyrrole
particles, a dispersing agent and water;
[0072] b) holding the first mixture in a temperature range of about
25.degree. C. to 80.degree. C. to obtain an aged mixture; and
[0073] c) milling the aged mixture, if necessary, to obtain
stabilized arylpyrrole particles.
[0074] The process of the present invention is hereinafter
sometimes referred to as the "stabilization process". In this
context, stabilization refers to maintaining a relatively constant
particle size. Stable particles do not grow significantly during
storage at room temperature for up to three months or longer in a
suspension concentrate composition.
[0075] It has now been discovered that when the stable polymorph
content of the arylpyrrole is less than approximately 80%,
especially less than about 50%, and most especially less than about
25% by weight, the stability of the arylpyrrole particles may be
enhanced by the process of this invention. The amount of time
needed to obtain a sufficiently aged mixture will vary, and will
depend to some degree on the initial crystal form content, the
particle size, and the temperature. The process of this invention
is especially useful for stabilizing chlorfenapyr particles.
[0076] To overcome the problems associated with the use of
arylpyrrole particles containing the less stable polymorph, it is
desirable to subject all arylpyrrole particles to the stabilization
process of this invention. The stabilization process of this
invention is especially useful for improving the particle size
stability of chlorfenapyr containing less than 80%/ of Polymorph
I.
[0077] The volume mean diameter of the arylpyrrole particles
utilized in the process of this invention is preferably less than
about 100 .mu.m and more preferably about 0.5 .mu.m to 30 .mu.m.
The volume mean diameter of the stabilized arylpyrrole particles
prepared by the stabilization process is preferably about 0.5 .mu.m
to 10 .mu.m and more preferably about 0.5 .mu.m to 4 .mu.m.
[0078] Dispersing agents suitable for use in this invention
include, but are not limited to, the salts of the condensation
products of formaldehyde with the sulfonation products of
polycyclic aromatic compounds; the salts of polyacrylic acids; the
condensation products of fatty acids or aliphatic amines or amides
containing at least about twelve carbon atoms in the molecule with
ethylene oxide and/or propylene oxide; fatty acid esters of
glycerol, sorbitan, sucrose or pentaerythritol and their
condensation products with ethylene oxide and/or propylene oxide;
condensation products of fatty alcohols or alkyl phenols with
ethylene oxide and/or propylene oxide and their sulfates or
sulfonates; and alkali or alkaline earth metal salts of sulfuric or
sulfonic acid esters containing at least ten carbon atoms in the
molecule, for example sodium lauryl sulfate and dodecylbenzene
sulfonate.
[0079] Preferred dispersing agents include the salts of the
condensation products of formaldehyde with the sulfonation products
of polycyclic aromatic compounds such as the salts of the
condensation products of formaldehyde with naphthalene sulfonates,
petroleum sulfonates and lignin sulfonates. More preferred
dispersing agents include the sodium sulfonate of naphthalene
formaldehyde condensates such as MORWET.RTM. D425 (Witco, Houston,
Tex.), LOMAR.RTM. PW (Henkel, Cincinnati, Ohio) and DARVAN.RTM. 1
(R.T. Vanderbilt Co., Norwalk, Conn.).
[0080] In a preferred process of the present invention, the first
mixture is held in a temperature range of about 40.degree. C. to
60.degree. C. In another preferred process of this invention, the
first mixture is preferably held in the temperature range for about
1 hour to 72 hours, more preferably for about 2 hours to 48 hours
and most preferably for about 2 hours to 24 hours.
[0081] The first mixture of the present invention preferably
comprises about 10% to 85% by weight of arylpyrrole particles,
about 0.1% to 3.5% by weight of a dispersing agent, about 0.5% to
8.5% by weight of a steric stabilizer, about 0.1% to 2% by weight
of a suspending agent, up to about 25% by weight of an antifreeze
agent, up to about 2% by weight of an antifoam agent, up to about
1% by weight of a preservative, up to about 1% by weight of a
thickening agent, and water. More preferably, the first mixture
comprises 20% to 70% by weight of arylpyrrole particles having a
volume mean diameter of less than about 100 .mu.m, 0.5% to 2.5% by
weight of a dispersing agent, 1.5% to 6% by weight of a steric
stabilizer, 0.1% to 2% by weight of a suspending agent, 5% to 20%
by weight of an antifreeze agent, 0.1% to 2% by weight of an
antifoam agent, 0.01% to 1% by weight of a preservative and
water.
[0082] The present invention also provides suspension concentrate
compositions which comprise about 10% to 50% by weight of
stabilized arylpyrrole particles prepared by the process of this
invention, about 0.1% to 2% by weight of a dispersing agent, about
0.5% to 5% by weight of a steric stabilizer, about 0.1% to 1% by
weight of a suspending agent, about 0.01% to 0.5% by weight of a
thickening agent, about 5% to 15% by weight of an antifreeze agent,
up to about 1% by weight of an antifoam agent, up to about 0.5% by
weight of a preservative, and water.
[0083] The suspension concentrate compositions of this invention
preferably comprise 10% to 40% by weight of stabilized arylpyrrole
particles having a volume mean diameter of 0.5 .mu.m to 10 .mu.m,
0.5% to 1.5% by weight of a dispersing agent, 1.5% to 3.5% by
weight of a steric stabilizer, 0.1% to 1% by weight of a suspending
agent, 0.01% to 0.5% by weight of a thickening agent, 5% to 10% by
weight of an antifreeze agent, 0.1% to 1% by weight of an antifoam
agent, 0.01% to 0.5% by weight of a preservative, and water.
[0084] In the suspension concentrate compositions and the preferred
first mixtures of the present invention, the ratio of the total
amount of the dispersing agent and the steric stabilizer to the
appropriate arylpyrrole particles is preferably about 1:5 to 1:15
and more preferably about 1:8 to 1:10.
[0085] Steric stabilizers suitable for use in the present invention
include, but are not limited to, polymers of ethylene oxide and
copolymers of ethylene oxide and propylene oxide such as ethylene
oxide/propylene oxide block copolymers. Preferred steric
stabilizers are butyl-omega-hydroxypoly(oxypropylene)block polymers
with poly(oxyethylene) having an average molecular weight in a
range of about 2,400 to 3,500 with
alpha-butyl-omega-hydroxy-ethylene oxide-propylene oxide block
copolymers such as TOXIMUL.RTM. 8320 (Stepan Chemical Co., Winder,
Ga.), WITCONOL.RTM. NS 500 LQ (Witco) and TERGITOL.RTM. XD (Union
Carbide, Danbury, Conn.) being most preferred.
[0086] Suspending agents suitable for use in this invention
include, but are not limited to, natural and synthetic clays and
silicates, for example natural silicas such as diatomaceous earths;
magnesium silicates such as talcs, magnesium aluminum silicates
such as attapulgites and vermiculites; and aluminum silicates such
as kaolinites, montmorillonites and micas. Preferred suspending
agents are magnesium silicates, magnesium aluminum silicates and
aluminum silicates with magnesium aluminum silicates such as
VANGEL.RTM. ES (R. T. Vanderbilt), VEEGUM.RTM. (R. T. Vanderbilt),
VEEGUM.RTM. T (R. T. Vanderbilt) and GELWHITE.RTM. (Southern Clay
Products, Gonzales, Tex.) being most preferred.
[0087] Thickening agents useful in this invention include, but are
not limited to, natural thickening agents such as xanthan gum,
carrageenan, pectin, gum arabic, guar rubber and the like;
semisynthetic thickening agents such as the methylation products,
carboxyalkylation products and hydroxyalkylation products of
cellulose or starch derivatives; and synthetic thickening agents
such as polyacrylates, polymaleinates and polyvinylpyrrolidone with
xanthan gums such as KELZAN.RTM. (Kelco, San Diego, Calif.) and
RHODOPOL.RTM. 23 (Rhone-Poulenc, Cranbury, N.J.) being preferred
thickening agents.
[0088] Antifreeze agents suitable for use in the present invention
include glycols such as propylene glycol, ethylene glycol and the
like with propylene glycol being preferred. Suitable antifoam
agents include emulsions of silicone oils, emulsions of fatty
alcohols and the like. Preservatives suitable for use in this
invention include 1,2-benzisothiazolin-3-one, epichlorohydrin,
phenylglycidyl ether, allylglycidyl ether, formaldehyde
compositions and the like with 1,2-benzisothiazolin-3-one being
preferred.
[0089] Suspension concentrate compositions of the present invention
may conveniently be prepared by admixing arylpyrrole particles, a
dispersing agent, a steric stabilizer, a suspending agent and an
antifreeze agent with water to obtain a first mixture, holding the
first mixture according to the process of this invention to obtain
an aged mixture, milling the aged mixture to obtain a mixture
comprising stabilized arylpyrrole particles, and admixing the
mixture comprising stabilized arylpyrrole particles with a
thickening agent and additional water to obtain the desired
suspension concentrate composition.
[0090] The suspension concentrate compositions of this invention
preferably have a pH of about pH 5 to pH 9 and more preferably
about pH 6 to pH 8. To adjust the pH into the desired range, acids
such as acetic acid, propionic acid, sulfuric acid, phosphoric
acid, hydrochloric acid and the like may be used.
[0091] In order to facilitate a further understanding of the
invention, the following examples are presented to illustrate more
specific details thereof. The scope of the invention is not limited
to the embodiments illustrated, but includes the entire subject
matter of the appended claims.
EXAMPLE 1
[0092] Preparation of Stabilized Chlorfenapyr Particles
[0093] Propylene glycol (331 g), a 17% 1,2-benzisothiazolin-3-one
solution (PROXEL.RTM. GXL, Zeneca) (6.35 g), a 30% silicone
emulsion (AF 30 IND.RTM., Harcros Chemical Co.) (29.9 g), an
alpha-butyl-omega-hydroxyl-e- thylene oxide/propylene oxide block
copolymer (TOXIMUL.RTM. 8320, Stepan Chemical Co.) (132.5 g), a
sodium sulfonate of a naphthalene formaldehyde condensate
(MORWET.RTM. D425, Witco) (44 g), magnesium aluminum silicate
(VANGEL.RTM. ES, R. T. Vanderbilt) (22.2 g), and chlorfenapyr
(1,542 g, 90% real, 0% Polymorph I) are added sequentially with
stirring to water (976 g). The resultant mixture is stirred until
homogeneous and passed through a wet milling device to obtain a
mixture identified as composition number 1 below comprising
chlorfenapyr particles having a volume mean diameter of about 1.58
.mu.m.
1 Composition Number 1 Ingredient wt/wt % Chlorfenapyr 50.00 MORWET
.RTM. D425 1.43 TOXIMUL .RTM. 8320 4.30 VANGEL .RTM. ES 0.72
Propylene glycol 10.73 AF 30 IND .RTM. 0.97 PROXEL .RTM. GXL 0.21
Water 31.65
[0094] Individual samples of composition number 1 are stirred at
40.degree. C., 55.degree. C. and 70.degree. C. for 17 hours and
passed through a wet milling device to obtain composition numbers
2, 3 and 4 comprising stabilized chlorfenapyr particles.
Composition numbers 1-4 are then stored at room temperature for two
months and the volume mean diameter of the chlorfenapyr particles
in each composition is measured. The results are summarized in
Table I.
[0095] As can be seen from the data in Table I, the volume mean
diameter of the stabilized chlorfenapyr particles present in
composition numbers 2, 3 and 4 increases significantly less than
the volume mean diameter of the chlorfenapyr particles present in
composition number 1.
2TABLE I Stability of Chlorfenapyr Particles Volume Mean Diameter
of Chlorfenapyr Initial Volume Particles (.mu.m) After Temperature
Mean Diameter of Storage at Room Comp. (.degree. C.) Stirred
Chlorfenapyr Temperature Number at for 17 Hours Particles (.mu.m)
for 2 Months 1 N/A 1.58 4.47 2 40 1.42 1.41 3 55 1.49 1.41 4 70
1.50 2.72
EXAMPLE 2
[0096] Effect of Initial Particle Size of Chlorfenapyr
Particles
[0097] Using the same procedure as described in Example 1, but
varying the particle size of the chlorfenapyr particles present in
the compositions prior to holding at 55.degree. C., composition
numbers 5-7 comprising stabilized chlorfenapyr particles are
obtained. Those compositions and composition number 8, which is
identical to composition number 1 from Example 1 except that the
chlorfenapyr particles have a volume mean diameter of 1.44 Jim, are
stored at room temperature for three weeks. The volume mean
diameter of the chlorfenapyr particles in each composition is then
measured and the results are summarized in Table II.
[0098] As can be seen from the data in Table II, the volume mean
diameter of the stabilized chlorfenapyr particles present in
composition numbers 5-7 increases significantly less than the
volume mean diameter of the chlorfenapyr particles present in
composition number 8.
[0099] It can also be seen that the smaller the particle size prior
to the stabilizing process, the more effective the stabilizing
process is.
3TABLE II Effect of Initial Particle Size of Chlorfenapyr Particles
Volume Mean Diameter of Chlorfenapyr Volume Mean Particles (.mu.m)
Diameter of Final Volume Prior to Stabilized Weeks Stored Mean
Diameter of Composition Stabilization Hours Stirred Chlorfenapyr at
Room Chlorfenapyr Number Process at 55.degree. C. Particles (.mu.m)
Temperature Particles (.mu.m) 5 >30 17 1.48 3 2.36 6 4.5 17 1.45
3 1.40 7 1.6 17 1.53 3 1.33 8* 1.44 -- -- 3 3.88 *not
stabilized
EXAMPLE 3
[0100] Effect of Various Holding Periods
[0101] Using the same procedure as described in Example 1, but
milling the chlorfenapyr particles present in the compositions to
about 4 Jim prior to holding at 55.degree. C. for various periods
of time, composition numbers 9-15 comprising stabilized
chlorfenapyr particles are obtained. Composition numbers 9-15 and
non-stabilized chlorfenapyr composition number 16, which is
identical to composition number 1 in Example 1 except that the
chlorfenapyr particles have a volume mean diameter of 1.41 .mu.m,
are stored at room temperature for three months. The volume mean
diameter of the chlorfenapyr particles in each composition is then
measured and the results are summarized in Table III.
[0102] As can be seen from the data in Table III, the volume mean
diameter of the stabilized chlorfenapyr particles present in
composition numbers 9-15 increases significantly less than the
volume mean diameter of the chlorfenapyr particles present in
composition number 16.
4TABLE III Effect of Various Holding Periods Final Volume Mean
Diameter of Volume Mean Chlorfenapyr Diameter of Particles
Chlorfenapyr Volume Mean (.mu.m) After Particles (.mu.m) Diameter
Storage at Prior to Hours of Stabilized Room Composition
Stabilization Stirred Chlorfenapyr Temperature Number Process at
55.degree. C. Particles (.mu.m) for 3 Months 9 4.1 2 1.46 1.92 10
4.1 5 1.41 1.89 11 4.1 9 1.42 1.70 12 4.1 17 1.25 1.38 13 4.0 17
1.41 1.69 14 4.0 24 1.36 1.51 15 4.0 41 1.40 1.47 16* 1.40 -- --
3.94 *not stabilized
EXAMPLE 4
[0103] Effect of Various Chlorfenapyr Polymorph Ratios on Storage
Stability of Chlorfenapyr
[0104] Using the same procedure as described in Example 1, but
using different batches of chlorfenapyr particles and holding at
55.degree. C. for 17 hours, several compositions comprising
stabilized chlorfenapyr particles are obtained and identified in
Table IV. The compositions comprising the stabilized chlorfenapyr
particles and the appropriate non-stabilized composition are stored
at room temperature for various periods of time. The volume mean
diameter of the chlorfenapyr particles in each composition is then
measured and the results are summarized in Table IV.
[0105] As can be seen from the data in Table IV, chlorfenapyr
particles present in stabilized compositions prepared using
chlorfenapyr particles having less than about 80% Polymorph I are,
in general, significantly more stable than chlorfenapyr particles
present in the corresponding non-stabilized compositions.
5TABLE IV Effect of Various Polymorph Ratios Volume Mean Diameter
of Chlorfenapyr Volume Mean Particles (.mu.m) Diameter of Final
Volume Prior to Stabilized Weeks Stored Mean Diameter Comp.
Stabilization Chlorfenapyr at Room of Chlorfenapyr Number %
Polymorph I Process Particles (.mu.m) Temp. Particles (.mu.m) 17 0
3.7 1.45 1 1.38 0 1.55 not stabilized 1 15.04 18 0 3.3 1.51 3 1.51
0 1.45 not stabilized 3 1.56 19 14 4.4 1.39 8 days 1.88 14 1.36 not
stabilized 1 2.41 20 14 1.9 1.53 12 1.48 14 1.45 not stabilized 12
2.10 21 20 2.8 1.76 6 1.97 20 1.32 not stabilized 6 5.05 22 20 3.1
1.76 6 1.64 20 1.63 not stabilized 6 2.55 23 20 4.0 1.37 2 1.28 20
1 .18 not stabilized 2 1.25 24 23 3.5 1.37 9 days 2.75 23 1.55 not
stabilized 11 days 5.82 25 55 3.4 1.56 12 1.75 55 1.47 not
stabilized 12 1.84 26 56 4.5 1.48 12 1.48 56 1.55 not stabilized 12
1.59 27 65 3.2 1.45 16 1.55 65 1.42 not stabilized 16 1.54 28 76
2.9 1.38 3 1.45 76 1.01 not stabilized 3 1.36 29 80 3.4 1.66 6 1.62
80 1.45 not stabilized 6 1.39 30 87 2.9 1.56 12 1.63 87 1.71 not
stabilized 12 1.71
EXAMPLE 5
[0106] Effect of Various Polymorph Ratios on Storage Stability of
Chlorfenapyr Suspension Concentrate Compositions
[0107] Propylene glycol (730 g), a 17% 1,2-benzisothiazolin-3-one
solution (PROXEL.RTM. GXL, Zeneca) (14.0 g), a 30% silicone
emulsion (AF 30 IND.RTM., Harcros Chemical Co.) (66.0 g),
alpha-butyl-omega-hydroxyl-ethy- lene oxide/propylene oxide block
copolymer (TOXIMUL.RTM. 8320, Stepan Chemical Co.) (292 g), sodium
sulfonate of naphthalene formaldehyde condensate (MORWET.RTM. D425,
Witco) (97.0 g), magnesium aluminum silicate (VANGEL.RTM. ES, R. T.
Vanderbilt) (49.0 g) and chlorfenapyr (3,400 g, 90% real, 6.7:1
Polymorph I to Polymorph II ratio) are added sequentially with
stirring to water (2,152 g). The resultant mixture is stirred until
homogeneous and passed through a wet milling device to obtain a
mill base wherein the chlorfenapyr particles have a volume mean
diameter of about 1.5 .mu.m. The mill base is charged into a
vessel, agitated and adjusted to a pH of pH 6.5 to pH 7.2 with
acetic acid (19.0 g). A 1% xanthan gum gel (1,459 g) (previously
prepared from xanthan gum (15.0 g), a 17%
1,2-benzisothiazolin-3-one solution (PROXEL.RTM. GXL, Zeneca) (1.0
g) and water (1,443 g)) and water (1,453 g) are added to the pH
adjusted mill base and mixing is continued to obtain the suspension
concentrate composition identified below as composition number
31.
6 Composition Number 31 Ingredient wt/wt % Chlorfenapyr.sup.1 34.94
MORWET .RTM. D425 1.00 TOXIMUL .RTM. 8320 3.00 VANGEL .RTM. ES 0.50
Propylene Glycol 7.50 AF 30 IND .RTM. 0.68 PROXEL .RTM. GXL 0.15
Xanthan Gum 0.15 Acetic Acid 0.20 Water 51.88 .sup.1Polymorph I to
Polymorph II ratio is 6.7:1
[0108] Using the same procedure, but varying the Polymorph I to
Polymorph II ratio, the suspension concentrate compositions
identified as composition numbers 32-38 in Table V are obtained.
Samples of the suspension concentrate compositions are stored at
room temperature for various periods of time. The volume mean
diameter of the chlorfenapyr particles in each sample is then
measured and the results are summarized in Table V.
[0109] As can be seen from the data in Table V, chlorfenapyr
particles comprising a Polymorph I to Polymorph II ratio of greater
than about 1:4 (composition numbers 31-35) are significantly more
stable than chlorfenapyr particles comprising a Polymorph I to
Polymorph II ratio of 1:4 to 0:1 (composition numbers 36-38).
7TABLE V Effect of Various Polymorph Ratios % Increase/ Final
Volume (Decrease) in Ratio of Initial Volume Mean Diameter Volume
Mean Polymorph I Mean Diameter Weeks Stored of Diameter of
Composition to of Chlorfenapyr at Room Chlorfenapyr Chlorfenapyr
Number Polymorph II Particles (.mu.m) Temperature Particles (.mu.m)
Particles 31 6.7:1 1.55 4 1.38 (12) 8 1.40 (11) 32 2:1 1.59 8 1.40
(14) 33 1:1 1.96 3 2.26 15 8 2.03 4 34 1:1.3 1.55 8 1.59 3 35 1:3
2.3 3 2.77 20 8 2.41 5 36 1:4 1.32 6 5.05 283 37 1:6.1 1.58 4 2.49
58 8 2.57 63 12 2.60 65 38 0:1 1.56 1 7.93 408 4 7.06 353 8 7.17
360
* * * * *