U.S. patent number RE36,042 [Application Number 08/850,708] was granted by the patent office on 1999-01-12 for shelf stable fast-core aqueous coating.
This patent grant is currently assigned to Rohm and Haas Company. Invention is credited to Roy Wesley Flynn, Francis Joseph Landy, Andrew Mercurio.
United States Patent |
RE36,042 |
Landy , et al. |
January 12, 1999 |
Shelf stable fast-core aqueous coating
Abstract
A shelf-stable fast-cure aqueous coating is disclosed. The
coating contains an anionically stabilized latex, a polyfunctional
amine and a volatile base in an amount sufficient to deprotonate
the conjugate acid of the amine.
Inventors: |
Landy; Francis Joseph
(Jenkintown, PA), Mercurio; Andrew (Gwynedd Valley, PA),
Flynn; Roy Wesley (Warrington, PA) |
Assignee: |
Rohm and Haas Company
(Philadelphia, PA)
|
Family
ID: |
23515411 |
Appl.
No.: |
08/850,708 |
Filed: |
May 2, 1997 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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32735 |
Mar 15, 1993 |
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879542 |
May 4, 1992 |
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383944 |
Jul 21, 1989 |
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Reissue of: |
340461 |
Nov 14, 1994 |
05527853 |
Jun 18, 1996 |
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Current U.S.
Class: |
524/521 |
Current CPC
Class: |
C04B
41/483 (20130101); C09D 133/064 (20130101); C09D
5/004 (20130101); C04B 41/63 (20130101); C09D
5/024 (20130101); C04B 41/009 (20130101); C04B
41/483 (20130101); C04B 41/4834 (20130101); C04B
2103/0094 (20130101); C04B 2103/402 (20130101); C04B
41/009 (20130101); C04B 28/02 (20130101); C09D
133/064 (20130101); C08L 2666/04 (20130101); C04B
2111/0075 (20130101); C08L 39/00 (20130101); C08L
33/14 (20130101) |
Current International
Class: |
C04B
41/60 (20060101); C04B 41/45 (20060101); C04B
41/63 (20060101); C09D 133/06 (20060101); C04B
41/48 (20060101); C09D 5/02 (20060101); C08L
33/00 (20060101); C08L 33/14 (20060101); C08L
39/00 (20060101); C08K 005/35 () |
Field of
Search: |
;524/521,314 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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0 066 108 |
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Dec 1982 |
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EP |
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882188 |
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Oct 1992 |
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EP |
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59-053558A |
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Mar 1984 |
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JP |
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Primary Examiner: Smith; Jeffrey T.
Attorney, Agent or Firm: Deshmukh; Sudhir G.
Parent Case Text
This application is a continuation of U.S. application Ser. No.
08/032,735 filed Mar. 15, 1993, now abandoned which is a
continuation, of application Ser. No. 879,542, filed May 4, 1992,
now abandoned, which is a continuation, of application Ser. No.
383,944, filed Jul. 21, 1989, now abandoned.
Claims
We claim:
1. A shelf-stable fast-cure aqueous coating composition consisting
essentially of:
(a) an anionically stabilized emulsion polymer having a Tg greater
than about 0.degree. C.;
(b) a water soluble polyfunctional amine polymer having from about
20% to about 100% of the monomer units by weight containing an
amine group and having no acid groups other than trace amounts;
and
(c) an amount of volatile base sufficient to raise the pH of the
composition to a point where essentially all of the polyfunctional
amine is in a non-ionic state.Iadd., a test film of said
composition having a dry time of 10 minutes as determined under a
modified ASTM D1640 dry test.Iaddend..
2. The composition of claim 1 wherein the amount of polyfunctional
amine is from about 0.25 to about 10 parts per 100 parts emulsion
solids by weight.
3. The composition of claim 2 wherein the amount of polyfunctional
amine is from about 0.4 to about 5 parts per 100 parts emulsion
solids by weight.
4. The composition of claim 3 wherein the amount of polyfunctional
amine is from about 0.6 to about 2.5 parts per 100 parts emulsion
solids by weight.
5. The coming composition of claim 1 wherein the polyfunctional
amine is polyoxazolidinoethylmethacrylate.
6. The coating composition of claim 1 wherein the polyfunctional
amine polymer contains dimethylaminopropylmethacrylamide.
7. The coming composition of claim 1 wherein the polyfunctional
amine polymer contains oxazolidinoethylmethacrylate.
8. The coating composition of claim 1 wherein the polyfunctional
amine polymer contains dimethylaminoethylmethacrylate.
9. A shelf stable fast-cure aqueous traffic paint consisting
essentially of:
(a) an anionically stabilized emulsion polymer having a Tg greater
than about 0.degree. C.;
(b) a water soluble polyfunctional amine polymer; and
(c) an amount of volatile base sufficient to raise the pH of the
composition to a point where essentially all of the polyfunctional
amine is in a non-ionic state.Iadd., a test film of said
composition having a dry time of 10 minutes as determined under a
modified ASTM D1640 dry test.Iaddend..
10. A shelf stable fast-cure aqueous paint composition consisting
essentially of:
(a) an anionically stabilized emulsion polymer having a Tg greater
than about 0.degree. C.;
(b) a water soluble polyfunctional amine; and
(c) an amount of a volatile base sufficient to raise the pH of the
composition to a point where essentially all of said polyfunctional
amine is in a non-ionic state.Iadd., a test film of said
composition having a dry time of 10 minutes as determined under a
modified ASTM D1640 dry test.Iaddend..
11. The composition of claim 10 wherein said polyfunctional amine
is polymerized from 20% to 100% by weight of amine containing
monomer units.
12. The composition of claim 11 wherein said monomer units are
selected from the group consisting of
dimethylaminopropylmethacrylamide, oxazolidinoethylmethacrylate and
dimethylaminoethylmethacrylate.
13. An exterior shelf-stable fast-cure aqueous paint composition
consisting essentially of:
(a) an anionically stabilized emulsion polymer having a Tg greater
than about 0.degree. C.;
(b) 0.6 to 2.5 parts per 100 parts of emulsion solids by weight of
a water soluble polyfunctional amine polymer having no acid groups
other than trace amounts and polymerized from
oxazolidinoethylmethacrylate monomer units; and
(c) an amount of a volatile base sufficient to raise the pH of the
composition to a point where essentially all of said polyfunctional
amine is in a non-ionic state.Iadd., a test film of said
composition having a dry time of 10 minutes as determined under a
modified ASTM D1640 dry test.Iaddend..
14. A shelf stable fast-cure aqueous traffic paint composition
consisting essentially of:
(a) an anionically stabilized emulsion polymer having a Tg greater
than about 0.degree. C.;
(b) a water soluble polyfunctional amine; and
(c) an amount of a volatile base sufficient to raise the pH of the
composition to a point where essentially all of said polyfunctional
amine is in a non-ionic state.Iadd., a test film of said
composition having a dry time of 10 minutes as determined under a
modified ASTM D1640 dry test.Iaddend..
15. The composition of claim 14 wherein said polyfunctional amine
is polymerized from 20% to 100% by weight of amine containing
monomer units.
16. The composition of claim 15 wherein said monomer units arc
selected from the group consisting of
dimethylaminopropylmethacrylamide, oxazolidinoethylmethacrylate and
dimethylaminoethylmethacrylate.
17. An exterior shelf-stable fast-cure aqueous traffic paint
composition consisting essentially of:
(a) an anionically stabilized emulsion polymer having a Tg greater
than about 0.degree. C.;
(b) 0.6 to 2.5 parts per 100 parts of emulsion solids by weight of
a water soluble polyfunctional amine polymer polymerized from
oxazolidinoethylmethacrylate monomer units; and
(c) an amount of a volatile base sufficient to raise the pH of the
composition to a point where essentially all of said polyfunctional
amine is in a non-ionic state.Iadd., a test film of said
composition having a dry time of 10 minutes as determined under a
modified ASTM D1640 dry test.Iaddend..
18. The composition of claim 17 wherein said emulsion polymer has a
Tg of 20.degree. C.
19. The composition of claim 17 wherein the amount of said
polyfunctional amine is 1.25 parts per 100 parts of emulsion
solids. .Iadd.20. The traffic paint of claim 9 wherein the
polyfunctional amine polymer is polymerized from monomer units
containing an amine or imine group..Iaddend..Iadd.21. The
composition of claim 10 wherein the polyfunctional amine is
polymerized from monomer units containing an amine or imine
group..Iaddend..Iadd.22. The composition of claim 13 wherein the
polyfunctional amine polymer is polymerized from monomer units
containing an amine or imine group..Iaddend..Iadd.23. The
composition of claim 14 wherein the polyfunctional amine is
polymerized from monomer units containing an amine or imine
group..Iaddend..Iadd.24. A shelf stable fast cure aqueous
composition consisting essentially of:
(a) an anionically stabilized emulsion polymer having a Tg greater
than about 0.degree. C.;
(b) a water soluble polyfunctional amine polymer having from about
20 percent to about 100 percent of the monomer units by weight
containing an amine or imine group; and
(c) an amount of volatile base sufficient to raise the pH of the
composition to a point where essentially all of the polyfunctional
amine polymer is in a non-ionic state a test film of said
composition having a dry time of 10 minutes as determined under a
modified ASTM D1640 dry
test..Iaddend..Iadd.25. A shelf stable fast cure aqueous traffic
paint consisting essentially of:
(a) an anionically stabilized emulsion polymer having a Tg greater
than about 0.degree. C.;
(b) a water soluble polyfunctional amine polymer having from about
20 percent to about 100 percent of the monomer units by weight
containing an amine or imine group; and
(c) an amount of volatile base sufficient to raise the pH of the
composition to a point where essentially all of the polyfunctional
amine polymer is in a non-ionic state, a test film of said
composition having a dry time of 10 minutes as determined under a
modified ASTM D1640 dry test..Iaddend..Iadd.26. A shelf stable fast
cure aqueous composition consisting essentially of:
(a)an anionically stabilized emulsion polymer having a Tg greater
than about 0.degree. C.;
(b) a water soluble polyfunctional amine polymer polymerized from
monomer units containing an imine group; and
(c) an amount of volatile base sufficient to raise the pH of the
composition to a point where essentially all of the polyfunctional
amine
polymer is in a non-ionic state..Iaddend..Iadd.27. A shelf stable
fast cure aqueous traffic paint consisting essentially of:
(a) an anionically stabilized emulsion polymer having a Tg greater
than about 0.degree. C.;
(b) a water soluble polyfunctional amine polymer polymerized from
monomer units containing an imine group; and
(c) an amount of volatile base sufficient to raise the pH of the
composition to a point where essentially all of the polyfunctional
amine polymer is in a non-ionic state..Iaddend.
Description
BACKGROUND OF THE INVENTION
This invention relates to aqueous coatings, particularly aqueous
road-marking paint that dries quickly after application.
Various attempts to produce an aqueous road-marking paint as a
substitute for solvent-based road marking paints have been
disclosed in the art. A significant problem has been that the
aqueous paints do not dry quickly enough.
European Patent Application No. 200249 discloses applying an
aqueous dispersion of polymer to the road and then contacting the
composition with a water soluble salt to cause the coating to dry
rapidly and resist washout by a rain shower five minutes after
application. This disclosure would require spraying with two
compositions which would require the use of extra equipment.
European Patent application 0 066 108 discloses an aqueous road
marking composition in which the binder is a mixture of a pure
acrylic resin, a carboxylated styrene/dibutyl fumarate copolymer
and a polymeric, polyfunctional amine such as polypropylenimine.
This application states that the disclosed compositions arc not
storage stable beyond 48 hours after which more polyfunctional
amine must be added to restore activity.
SUMMARY OF THE INVENTION
The present invention provides a coating composition that dries
quickly, develops water resistance soon after application and
retains reactivity after storage.
The aqueous coating composition contains anionically stabilized
emulsion polymer having a Tg greater than about 0.degree. C. an
effective amount of polyfunctional amine and a volatile base in an
amount effective to raise the pH of the composition to a point high
enough for the polyfunctional amine to be essentially in a
non-ionized state (deprolonation) thereby eliminating polyamine
interaction with the anionically stabilized emulsion and anionic
ingredients in the coating.
In one aspect the invention provides an aqueous road or
pavement-marking paint. The aqueous road or pavement marking paint
of the invention can be used to mark lines or symbols on roads,
parking lots walkways. etc. of various compositions such as
asphaltic, bituminous or concrete paving with or without aggregate
filler or top-dressing. This aqueous road-marking paint dries
quickly, to develop early resistance to washout and tire tread
printing.
DETAILED DESCRIPTION OF THE INVENTION
The aqueous coating composition is made from:
(A) an anionically stabilized polymer latex;
(B) a soluble or dispersible, preferably a soluble, polymer
produced from monomer units in which from about 20% to 100% by
weight of the monomer units contain an amine group;
(C) a volatile base in an amount effective to raise the pH of the
composition to a point high enough for the polyfunctional amine to
be essentially in a non-ionized state (deprotonation) thereby
eliminating polyamine interaction with the anionically stabilized
emulsion and anionic ingredients in the coating. The volatile base
must be volatile enough to be released under air dry
conditions.
Anioinically Stabilized Polymer
The anionically stabilized emulsion polymer can be prepared by
known procedures, which arc published in texts on the subject such
as "Emulsion Polymerization: Theory and Practice" by D. C. Blackley
published by Wiley in 1975 and "Emulsion Polymerization" by F. A.
Bovey et al. published by Interscience Publishers in 1965. In
general, the anionically stabilized latex polymer is a polymer or
copolymer prepared from monomers such as methyl acrylate, ethyl
acrylate, butyl acrylate, 2-ethylhexyl acrylate, decyl acryate,
methyl methacrylate, ethyl methacrylate, butyl methacrylate,
styrene, butadiene, ethylene, vinyl acetate, vinyl ester of
"Versatic" acid (a tertiary monocarboxylic acid having C.sub.9,
C.sub.10 and C.sub.11 chain length, the vinyl ester is also known
as "vinyl versatate"), vinyl chloride, vinyl pyridine, vinylidene
chloride, acrylonitrile, chloroprene, acrylic acid, methacrylic
acid, itaconic acid, maleic acid and fumaric acid. Polymers and
copolymers of alpha-beta ethylenically unsaturated monomers and
their esters, especially the acrylic and methacrylic esters, arc
preferred and are preferably prepared by processes given in
"Emulsion Polymerization of Acrylic Monomers: May, 1966" published
by the Rohm and Haas Company, Philadelphia, Pa., incorporated
herein by reference.
The negative charge on the dispersed latex particles is obtained in
any of several ways, the most common being the use of anionic
surfactants or dispersants as the stabilizer during the emulsion
polymerization or added to the emulsion after polymerization.
Nonionic surfactants may, of course, also be present in the latex
during or after polymerization of these anionically stabilized
latexes. Among the useful surfactants and dispersants arc the salts
of fatty rosin and naphthenic acids, condensation products of
napthalene sulfonic acid and formaldehyde of low molecular weight,
carboxylic polymers and copolymers of the appropriate
hydrophile-lipophile balance, higher alkyl sulfates, such as sodium
lauryl sulfate, alkyl aryl sulfonates, such as dodecylbenzene
sulfonate, sodium or potassium isopropylbenzene sulfonates or
isopropylnaphthalene sulfonates; sulfosuccinates, such as sodium
dioctylsulfosuccinate alkali metal higher alkyl sulfosuccinates.
e.g. sodium octyl sulfosuccinate, sodium
N-methyl-N-palmitoyltaurate, sodium olcyl isethionate, alkali metal
salts of alkylarylpolyethoxycthanol sulfates or sulfonates, e.g.
sodium t-octylphenoxy-polyethoxyethyl sulfate having 1 to 5
oxyethylene units, and the various other anionic surfactants and
dispersants well-known in the art.
Another type of negatively-charged latex is that which is obtained
as a result of including in the polymers small amounts of acidic
groups, which may be in the salt form, such as an alkali metal or
ammonium salt. Examples of such acidic groups are those derived
from incorporated initiator fragments, maleic acid, vinyl sulfonic
acid, crotonic acid, acrylic acid, methacrylic acid, iraconic acid,
and the like.
The polymer must have a glass transition temperature (Tg) above
0.degree. C. Polymers having a Tg below 0.degree. C. are generally
not useful since they are too soft, resulting in poor scrub
resistance and accelerated dirt pickup. The invention may also be
practiced using polymers of more complex morphology, such as
core-shell particles. These complex polymer morphologies usually
display multiple Tg's and may display a Tg value below 0 degrees C.
as one of its multiple Tg's, however the average or effective Tg of
the polymer must be above about 0 degrees C.
To prepare a storage stable composition of the amine-containing
polymer and the anionically stabilized emulsion polymer, the
amine-functional polymer is maintained essentially in a nonionic
state by adding a sufficient amount of volatile base to raise the
pH of the composition at or near the point at which substantially
all the amine functional groups are in a nonionic state
(deprotonation) and therefore do not interact with the anionically
stabilized latex. A starting point estimate of the amount of
volatile base required to reach this point can be calculated from
the number of equivalents of base needed to neutralize all of the
acid groups in the latex (i.e. acid groups from: copolymerized
carboxylic-bearing monomer; surfactant; or initiator) and the
conjugate acid of the amine base. If the amine is not sufficiently
deprotonated, the emulsion will exhibit observeable signs of
instability over time, such as viscosity increase and
microscopically observeable "particle rafting", an early stage of
aggregation/gellation. One equivalent of volatile base (based on
latex acids and polyamine titers) is usually enough to yield a
stable system although higher levels of volatile base (.about.3 to
4 equivalents) may be necessary for long term stability. Higher
amounts of volatile base can be used without departing from the
spirit of the invention although the "quick dry" properties of the
coating may be reduced. If the equipment used in the process of
manufacture presents opportunities for loss of the volatile base by
evaporation at any stage from when the volatile base is added until
after the product is packaged in a sealed container, the amount of
volatile amine loaded to the production equipment should be
increased to offset the loss.
After application, the volatile base evaporates thus lowering the
pH of the composition. When the pH of the composition falls to a
point where the protonation of the polyamine begins to occur, the
polyamine becomes cationic. The quick dry is believed to be
initiated by this conversion of the polyamine to a cationic polymer
in the presence of the anionically stabilized emulsion polymer,
although the exact mechanism that produces the quick-dry property
has not been established.
Polyfunctional Amine
The compositions of this invention contain a polyfunctional amine,
preferably a polymer containing from about 20% to 100%, and
preferably at least 50% by weight of amine-containing monomer.
Examples of the amine containing monomers include members of the
following classes:
Amine Classes
1. Aminoalkyl vinyl ethers or sulfides wherein the alkyl groups may
be straight-chain or branched-chain type and have from two to three
carbon atoms and wherein the nitrogen atom may be a primary,
secondary, or tertiary nitrogen atom (U.S. Pat. No. 2,879,178). In
the latter instance, one of the remaining hydrogen atoms may be
substituted by alkyl, hydroxyalkyl, or alkoxyalkyl groups, the
alkyl components of which may have one to four carbon atoms,
preferably one carbon atom only. Specific examples include:
beta-aminoethyl vinyl ether; beta-aminoethyl vinyl sulfide;
N-monomethyl-beta-aminoethyl vinyl ether or sulfide; N-monoethyl-
beta -aminoethyl vinyl ether or sulfide; N-monobutyl- beta
-aminoethyl vinyl ether or sulfide; and N-monomethyl-3-aminopropyl
vinyl ether or sulfide.
2. Acrylamide or acrylic esters, such as those of the formula II:
##STR1## wherein R is H or CH.sub.3 ;
n is 0 or 1;
X is O or N(H);
When n is zero, A is O(CH2).sub.x wherein x is 2 to 3, or
(O-alkylene).sub.y wherein (O-alkylene).sub.y is a
poly(oxyalkylene) group, having a molecular weight in the range
from 88 to 348, in which the individual alkylene radicals are the
same or different and are either ethylene or propylene; and
when n is I, A is an alkylene group having two to 4 carbon
atoms;
R* is H, methyl, or ethyl; and
R.sup.1 IS H, methyl, or ethyl; and
R.sup.0 is H, phenyl, benzyl, methylbenzyl, cyclohexyl, or (C.sub.1
-C.sub.6) alkyl.
Examples of compounds of formula II include:
dimethylaminoethylacrylate or methacrylate; beta -aminoethyl
acrylate or methacrylate; N- beta-aminoethyl acrylamide or
methacrylamide; N-(monomethylaminoethyl)-acrylamide or
methacrylamide; N-(mono-n-butyl)-4-aminobutyl acrylate or
methacrylate; methacryloxyethoxyethylamine; and
acryloxypropoxypropoxypropylamine.
3. N-acryloxyalkyl-oxazolidines and
N-acryloxyalkyltetrahydro-1,3-oxazines and the corresponding
components in which the "alkyl" linkage is replaced by alkoxyalkyl
and poly(alkoxy-alkyl), all of which are embraced by Formula III:
##STR2## wherein R is H or CH.sub.3 ;
m is an integer having a value of 2 to 3;
R', when not directly joined to R.sup.2, is selected from the group
consisting of hydrogen, phenyl, benzyl, and (C.sub.1 -C.sub.12)
alkyl groups;
R.sup.2, when not directly joined to R', is selected from the group
consisting of hydrogen and (C.sub.1 -C.sub.4) alkyl groups; R' and
R.sup.2, when directly joined together, form a 5- to 6-carbon ring
with the attached carbon atom of the ring in the formula. i.e., R'
and R.sup.2, when joined together, are selected from the group
consisting of pentamethylene and tetramethylene; and
A' is O(C.sub.m H.sub.2m)-- or (O-alkylene).sub.n in which
(O-alkylene).sub.n is a poly(oxyalkylene) group, having a molecular
weight in the range from 88 to 348, in which the individual
alkylene radicals are the same or different and are either ethylene
or propylene.
The compounds of Formula III can hydrolyze under various conditions
to secondary amines. The hydrolysis produces products having the
Formula IV: ##STR3##
The compounds of Formula III are disclosed in U.S. Pat. Nos.
3,037,006 and 3,502,627 in the hands of a common assignee, and
their corresponding foreign applications and patents and any of the
monomeric compounds disclosed therein may be used in making the
copolymers to be used in the composition of the present
invention.
Examples of compounds of Formula III include:
oxazolidinylethyl methacrylate; oxazolidinylethyl acrylate;
3-(gamma-methacryl-oxypropyl)-tetrahydro- 1,3-oxazine; 3-(beta
-methacryloxyethyl)-2,2-penta-methylene-oxazolidine;
3-(beta-methacryloxyethyl-2-methyl-2-propyloxazolidine;
N-2-(2-acryloxyethoxy)ethyl-oxazolidine;
N-2-(2-methacryloxyethoxy)ethyloxazolidine;
N-2-(2-methacryloxyethoxy)ethyl-5-methyl-oxazolidine;
N-2-(2-acryloxycthoxy)ethyl-5-methyl-oxazolidine;
3-[2-(2-methacryloxyethoxy)
ethyl)]-2,2-penta-methylene-oxazolidine;
3-[2-(2-methacryloxyethoxy)ethyl)]-2,2-dimethyloxazolidine;
3-[2-(methacryloxyethoxy)ethyl]-2-phenyl-oxazolidine.
4. Polymers of monomers which readily generate amines by hydrolysis
are useful as the amine;containing component or to generate the
amine-containing component polymer of this binder composition.
Examples of such monomers are acryloxy-ketimines and -aldimines,
such as those of Formulas V and VI following:
wherein
R is H or CH.sub.3 ;
Q is selected from the group consisting of ##STR4## R.sup.6 is H or
it may be methyl in one CHR.sup.6 unit; R.sup.5 is selected from
the group consisting of (C.sub.1 -C.sub.12)-alkyl and cyclohexyl
groups;
R.sup.4 is selected from the group consisting of (C.sub.1
-C.sub.12)-alkyl and cyclohexyl
R.sup.3 is selected from the group consisting of phenyl,
halophenyl.
(C.sub.1 -C.sub.12)-alkyl, cyclohexyl, and (C.sub.1 -C.sub.14)
alkoxyphenyl groups;
A" is a (C.sub.1 -C.sub.12) alkylene group;
A.sup.o, B and D arc the same or different oxyalkylene groups
having the formula --OCH(R.sup.7)--CH(R.sup.7)--wherein R.sup.7 is
H, CH.sub.3, or C.sub.2 H.sub.5 ;
x is an integer having a value of 4 to 5;
n.sup.o is an integer having a value of 1 to 200;
n' is an integer having a value of 1 to 200; and
n" is an integer having a value of 1 to 200, the sum of n.sup.o -1,
n'-1 and n"-1 having a value of 2 to 200.
Illustrative compounds of formulas V and VI are:
2-[4-(2,6-dimethylheptylidene)-amino]-ethyl methacrylate
3-[2-(4-methylpentylidine)-amino]-propyl methacrylate
beta-(benzylideneamino)-ethyl methacrylate
3-[2-(4-methylpentylidine)-amino]-ethyl methacrylate
2-[4-(2,6-dimethylheptylidene)-amino]-ethyl acrylate
12-(cyclopentylidene-amino)-dodecyl methacrylate
N-(1,3-dimethylbutylidene)-2-(2-methacryloxyethoxy)-ethylamine
N-(benzylidene)-methacryloxyethoxyethylamine
N-(1,3-dimethylbutylidene)-2-(2-acryloxyethoxy)-ethylamine
N-(benzylidene)-2-(2-acryloxyethoxy)ethylamine
The compounds of Formulas V and VI hydrolyze in acid, neutral, or
alkaline aqueous media to produce the corresponding primary amines
or salts thereof in which the group --N.dbd.Q of the formulas
becomes --NH.sub.2 and O.dbd.Q. The compounds of Formulas V and VI
are disclosed in U.S. Pat. Nos. 3,037,969 and 3,497,485, and any of
the monomeric compounds therein disclosed may be used in the making
of the copolymers to be used in the water-soluble polymer portion
of the compositions of the present invention.
Description of Polymer Solubility
Water-soluble amine-containing polymers include both the completely
soluble and the partly soluble polymers. The term water-soluble
amine-containing polymer describes polymer that is completely
soluble either in free-base, neutral, or salt form. Some polymers
are soluble at all pH's, while others are soluble over a range of
pH for example from about 5 to 10. Other amine-containing polymers
are generally insoluble at high pH and soluble or partly soluble at
acidic pH values, particularly in the pH range from about 5 to
about 7. By partly soluble is meant both the situation in which
some of the polymer is soluble in water as well as that in which
the entire polymer dissolves in the form of micelles or aggregates
of individual molecules, generally, highly water swollen
aggregates. The latter are often called colloidal solutions. It is
preferred that most of the polymer be soluble at the acidic pH
values.
Amine Polymer Preparation
In general, the amine-containing polymers may be obtained by
solution polymerization in aqueous media, either neutral, alkaline,
or acidic, depending upon the particular polymer sought, as
generally known in the art, for example as taught in U.S. Pat. No.
4,119,600. Generally, the polymerization is carried out in an
aqueous medium containing a small amount of an acid, either organic
or inorganic, such as acetic acid or hydrochloric acid. The
amine-containing polymers include copolymers with up to 80% by
weight one or more monoethylenically unsaturated monomers, such as
methyl acrylate, acrylamide and methacrylamide. Small amounts of
relatively insoluble comonomers may also be used to obtain the
water-soluble polymers. The insoluble polymers may contain larger
amounts of these comonomers. Such monomers include, as examples,
acrylic acid esters with (C1 to C18) alcohols and methacrylic acid
esters with alcohols having one to 18 carbon atoms, especially
(C1-C4) alkanols; styrene, vinyltoluene, vinyl acetate, vinyl
chloride, vinylidene chloride, substituted styrenes, butadiene,
substituted butadienes, ethylene; and the nitrites and amides of
acrylic or of methacrylic acid. The particular comonomer or
comonomers used in making a given amine-containing polymer depends
upon the proportion of amine-containing monomer used in making the
copolymer. The polymers arc thus polymers or copolymers of cationic
and, optionally, nonionic vinyl monomers. Examples of the cationic
monomers are the amines and imines; the other recited monomers arc
nonionic. Thus, these water-soluble copolymers contain no acid
groups other than trace amounts which may be present due to
impurities in the monomers used or to small extent of hydrolysis
during synthesis, storage or use.
Volatile Base
The type and amount of volatile base used must be sufficient to
raise the pH of the composition to about the point where the
polyfunctional amine is non-ionized (deprotonated), to avoid
interaction with the anionically stabilized emulsion. The volatile
base of preference is ammonia, which may be used as the sole
volatile base or in admixture with other volatile or nonvolatile
bases. Other volatile bases which may be employed are morpholine,
the lower alkyl amines, 2-dimethylaminoethanol, N-methylmorpholine,
ethylenediamine, and others.
Filler, extenders, pigments and other additives known in the art
may also be used in the compositions of the invention. If pigment
is used in the traffic paint composition, it is typically in the
range of fifty percent pigment volume content to sixty percent
pigment volume content. Examples of pigments that may be employed
include clays, calcium carbonate, talc, titanium dioxide, carbon
black, and various colored pigments.
Care must be exercised when selecting the type and amount of
additives to avoid altering the pH of the composition to an extent
that interferes with storage stability or buffering the pH to an
extent that after application the pH does not fall sufficiently to
initiate protonation of the polyamine. For example a paint prepared
using a polyamine with a relatively low pKa and too large an amount
of calcium carbonate as filler, may display an unacceptably
extended cure time.
Traffic paint compositions typically have a solids content in the
range of from thirty five% to seventy% by volume and a viscosity of
from about 70 kreb units to about 100 kreb units, Coatings provided
by the invention are also useful in other exterior coatings such as
maintenance coatings, house paint, etc..
The following examples illustrate some aspects of the invention and
should not be construed as limiting the scope of the invention
which is described in the specification and claims.
Abbreviations:
AM=Acrylamide
DMAEMA=Dimethylaminoethylmethacrylate
DMAPMA=Dimethylaminopropylmethacrylamide
HEMA=Hydroxyethylmethacrylate
MMA=Methylmethacrylate
OXEMA=Oxazolidinoethylmethacrylate
p-OXEMA=poly-oxazolidinoethylmethacrylate
Paint Preparation
The test paints were prepared according to the following standard
paint formulation by grinding together the ingredients listed as
grind ingredients below and then adding the remaining ingredients
in the letdown. The emulsion was an anionic copolymer of butyl
acrylate, methyl methacrylate and methacrylic acid having a T.sub.g
of 20.degree. C., and a particle size of 200 nanometers.
______________________________________ Grind ingredient Amount
(lb/103 gals) ______________________________________ Emulsion (50%
solids) 457.9 Water 28.4 Tamol 850 7.1 Triton CF-10 2.8 Drew L-493
1.0 TiPure R900 100.0 Silverbond B 156.3 Snowflake-(calcium
carbonate) 595.9 LetDown Texanol 22.9 Methanol 15.0 Drew L-493 2.0
Hydroxyethyl cellulose 250 MR 15.0 (2.5% solotion in water) 1,403.3
______________________________________
DESCRIPTION OF TEST METHODS
Dry Time Test
This test is similar to ASTM D1640 which is a standard test for
drying of organic coatings at room temperature. The test films are
applied on a non-porous substrate (glass plate or metal panel) by
suitable means to give a wet film thickness of 0.012+/-0.001
inches. The ASTM test method is modified in that only minimal thumb
pressure is used. The thumb is turned through an angle of
90.degree. while in contact with the film. The drying time at which
this rotation does not break the film is recorded.
Early Washout Resistance
The test films are prepared in the same manner as for the dry time
test. After the films have dried for 15 minutes at a temperature of
78.degree. F and 50% relative humidity, the samples were held under
a stream of cold running water (tap pressure of 170-200 gallons per
hour), which contacted the surface of the paint film at from a
nearly perpendicular to an oblique angle. The samples remained
under the stream of running water for a period of five (5) minutes.
At the end of this period the samples were removed from the test
stream and rated by visual inspection. Samples that showed no
apparent effect were rated passes; those that exhibited slight
disruption of the film were rated marginal; those samples that
showed a break in the film or any film removal were rated as
fails.
Scrub Resistance
Films of 3.5 mils dry thickness were prepared and cured for 24
hours at 77.degree. F. +/-2.degree. F. and 40-55% relative
humidity. The films were tested according to according to ASTM
D2486. The number of scrub cycles at which to an area of the paint
film was fully removed was recorded.
Heat Aging Test
One pint of the test paint was placed in a sealed can and stored in
a sealed circulation oven at 120.degree. F. for one week. The can
was removed from the oven and the paint was observed. If the paint
is still fluid and shows no apparent signs of bodying or separation
it is rated as a pass.
EXAMPLES
Comparative Example A--Addition of Polyamine to Anionic Polymer
Latex Produces Paint That Is Not Storage Stable
To a paint formulation prepared according to the formulation
described above, 10 lbs. of polyOXEMA (28.5% solids) was added. The
consistency of this paint changed from a fluid mixture to a
solidified mass on aging 16 hours at ambient temperature.
Example 1--Addition of Volatile Base Produces Paint That Is Storage
Stable
The procedure of the Comparative Example was repeated except that
3.9 lbs. of ammonium hydroxide (28%) was added before the
polyOXEMA. The paint remained fluid when stored at room temperature
and passed the heat aging test.
Example 2--Various Levels of Polyamine
Test paints were prepared by adding polyamine (polyOXEMA), as in
Example 1, in the amount indicated in the table as a percent by
weight based on vehicle solids. The paints were applied to
substrates and tested. The standard paint without any
amine-containing polymer was used as a control. The results appear
in the table below:
______________________________________ Level of Polyamine Scrub (%
solids on Easy Washout Resistance vehicle solids) Resistance
Properties ______________________________________ Control fail 950
cycle 0.27% p.OXEMA marginal -- 0.62% p.OXEMA passes 760 cycles
1.25% p.OXEMA passes 950 cycles 2.5% p.OXEMA passes 910 cycles
______________________________________
The above data demonstrates that the amine-functional polymer
produces early washout resistance with acceptable scrub resistance
properties. Also, the paint containing 1.25% polyOXEMA dried in 10
minutes in the dry time test compared to 20 minutes dry time for
the Control paint that doesn't contain polyamine.
Example 3--Use of Polymers and Copolymers of Various
Amine-containing Monomers Demonstrated
Paints were prepared using the indicated amine-containing polymer
according to the procedure of Example 1. The paint without any
amine-containing polymer was used as a control. Samples were
prepared by adding amine-containing polymer to the standard
formulation in the amount indicated in the table measured as a
percent by weight based on vehicle solids. The sample emulsions
were applied to substrates and tested. The results appear in the
table below:
______________________________________ Type of Polyamine in marking
point Early Washout 7 days aging Formulation (1.25% S/S) Resistance
120.degree. F. ______________________________________ none fail
passes pOXEMA passes passes OXEMA/HEMA 50/50 passes passes
OXEMA/MMA 70/30 passes passes DMAPMA/AM 70/30 passes passes
DMAPMA/HEMA 70/30 passes passes (0.44% s/s) pDMAEMA passes passes
______________________________________
The above data demonstrates that marking paints according to the
invention have early washout resistance and were storage stable
even under storage at elevated temperature.
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