Note: Descriptions are shown in the official language in which they were submitted.
1~a74~
Field of the Invention
This invention relates to aqueous disperse compositions
capable of irreversibly forming coherent films. More particularly,
it relates to compositions comprising as an internal phase at
least one film-forming, non-asphaltic, olea~inous material and
an external phase comprising a clay thickened water slurry
wherein the slurry also contains at least one flocculating agent.
Processes for makin~ such compositions, coherent films produced
from them and articles of manufacture wherein a metallic surface ~
10 is at least partially coated with such films are part of the ~;
invention. Methods of inhibiting corrosion of metal surfaces
using these compositions are also within the scope of the ;~
invention.
_rior Art
Both oil-based and water-based clay-thickened
compositions are known. See, for example, U.S. Patents 3,763,042; ;
3,449,248; 3,250,735; and 3,247,011.
Overbased non-Newtonian colloidal disperse systems are
also known. See, for example, U.S. Patents 3,384,586;
3,24~,079; 3,372,114; 3,372,115; 3,376,222; 3,377,283; 3,422,013;
and 3,49~,231.
Other U.S. patents describing such non-Newtonian
systems include the followin~: 3,746,643; 3,816,310; 3,746,643;
and 3,671,012.
Clay-thickened, aqueous asphalt emulsions are known to
the art. See, for example, U.S. Patents 3,095,339; 2,652,341;
and 1,398,201. Asphalt emulsions containing sulfonic acid
salts are also known. See U.S. Patent 2,503,246.
- 1 -
: , . :~ . ::
. : , ~ :
It is an object of this invention to provide aqueous
disperse compositions capable o~ irreversibly forming coherent
Eilms.
It is also an object of this invention to provide
methods of making such aqueous disperse compositions.
A further object of this invention is to provide
coherent films made by removal of a substantial proportion of
water from these aqueous disperse compositions.
It is also an object of this invention to provide
methods for inhibiting corrosion of metal surfaces by applying
such disperse compositions to a metal surface and removing a
substantial proportion of water to form a coating or film~
Other objects of the invention will be apparent to those
skilled in the art upon study oE this specification.
The present invention provides an aqueous disperse
composition, capable of irreversibly forming a coherent film,
comprising (I) an internal phase comprising at least one film-
forming, non-asphaltic, oleaginous material (A) which is a
carboxylate salt made by reacting at least one carboxylic acid
(D), or reactive equivalent thereof, with at least one non-
Newtonian system (~) comprising an overbased salt of an organic
acid, and (II) an external phase comprising a clay-thickened
water slurry (s-l) having a pH in the range of about 6 to about 9,
said slurry containing, in addition to water and at least one
clay (B-2), at least one flocculating agent (C). Methods for
preparing such aqueous disperse compositions as well as films
formed by the removal of a substantial proportion of water from
the composition are also within the scope of the invention, as
are articles of manufacture
/i ~
~74~
having at least one metal surface of which at least a por-
tion is covered by such films and methods of inhibiting
corrosion of metallic surfaces by the use of such composi-
tions.
The term "coherent" is used herein to indicate that
films formed by the practice of this invention hold together
firmly with stickiness and resist separation including
separation from the substrate they may cover. As those
skilled in the art are aware, such coherent films are ;~
particularly useful in many applications such as coating
metal surfaces to inhibit corrosion and/or wear.
The terms "external" and "internal" phases are used
herein in their art-recognized sense to signify the dis~
continuous and continuous phases, respectively, of an
emulsion.
The film-forming, non-asphaltic, oleaginous materials
(~ used in this invention typically comprise carboxylate
salts and oil solutions/dispersions of such carboxylate
salts. Organic resins with acid functionality which is
capable of reacting with carbonates and bicarbonates to form
carbon dioxide can also be used. Such functional groups as
sulfonic, phosphoric, sulfuric, and boric acid groups are of
this type. The fact that these materials are non-asphaltic
in nature makes them preferable to asphaltic materials
because of environmental and other co~cerns. Typical
carboxylate salts are made by reactin~ (D) at least one
carboxylic acid, or reactive equivalent thereof such as an
anhydride, with (E~ at least one overbased salt of an
organic acid, usually one that has been converted into a
non-Newtonian colloidal disperse system. The carboxylic
:
~7~
a~id (D) can be formed by oxidation of petroleum fractions such
as petroleum wax fractlons. Carboxylic acids of the general
formula
R(COOH)X Formula (I)
wherein R is a substantially hydrocarbyl group of about 12 to about
300 carbon atoms derived from polymerization of at least one C2_8
olefin and x is 1,2, or 3 can also be used as can mixtures of such
acids with the aforementioned oxidized waxes. The acids of Formula
I can be made by reacting an olefin (e.g., a polyalkylene such as
polybutene, polypropylene, etc.) or derivative thereof ~e.g., a
halogenated derivative) with a lower molecular weight unsaturated
carboxylic acid or derivative thereof. Typical such unsaturated
carboxylic acids (and derivatives) include acylic acid,
methacrylic acid, maleic acid, maleic anhydride, fumaric acid,
and the like. Many patents describe the production of the acids
of Formula I including, for example, the following United States,
British and Canadian Patents: U.S. Patents 3,024,237; 3,087,936;
3,172,892; 3,215,707; 3,219,666; 3,~31,587; 3,245,910; 3,272,746;
3,288,714; 3,312,613; 3,341,542; 3,367,943; 3,381,022; 3,454,607;
3,470,098; 3,630,902; 3,652,616; 3,755,169; 3,868,330; 3,912,764;
U.K. Patents 944,136; 1,085,903; 1,162,436; 1,440,219; and
Canadian Patent 956,397.
More typically, for reasons of economy and availability,
the carboxylic acid ~D) used in making the film-forming
materials used in the present invention is made by
-- 4
,
, ~ . ~
:
~C! 97~
oxidation of a petroleum wax fraction. While various kinds
of wax, such as paraffinic, microcrystalline, and slack
waxes can be used, a particularly suitable wax has been
found to be petrolatum.
Oxidation of these materials can be accomplished by
many techniques known to those of skill in the art. Usually
such oxidations are carried out by blowing air through the
wax in the presence of a metal catalyst such as a copper,
cobalt or manganese salt. Further details concerning wax
oxidations can be found in "Chemistry of Petroleum Deriva-
tives" by Karelton Ellis, particularly pages 962-979
Rhinehold Publishing Corporation, New ~ork (1937).
A particularly suitable oxidized petrolatum for use in
making the film-forming oleaginous materials (A) used in the
present invention is available from the Ashland Oil Company
under thè~name of Tectyl 3050. Other available oxidized
petrolatum fractions are available from the petroleum
industry and can be used alone or in admixture with the
aforementioned Tec~yl 3050.
The film-forming, non-asphaltic oleaginous material (A~
used in making the disperse compositions of this invention
are typically made by reacting at least one of the afore-
descri~ed carboxylic acidsl(D) with at least one overbased
salt of an organic acid (E); o~viously, mixtures of over-
based salts ~Ej can be used.
These overbased salts of organic acids are widely known
to those of skill in the art and generally include metal
salts wherein the amount of metal present in them exceeds
the stoichiometric amount. Such salts are said to have
conversion levels in e~cess of 100~ (i.e., they comprise
-- 5 --
~ a7~0
more than 100% of the theoretical amount of metal needed to
convert the acid to its "normal", "neutral" salt). Such
salts are often said to have metal ratios in excess of one
(i.e., the ratio of equivalents of metal to equivalents of
organic acid present in the salt is greater than that
required to provide the normal or neutral salt which re~uires
only a stoichiometric ratio of 1:1). They are commonly
referred to as overbased, hyperbased or superbased salts and
are usually salts of organic sulfur acids, organic phos-
phorus acids, carboxylic acids, phenols or mixtures of two
or more of any of these. As a skilled worker would realize,
mixtures of such overbased salts can also be used. ;~
The terminology "metal ratio" is used in the prior art
and herein to deslgnate the ratio of the total chemical
equivalents of the metal in the overbased salt to the
chemical equivalents of the metal in the salt which would be
expected to result in the reaction between the organic acid
to be overbased and the basically reacting metal compound
according to the known chemical reactivity and stoichiometry
2~ of the two reactants. Thus, in a normal or neutral salt the
metal ratio is one and in an overbased salt the metal ratio
is greater than one,
The overbased salts used as (Ei in this invention
usually have metal ratios of at least about 3:1. Typically,
they have ratios of at least about 12:1. Usually they have
metal ratios not sxceeding about 40:1. Typically salts
having ratios of about 12:1 to about 20:1 are used.
The basically reacting metal compounds used to make
these overbased salts are usually an alkali or alkaline
earth metal compound (i.e., the Group I~, IIA, and II~
-- 6 --
7~
metals excluding francium and radium and typically excluding
rubidium, cesium, and beryllium) although other basically
reacting metal compounds can be used. Basically reacting
compounds of Ca, Ba, Mg, Na, and Li, such as their hydrox-
ides and alkoxides of lower alkanols are usually used as the
basically reacting metal compounds in preparing these
overbased salts but others can be used as shown by the prior
art incorporated by reference herein. Overbased salts
containing a mixture of ions of two or more of these metals
can be used in the present invention.
These overbased salts can be of oil-soluble organic
sulfur acids such as sulfonic, sulfamic, thiosulfonic,
sulfinic, sulfenic, partial ester sulfuric, sulfurous and
thiosulfuric acid. Generally they are salts oE carbocyclic
or aliphatic sulfonic acids.
The carbocyclic sulfonic acid~ include the mono- or
poly-nuclear aromatic or cycloaliphatic compounds. The oil-
soluble sulfonates can be represented for the most part by
the following formulae:
[Rx- T -tSO3)y]zMb Formula II
[R'--(So3~a3dMb Formula III
In the above formulae, M is either a metal cation as des-
cribed hereinabove or hydrogen; T is a cyclic nucleus such
as, for example, benzene, naphthalene, anthracene, phenan-
threne, diphenylene oxide, thianthrene, phenothioxine,
diphenylene sulfide, phenothiazine, diphenyl oxide, diphenyl
sulfide, diphenylamine, cyclohexane, petroleum naphthenes,
decahydro-naphthalene, cyclopentane, etc.; R in Formula II
is an aliphatic group such as alkyl, alkenyl, alkoxy,
alkoxyalkyl, carboalkoxyalkyl, e~c.; x is at least 1, and Rx
- 7 -
:
~7~
+ T contains a total o~ at least about 15 carbon atoms. R'
in Formula III is an aliphatic radical containing at least
about 15 carbon atoms and M is either a metal cation or
hydrogen. Examples of types of the R' radical are alkyl,
alkenyl, alkoxyalkyl, carboalkoxyalkyl, etc. Specific
examples of R' are groups derived from petrolatum, saturated
and unsaturated paraffin wax, and polyolefins, including
polymerized C2, C3~ C4, Cs- C6, etc., olefins containing
from about 15 to 7000 or more carbon atoms. The groups T,
R, and R' in the abo~e formulae can also contain other
inorganic or organic substituents in addition to those
enumerated above such as, for example, hydroxy, mercapto,
halogen, nitro, amino, nitroso, sulfide, disulfide, etc. In
Formula II, x, y, z and b are at least lr and likewise in
Formula III, a, b and d are at least 1.
Specific examples of sulfonic acids useful in this
invention are mahogany sulfonic acids; bright stock sulfonic
acids; sulfonic acids derived from lubricating oil fractions
having a Saybolt viscosity from about 10~ seconds at lOO~F.
to about 200 seconds at 210F ; petrolatum sulfonlc acids;
mono- and poly-wax substituted sulfonic and polysulonic
acids of, e.g., benzene, naphthalene, phenol, diphenyl
ether, naphthalene disulfide, diphenylamine, thiophene,
alpha-chloronaphthalenel etc.; other substituted sulfonic
acids such as alk~rl benzene sulfonic acids (where the alkyl
group has at least 8 carbons), cetylphenol mono-sulfide
sulfonic acids, dicetyl thianthrene disulfonic acids, di-
lauryl beta naphthyl sulfonic acids, dicapryl nitronaphtha-
lene sulfonic acids, and alkaryl sulfonic acids such as
dodecyl benzene "bottoms" sulfonic acids.
~7~
The latter are acids der~ved from benzene which has
been alkylated with propylene tetramers or isobutene trimers
to introduce 1, 2, 3, or more branched-chain C12 substituents
on the benzene ring. Dodecyl benzene bottoms, principally
mixtures of mono- and di-dodecyl benzenes, are available as
by-products from the manufacture of household detergents.
Similar products obtained from alkylation bottoms formed during
manufacture of linear alkyl sulfonates (LAS~ are also useful
in making the sulfonates used in this invention.
The production of sulfonates from detergent manufacture
by-products by reaction with, e.g. SO3, is well known to those
s~illed in the art. See, for example, the article "Sulfonates"
in Kirk-Othmer "Encyclopedia of Chemical Technology", Second
Edition, Vol. 19, pp. 291 et seq. published by John Wiley & Sons,
N.Y. (1969).
Other descriptions of overbased sulfonate salts and
techniques for making them can be found in the following U.S.
Patents: 2,174,110; 2,174,506; 2,174,508; 2,193,824; 2,197,800;
2,202,781; 2,212,786; 2,213,360; 2,228,598; 2,233,676; 2,239,974;
; 20 2,263,312; 2,276,090; 2,276,097; 2,315,514; 2,319,121; 2,321,022;
2,333,568; 2,333,788; 2,335,259; 2,337,5~2; 2,346,568; 2,366,027;
2,374,193; 2,383,319; 3,312,618; 3,471,403; 3,4g8,284; 3,595,790;
and 3,798,012.
Also included are aliphatic sulfonic acids such as
paraffin wax sulfonic acids, unsaturated paraffin wax sulfonic
acids, hydroxy-substituted paraffin wax sulfonic acids,
hexapropylene sulfonic acids, tetra-amylene sulfonic
'
~3 .
~7~
acids, polyisobutene sulfonic acids wherein the polyiso-
butene contains from 20 to 7000 or more carbon atoms,
chloro-substituted paraffin wax sulfonic acids, nitro-
paraffin wax sulfonic acids, etc.; cycloaliphatic sulfonic
acids such as petroleum naphthene sulfonic acids, cetyl
cyclopentyl sulfonic acids, lauryl cyclohexyl sulfonic
acids, bis-(di-isobutyl) cyclohexyl sulfonic acids, etc.
With respect to the sulfonic acids or salts thereof
described hereln and in the appended claims, it is intended
that the term "petroleum sulfonic acids" or "petroleum
sul~onates" includes all sulfonic acids or the salts thereof
derived from petroleum products. A particularly valuable
group of petroleum sulfonic acids are the mahogany sulfonic
acids (so called because o~ their reddish-brown color)
obtained as a by-product from the manufacture of petroleum
white oils by a sulfuric acid process.
Generally Group I~ and IIB overbased salts of the
above-described synthetic and petro:Leum sulfonic acids are
typically useful in makin~ the film-forming materials (A) of
this invention.
The carboxylic acids from which suitable overbased
salts for use in this invention can be made include ali- ;
phatic, cycloaliphatic, and aromatic mono- and polybasic
carboxylic acids such as the naphthenic acids, alkyl- or
alkenyl-substituted cyclopentanoic acids, alkyl- or alkenyl- `~
substituted cyclohexanoic acids, alkyl- or alkenyl-sub-
stituted aromatic carboxylic acids. The aliphatic acids
generally contain at least eight carbon atoms and preferably
at least twelve carbon atoms. Usually they have no more ~;
than about 400 carbon atoms. Generally, if the aliphatic
-- 10 --
. :
carbon chain is branched, the acids are more oil-soluble for
any given carbon atoms content. The cycloaliphatic and
aliphatic carboxylic acids can be saturated or unsaturated.
Specific examples include 2-ethylhexanoic acid, ~-linolenic
acid, propylene-tetramer-substituted maleic acid, behenic
acid, isostearic acid, pelargonic acid, capric acid, palmi-
toleic acid, linoleic acid, lauric acid, oleic acid, ricin-
oleic acid, undecylic acid, dioctylcyclopentane carboxylic
acid, myristic acid, dilauryldecahydronaphthalene carboxylic
acid, stearyl-octahydroindene carboxylic acid, palmitic
acid, commercially available mixtures of two or more car-
boxylic acids such as tall oil acids, rosein acids, and the
like.
A typical group of oil soluble carboxylic acids ussful
in preparing the salts used in the present invention are the
oil-soluble aromatic carboxylic acids. These acids are
represented by the general formula:
~X
(R*la (Ar*) ~ C-XH) -m Formula IV
wherein R* is an aliphatic hydrocarbon-based group of at
least four carbon atoms, and no more than about 400 ali-
phatic carbon atoms, a is an integer from one to four, Ar*
is a polyvalent aromatic hydrocarbon nucleus of up to about
14 carbon atoms, each X is independently a sulfur or oxygen
atom, and m is an integer of from one to four with the
proviso that R* and a are such that there is an average of
at least 8 aliphatic carbon atoms provided by the R* groups
for each acid molecule represented by Formula IV. Examples
of aromatic nuclei represented by the variable Ar* are the
polyvalent aromatic radicals derived from benzene, naphtha-
7~
lene, anthracene, phenanthrene, indene, fluorene, biphenyl,
and the like. Generally, the radical represented by Ar*
will be a polyvalent nucleus derived from benzene or naphtha-
lene such as phenylenes and naphthylene, e.gO, methylphenyl-
enes, ethoxyphenylenesl nitrophenylenes, isopropylphenylenes,
hydroxyphenylenes, mercaptophenylenes, N,N-diethylamino~
phenvlenes, chlorophenylenes, dipropoxynaphthylenes, tri-
ethylnaphthylenes, and similar tri-, tetra-, pentavalent
nuclei thereof, etc.
The R* groups are usually purely hydrocarbyl groups,
preferably groups such as alkyl or alkenyl radicals. How-
ever, the R* groups can contain small number substituents
such as phenyl, cycloalkyl (e.g., cyclohexyl, cyclopentyl,
etc.) and nonhydrocarbon groups such as nitro, amino, halo
(e.g., chloro, bromo, etc.), lower alkoxy, lower alkyl
mercapto, oxo substituents (i.e., =O), thio groups (i.e.,
=S), interrupting groups such as -NH~, -O-, -S-, and the
like provided the essentially hydrocarbon character of the
R~ group is retained. The hydrocarbon character is retained
for purposes of this invention so long as any non-carbon
atoms present in the R* groups do not account for more than
about 10% of the total weight of the R* groups.
Examples of R* groups include butyl, isobutyl, pentyl,
octyl, nonyl, dodecyl, docosyl, ~etracontyl, 5-chlorohexyl,
4-ethoxypentyl, 4-hexenyl, 3-cyclohexyloctyl, 4-(p-chloro-
phenyl)-octyl, 2,3,5-trimethylheptyl, 4-ethyl-5-methyloctyl,
and substituents derived from polymerized olefins such as
polychloroprenes, polyethylenes, polypropylenes, polyiso-
butylenes, ethylene-propylene copolymers, chlorinated olefin
3G polymers, oxidi~ed ethylene-propylene copolymers, and the
- 12 -
~ ~7~
like. Likewise, the group Ar* may contain non-hydrocarbon
substituents, for example, such diverse substituents as .
lower alkoxy, lower alkyl mercapto, nitro, halo, alkyl or
alkenyl groups of less than four carbon atoms, hydroxy,
mercapto, and the like.
Another group of useful carboxylic acids are those of
the formula: .
/X ~
~ ~ ~ C-X~) m
R* ' Ar*~ Formula V
~ ~f \ (XEI)p
wherein R*, X, Ar*, m and a are as defined in Formula IV and
p is an integer of 1 to 4, usually 1 or 2~ Within this
group, an especially preferred class of oil-soluble car-
boxylic acids are those of the formula:
' O
~ !!
C-OH b
~a ~ Formu1a VI
(OH) c
wherein R** in ~ormula VI is an aliphatic hydrocarbon group
containing at least 4 to about 400 carbon atoms, a is an
integer of from 1 to 3, b is 1 or 2, c is zero, 1, or 2 and
preferably 1 with the proviso that R** and a are such that
the acid molecules contain at least an average of about
twelve aliphatic carbon atoms in the aliphatic hydrocarbon
substituents per acid molecule. And within this latter
group of oil-soluble carboxylic acids, the aliphatic-hydro-
carbon substituted salicylic acids wherein each aliphatic
~ 13 -
7~
hydrocarbon substituent contains an average of at least about
sixteen carbon atoms per substituent and one to -three
substituents per molecule are particularly useful. Salts
prepared from such salicyclic acids wherein the aliphatic
hydrocarbon substituents are derived from polymerized olefins,
particularly polymerized lower l-mono-olefins such as
polyethylene, polypropylene, polyisobutylene, ethylene/
propylene copolymers and the like and having average carbon
contents of about 30 to about 400 carbon atoms.
The carboxylic acids corresponding to Formulae IV-V
above are well known or can be prepared according to procedures
i known in the art. Carboxylic acids of the type illustrated by ;~
~ the above formulae and processes for preparing their overbased -
; metal salts are well known and disclosed, for example, in such
U.S. Patents as ~,197,832; 2,197/835; 2,252,662; 2,252,664;
2,714,092; 3,410,798 and 3,595,791.
Another type of overbased carboxylate salt used in ~ -~
making the film-forming materials (A) of this invention are
those derived from alkenyl succinates of the general formula
R*-fHCOOH Formula VII
2 -
wherein R* is as defined above in Formula IV. Such salts and ~-~
means for making them are set forth in U.S. Patents 3,271,130;
3,567,637 and 3,632,510.
Other patents specifically describing techniques for
making overbased salts of the hereinabove-described sulfonic
acids, carboxylic acids, and mixtures of any two or more of -
- 14 -
. ~,
r
.' ~' , ' "' ' ' ~ ~ ' ' .
these include U.S. Patents 2,501,731; 2,616,904; 2,616,905;
2,616,906; 2,616,911; 2,616,924; 2,616,925; 2,617,049;
2,777,874; 3,027,325; 3,256,186; 3,282,835; 3,384,585;
3,373,108; 3,365,396; 3,342,733; 3,320,162; 3,312,618;
3,318,809; 3,471,403; 3,488,284; 3,595,790 and 3,629,109.
In the context of this invention, phenols are `~ ;
considered organic acids. Thus, overbased salts of phenols ~;
(generally known as phenates) are also useful in making the .
film-forming materials (A) of this invention and well known to
10 those skilled in the art. The phenols from which these phenates ~
are formed are of the general formula ~ ;
(R*)n (Ar*)- - (XH)m Formula VIII
wherein R*, n, Ar*, X and m have the same meaning and preferences
are described hereinabove with reference to Formula IV. The
same examples described with respect to Formula IV also apply.
A commonly available class of phenates are those made
from phenols of ~he general formula
` t~ ~ (OH)b Formula IX ~-
wherein a is an integer of 1-3, b is of 1 or 2, z is 0 or 1,
R' in Formula IX is a substantially saturated hydrocarbon-
based substituent having an average of from 30 to about 400
-~aliphatic carbon atoms and R4 is selected from the gr.oup
- 15 -
. ~
consisting o lower alkyl, lower alkoxyl, nitro, and halo
groups.
One particular class of phenates for use in this
invention are the overbased, Group IIA metal sulfurized phenates
made by sulfuriæing a phenol as described hereinabove with a
sulfurizing agent such as sulfur, a sulfur halide, or sulfide
or hydrosulfide salt. Techniques for making these sulfurized
phenates are described in U.S. Patents 2,680,096; 3,036,971;
and 3,775,321.
Other phenates that are useful are those that are
made from phenols that have been linked through alkylene (e.g.,
methylene) bridges. These are made by reacting single or
multi-ring phenols with aldehydes or ketones, typically, in the
presence of an acid or basic catalyst. Such linked phenates as
well as sulfurized phenates are described in detail in U.S.
Patent 3,350,038; particularly columns 6-8 thereof.
Suitable acids include oil-soluble organic acids such
as phosphorus organic acids, thiophosphorus acids, and the like,
as well as the corresponding alkali and alkaline earth metal
salts thereof. U.S. Patents 2,606,904; 2,695,910; 2,767,164;
2,767,209; 2,777,874; 3,147,232; and 3,274,135 disclose a variety
of overbased products which can be prepared from diverse organic
acid starting materia]s. Overbased acids wherein the acid is a
phosphorus acid, a thiophosphorus acid, phosphorus acid-sulfur
acid combination, or sulfur acid prepared from polyolefins are
disclosed
:~
- 16 -
7~
in U.S. Patents 2,883,340; 2,915,517; 3,001,981; 3,108,960;
and 3,232,883.
Naturally, mixtures of two or more overbased salts of
the hereinabove described organic sulfur acid, phosphorus acid,
carboxylic acids and phenols can be used in the compositions of
this invention. Usually the overbased salts and any neutral
salts used in their preparation will be sodium, lithium,
magnesium, calcium, or barium salts including mixtures of two
or more of any of these overbased or neutral saltsO
A particularly useful type of overbased salt of an
organic acid useful in making the film-forming materials (A)
of the present invention are the "gelled" overbased salts
known to the art as non-Newtonian colloidal disperse systems.
These overbased systems comprise:
(1~ solid, metal-containing colloidal particles pre-
dispersed in at least one diluent and characterized by an
average unit particle size of at least 20 A. and up to about
5,000 A., said particles having been formed in situ in said
non-Newtonian colloidal system from metal containing materials
homogeneously dispersed in a single-phase Newtonian overbased
material, characterized by a metal ratio of at least 1.1;
(~) as an essential third component, at least one
organic compound which is soluble in the dispersing medium ~2),
the molecules of said organic compound being characterized by
a hydrophobic portion and at least one polar substituent.
These non-Newtonian colloidal disperse systems and
their component parts (e.g., diluent, dispersing mediuml
~7~
and organic compounds) are described, for example, in the
following U.S. Patents: 3,492,231; 3,242,079; 3,027,325;
3,488,284; 3,372,114; 3,411,923; 3,372,115; 3,422,013;
3,350,308; 3,312,618; 3,376,222; 3,471,403; 3,453,124; 3,377,283;
3,595,790; 3,766,067; 3,766,066; 3,671,012; and 3,384,586.
In these non-Newtonian systems at least a portion of
the particles dispersed therein are solid metal-containing
particles formed in situ. The size of these particles is not
critical as long as they are dispersed in the form, for example,
of colloids or colloidal solutions. Ordinarily, the particles
do not exceed 5000 angstroms in size. Generally, the maximum
unit particle size is less than about 1000 angstroms, usually
less than 400 angstroms. Disperse systems having unit particle
size in the range of 30 angstroms to 200 angstroms has been
found to give excellent results. The term "unit particle size"
is defined in the above-noted '586 patent.
The solid metal-containing particles are metal salts
of inorganic acids and low molecular weight organic acids (such
as carbonic, acetic and propionic acids), hydrates thereof, or
mixtures Gf two or more of these. These salts are usually
alkali and alkaline earth formates, acetates, carbonates,
hydrogen carbonates, hydrogen sulfides, sul
- 18 -
~7~
~ides, sulfates, hydrogen sulfates and halides. Magnesium,
calcium and barium salts are typical examples. Typically then
the metal particles are solid metal-containing colloidal
particles consisting essentially of alkaline earth metal salts,
these salts being ~urther characterized by having been formed
in situ.
Colloidal disperse systems used in the agents of this
invention also comprise at least about one liquid dispersing
medium. The identity of the medium is not a critical aspect
of the invention as the medium serves primarily as a liquid
vehicle in which the solid particles are dispersed. Normally
it consists of one or more substantially inert, nonpolar
oleaginous liquids. These liquids are thus substantially
chemically inactive in the particular environment in question.
In other words, they do not interact chemically with the other
components of their environment in such a way as to substantially
alter their chemical nature. The liquid dispersing medium may
be substantially volatile or non-volatile at standard temperature
and pressure. Of-ten the non-Newtonian disperse system is
prepared in such a manner that a mixture of such volatile and
nonvolatile organic liquids is used as the dispersing medium
thus permitting easy removal of all or a portion of the volatile
component by heating. This is an optional and often desirable
means for controlling the viscosity or fluidity of the disperse
system.
Typical dispersing media are disclosed in U.S. Patent
3,384,586. These media include liquids such as mineral oils
and synthetic oils as well as other organic
- 19 -
r 7 ~g~
liquids such as ethers, alkanols, alkylene glycols, ketones,
and the like.
From the standpoint of availabili-ty, cost and
performance, liquid hydrocarbons and particularly liquid
petroleum fractions represent particularly useful dispersing
media. Included within these classes are alkylated benzenes,
and napthene-based petroleum fractions, paraffin-based
petroleum fractions, petroleum ether, petroleum napthas, mineral
oil, Stoddard Solvent, and mixtures thereof. Typically, the
dispersing medium is mineral oil or at least about 25~ of the
total medium is mineral oil. Often at least about 50% of the
dispersing medium is mineral oil. As noted, mineral oil can
serve as the exclusive dispersing medium or it can be combined
with some non-mineral oil organic liquid such as, for example,
the fluidizers described infra.
Preferably, (E) the overbased non-Newtonian system is
derived from one or more alkali metal, alkaline earth metal or
alkali/alkaline earth mixed metal overbased salts of at least
one organic sulfonic acid, carboxylic acid or mixtures of same.
Especially preferred are non-Newtonian overbased calcium
sulfonates of alkyl benzene sulfonic acid such as disclosed in
U.S. Patent 3,492,231.
The clays (B-2) useful in the compositions of the
present invention are those which are capable of thickening
aqueous slurries containing them. Many such clays are known
to those of skill in the art. See, for example, "Applied
Clay Minerology" by Ralph E. Grim, McGraw & ~Iill Book Co.,
- 20 -
7~
New York (1962); as well as U.S. Patents 3,095,339; 2,652,341;
and 1,398,201. Typically, montmorillonite-type clays are
useful. Among the montmorillonite-type clays that have found
use in the compositions of this invention are bentonite,
hectorite and mixtures thereof.
An important component of the compositions of the
present invention is a clay flocculating agent, (C), which
interacts with the clay in such a fashion as to promote its
ability to thicken aqueous slurry. These flocculating agents
also act as film stabilizers to stabilize the films formed by
removal of water from the disperse composition. Such
flocculating agents are generally polyvalent metal salts of
metals such as copper, aluminum and the like and are derived
from sulfuric, chromic, formic, acetic acid and mixtures of
such acids. A suitable description of useful flocculating
agents is found on page 396 of McBain's "Colloid Science"
published by Heath in 1950. Copper salts are particularly
useful flocculating agents and a typical useful copper salt is
cupric sulfate. Usually the use of a montmorillonite-type clay
as described above in conjunction with a clay flocculating agent
results in an aqueous disperse composition which is thixotropic.
As known to those in the art, this thixotropic property is
desirable when the compositions are used in certain coating
application.
The compositions of the present invention can also
include one or more supplemental additives or adjuvants. Such
supplemental additives inhibit corrosion of metal and provide
freeze/thaw stability under conditions of changing temperatures,
etc. Buffers which aid in maintaining the pH
- 21 -
B
~Lq3 a~7~
of the whole aqueous disperse composition, and particularly
the slurry which serves as its external phase, are in the
desired range of about 6 to about 9.
The compositions of this invention can include one or
more viscosity modifying agents. It is contemplated that a
composition may contain a viscosity increasing or viscosity
reducing agent. Each may be added at different stages in
the production of the composition. For example, it may ~e
desirable to reduce the composition's viscosity while it is
being made and then thicken it after it has been formulated.
Such techniques are known to those skilled in the art.
Among the useful viscosity reducing agents (also known as
fluidizers) are the dispersing media described supra, such
as inert liquid organic solvent/diluents. Viscosity in-
creasing composition that can be used include fillers such
as talc, silica, calcium carbonate and the like for purposes
well known to those of skill in the art. Naturally, mi~tures
of various viscosity modifying agents can be used.
A generally desirable supplemental additive for the
compositions of this invention (when they are to be used in
coating ferrous material) is a flash antirust agent. Such
agent prevents rusting of metal surfaces immediately upon
coating with the aqueous disperse composition. While the
films formed by water removal from the aqueous disperse
compositions of the present invention serve to prevent
corrosion of such surfaces once they are formed, flash
antirust agents are used in preventing rusting before the
films have had a chance to form. A typical flash antirust
agent is a phosphoric acid ester neutralized with tetra-
ethylene pentamine. Such materials are well known to those
of skill in the art.
- 22 -
~97~
Typical buffers used in the compositions of this
invention include potassium dichromate/acetic acid and
potassium dichromate/phosphoric acid combinations. Acetic
acid can also serve as a viscosity thinning agent. The
combination of phosphoric acid-based flash antirust agent
and dichromate/acetic acid buffer or dichromate/phosphoric
acid systems has also been found to give desirable freeze/
thaw stability to the aqueous disperse compositions of this
invention.
The aqueous disperse compositions of the present
invention generally contain about 5 to about 50, typically
about 10 to about 40, weight percent of the total disperse
composition of (A), the afore-described film-forming material;
about 1 to about 10, typically about 2 to about 6, weight
percent of the disperse composition of (B-2), the afore-
described clay on a non-hydrated basis The flocculating
agent (C) is present in an amount of about l to about 40,
typically about 2 to about 25, percent by weight of the
amount of clay (B-2) present. The supplemental additives or
adjuvants when used are used in their normal conventional
concentrations such as, for e~ample, about l to about 15
percent supplemental corrosion inhibitor, about 1 to about
10 percent flash antirust agent/ about 0.01 to about l
percent buffer system and about Ool to about 10 percent
viscosity modifier. Since the COmpQsitiOn is aqueous it
contains water; usually it contains at least about 10 per-
cent water, often about 25 percent water. All the per-
centages just recited are ~eight percents of the total
disperse composition.
Generally the aqueous disperse composition of the
- 23 -
~7~
present invention are made by combining the oleaginous film-
forming material (A) and the clay slurry (B-l) containing
the clay (B-2) and the flocculating agent (C). In these
aqueous disperse compositions (A) comprises the internal
phase and the clay slurry (B-l) the external phase. Care is
taken to adjust the pH of the composition within the desired
range.
A typical disperse aqueous composition can be made by
the method which comprises the steps of:
(I) hydrating a thic~ening amount of at least one clay
(B-2) to form an aqueous clay slurry (B-l);
(II) optionally, treating the aqueous clay slurry (B-l)
with any desired supplemental additives selected from the
group consisting of inhibitors of corrosion of metal, bu~fers,
freeze/thaw stabilizers and viscosity modifying agents to
form an augmented aqueous clay slurry (B-3);
(III~ treating the aqueous clay slurry (B-l) or aug-
mented aqueous clay slurry (B-3) with at least one floccu-
lating agent (C) to form a txeated aqueous clay slurxy or
treated augmented aqueous clay slurry;
(IV~ reacting at least one carboxylic acid (~) with at
least one overbased salt of an organic acid (E) which is
typically an overbased, non-Newtonian colloidal system
comprising
(a) solid, metal-containing colloidal particles
predispersed in at least one liquid dis-
persing medium (2) and characterized by an
- 24 -
~ 74~
average unit particle size of at least 20 A.
and up to about 5000 A., said particles
having formed in situ in said disperse
. composition from metal-containing materials
homogeneously dispersed in a single phase
Newtonian overbased material characterized by
a metal ratio of at least 1.1;
(b) as an essential third component, at least one
organic compound which is soluble in said
dispersing medium t2), the molecules of said :~
organic compound being characterized ~y a
hydrophobic portion and at least one polar
substituent to form a film-forming oleaginous
material (A),
(V) optionally fluidizing, as desired, the oleaginous
material (A) to form a fluidized material (F);
(VI) optionally adding at least one resin to the
aqueous clay slurry (B-l) and/or the fllm-forming oleaginous
material (A~ or fluidized material (F); ana
(VII) combining the ~ilm-forming oleaginous material (A)
or fluidized material (F) with the aqueous clay slurry (B-l)
to form a dispersed composition having the oleaginous
material (A) or fluidized material (F) comprising the inter-
nal phase and the aqueous clay slurry (B-l) comprising the
external phase.
Usually the hydrating and treatment steps are carried
out at temperatures in the range of about 15 to about
85C.; typically, temperatures of about 70 to about 80C.
are used. The reaction of the carboxylic acid (D) with the
overbased non-Newtonian colloidal system (E) is usually
- 25 -
carried out at temperatures ranging from about 20 to about
120C. The optional fluidizing step, if it is desired to
further reduce the composition's viscosity below that
exhibited by the material (A) itself, is carried out at
temperatures which fluidize the oleaginous film-forming
material and usually fall in the range of about 20 to about
150C. The optional step of adding at least one resin is
carried out within the same temperature range. The com-
bination of the oleaginous film-forming material (A~ with
the aqueous clay slurry (B-l) is generally carried out at a ~ ;
temperature range of about 15 to about 75C. Mixing by ~ !
agitation or stirring usually accompanies each of the steps
in the method. ~ -
Generally each of the above steps can be carried out at
about 0.15 to about 24 hours indiviclually. In certain
instances, the hydration step (I) and the combining step
(VII) are conveniently carried out for periods of about 2 to
about 18 hours each.
As noted above, the method for preparing the aqueous
disperse compositions of this invention can optionally
include the step of adding at least one resin to the aqueous
clay slurry and/or the oleaginous film-forming materials.
Among the useful resins are commercially available polymers
such as polyethylene, ethylene/propylene copolymer, vinyl
acetate, polyvinyl chloride, polybutadiene and the like.
Hydrocarbon resins, typically synthetic waxes, are parti-
cularly useful in making rust-proofing coatings. Micro-
crystalline waxes can also be used.
The resin, whatever its specific nature, func~ions to
aid in the formation of coherent films and~or in providing
- 26 -
the film coating produced from the compositions of this
invention by removal of water with desired properties such as
adhesiv~ness, corrosion inhibition, heat stability and the
like.
It is a feature of this invention that the disperse
compositions are capable of irreversibly forming coherent films.
This means that as water is removed from the composition
(through, for example, drying of a coating) a coherent film is
irreversibly formed. Once the film has formed by removal of a
substantial portion of water, it is not possible to reverse i-ts
formation by the addition of water to raform the original
disperse composition.
The aqueous disperse compositions of this invention
are useful in forming corrosion resistant and inhibiting coatings
or films for metal surfaces such as surfaces of ferrous metals,
galvanized metal, aluminum, or magnesium, where their
irreversible capability is of significant utility. They are
especially useful for internally rust proofing and undercoating
automotive bodies and the like. They may be employed in these
applications alone or in combinations with other known corrosion
resistant materials such as aforedescribed supplemental
additives and adjuvants. Other known adjuvants for such
corrosion inhibiting coatings such as the resins discussed above
and many types of petroleum and synthetic waxes may also be
used with them. These materials can be incorporated in varying
amounts in the aqueous disperse compositions but generally they
comprise minor amounts of the composition; typically, about 0.5
to about 5 percent by weight. U.S. Patents 3,453,124 and 3,671,072
disclose
~7~
basic compositions and adjuvants which are useful in com-
bination with the aqueous disperse composition of the pre-
sent invention.
When used ~or corrosion inhibiting purposes, the
aqueous disperse compositions of this invention are gen-
erally applied to the surface to be protected and then a
substantial amount of the water present in the composition
removed through evaporation either in ambient or elevated
temperature to form an irreversibly coherent film, generally
a substantial amount of water is removed to form the film.
Usually, this is in the range of about 80 to about 99 per-
cent of the water originally present These films, as well
as articles of manufacture ~ully or partially coated with
such films are also ~ithin the scope of the present inven- ~;
tion.
When used for corrosion inhibiting purposes, the
aqueous disperse compositions of the present invention may
be applied to the metal surface by any ordinary method such
as brushing, spraying, dip-coating, flow-coating, roller
coating and the like. The viscosity of the aqueous disperse
composition may be adjusted for the particular method of
application selected by adding, if necessary, a substan-
tially inert, normally liquid organic diluent or other
viscosity modifying agent as discussed hereinabove. Mech-
2~ anical shearing techniques can also be used to vary the
viscosity of these aqueous compositions since they are
thixotropic in nature. This shearing can be accomplished by
using agitators or by forcing the composition through pumps
(e.g., gear pumps) or devices such as nozzles. Also, the
amount of water present in the aqueous disperse composition
- 28 -
7~
may be adjusted to give the desired viscosity. The coated
metal surfaces can then be dried hy exposure to ambient air
or by baking. The film thickness produced is not critical,
although coatings of about 50 to about 2,000 milligrams per
square foot of coated surface is generally sufficient to
provide adequate corrosion protection. Heavier coatings can
be used if desired, particularly if the metal article is to
be subjected to severe corrosion enhancing conditions,
abrasion and/or to be stored for long periods of time.
The following non-limiting examples illustrate the
practice of the invention and include the presently known
best mode of practicing the invention All temperatures are
in degrees Celcius and all percentages and parts are by
weight unless it is specifically noted to the contrary (as
they are throughout the rest of the specification and
appended claims).
Example 1
A hydrated clay slurry is prepared by the incremental
addition of 240 parts of Bentonite 200, a commercially
available clay from Barroid Division of N. L. Industries, to
3,750 parts of water at ambient temperatures while mixing
B with a Cowles type mixer. The mixing is continued until the
slurry is smooth and no agglomerations are noticeable. The
slurry is filtered through a 60-mesh screen and the clay is
allowed to further hydrate overnight.
Exampl-e 2
The procedure of Example 1 is repeated using 651 parts
of Bentonite 200 clay and 7,550 paxts of water.
Example 3
A film-forming material is prepared by slow addition at
- 29 -
~L~97~
77C. of 144 parts of a 50/50 by weight mixture of isopropyl
alcohol and water to a mixture of 821 parts of a ~olypro-
penyl (Mn=1,000) substituted succinic anhydride and 2,860
parts of an overbased, non-Newtonian colloidal disperse
system made by gelling in the presence of a water/alcohol
mixture an overbased, carbona~ed calcium petroleum sulfonate
wherein the free sulfonic acid has an approximate molecular
weight of 430. The overbased sulfonate has a metal ratio of
12 and a mineral oil content of 50%. The overbased calcium
petroleum sulfonate itself is made according to the pro-
cedure described in U.S. Patent 3,350,308. The gelling
procedure is that described in U.S. Patent 3,492,231~ The
reaction mixture is heated at 77C. :Eor 2.5 hours under
nitrogen and then stripped at 150C. under nitrogen. The
residue is the desired film forming material.
Example 4
An oleaginous film-forming material is prepared by slow
addition, at 77C., of 452 parts of water and 230 parts
isopropyl alcohol, to a mixture of 5,000 par~s of the
overbased, non-Newtonian colloidal disperse system descri~ed -~
in Example 3 and 2,145 parts of an oxidized petrolatum
fraction available from Ashland Oil Company and known as
D Tectyl 3050. This oxidized petrolatum has an acid numher of
57 measured by ASTM D-664. The reaction mixture is heated
to 77C. for 2.5 hours under nitrogen and then stripped at
150C. under nitrogen. The residue is the film-forming
material.
Example 5
A film-forming material is prepared by the careful and
slow addition of 144 parts of a 50~50 by weight mixture of
....
~ C? ~
- 30 -
~7~
isopropyl alcohol and water to a mixture of 2,176 parts of
the overbased, non-Newtonian colloidal disperse system
described in Example 3, 700 parts of the oxidized petrolatum
fraction described in Example 4, and 233 parts of a poly-
propenyl (Mn=l,000) substituted succinic anhydride at 77C.
The reaction mixture is heated at 77C. for 2.5 hours under
nitrogen and then stripped at 150C. under nitrogen. The
residue is the desired product.
A treated clay slurry is prepared by the addition of
30.4 parts of a buffer solution made up of 8% potassium
dichromate, 8% glacial acetic acid and 84% water; an addi
tional 9,6 parts o~ glacial acetic acid; and 67.2 parts of a
6.4% aqueous cupric sulfate solution to 10,368 parts of a
hydrated clay slurry prepared as described in Example 1 at
60C.
Example 7
A treated clay slurry is prepared ~y the addition of 20
parts of a buffer solution made up of 8% potassium dichro-
matel 8~ glacial acetic acid and 84% water; an additional 6
parts of glacial acetic; and 45 parts of a 6.4% aqueous
cupric sulfate solution to 5,192 parts of a hydrated clay
slurry prepared as described in Example 2 at 60C.
Example 8
To 10,475 parts of the treated clay slurry prepared as
described in Example 6, is slowly added 4,803 parts of a
film-forming material prepared as described in Example 3
which has been preheated to 99~C. The mixture is stirred
for 0,5 hour to assure homogenity of the emulsion, At room
temperature, an addition of 250 parts of water is made to
- 31 -
~7~
replenish evaporation losses. A rust inhibitor (394 parts),
the neutralization product of one part of a phosphate ester
of an ethoxylated linear alcohol commercially available from
G. Ao F. Corporation as A~TARA LK-500 and 2 parts of tri-
ethanolamine, is then added to the emulsion. Aqua-100 (78
parts), a black pigment dispersion from Borden Chemical is
then added to the emulsion. After mixing for 5 minutes; a
; filler (40 parts), Cab-O-Sil', a microscopic fire-dry, fumed
silica, available from Cabot Corporation is added, followed
by slow mixing to deaerate the emulsion.
Example 9
To 5,263 parts of the treated clay slurry prepared as
described in Example 7 is slowly added 3,210 parts of film-
forming material prepared as described in Example 3 which ;~
has been preheated to 99C. The mixture is stirred for 0.5
hours to assure homogenity of the emulsion. At room tempera-
ture, an addition of 113 parts of water is made to replenish
evaporation losses. ~ rust inhibitor (320 parts~ as des-
cribed in Example 8 is then added to the emulsion. Aqua-100
(50 parts), a black pigment dispersion from ~orden Chemical
i5 then added to the emulsion. After mixing for 5 minutes;
a filler (30 parts), Cab-O-Sil is added, followed by slow
mixing to deaerate the emulsion.
Exam~e 10
To 6,540 parts of the treated clay slurry prepared as
described in Example 6 is slowly added 2,260 parts of a
film-forming material prepared as described in Example 4 ;?
which has been fluidized by reheating to 99C. The mixture
is stirred for 0.5 hour to assure homogenity of the emulsion. i
At room temperature, 270 parts of the rust inhibitor described
- 32 -
in Example 8 and 890 parts of a proprietary rust inhibitor
composition are added to the emulsion. Aqua-100 (40 parts),
a black pigment dispersion ~rom Borden Chemical is then
added to the emulsion. After thorough mixing, the emulsion
is deaerated by slow mixing.
Example 11
To 6,500 parts of the treated clay slurry prepared as ~,
described in Example 6 is slowly added 2,320 parts of a
film-forming material prepared as described in Example 5
which has been fluidized by reheating to 99C. The mixture
is stirred for 0.5 hour to assure homogenity of the emul-
sion. At room temperature, 270 parts of the rust inhibitor
described in Example 8 and 900 parts of a proprietary rust
inhibitor composition are then added to the emulsion. After
thorough mixing, the emulsion is deaerated by slow mixing.
Example 12
A clay slurry is prepared from 12.63 parts of the
bentonite clay described in Example 1 and 145.28 parts of
water in essentially the same manner as described in Example
1.
Example 13
The ingredients outlined in the following table are
assembled:
TABLE
Parts by
Ingredi-ents Description W
1 Clay Slurry Example 12 57.44
2 8% Aqueous K2Cr2O7 ~ 0,23
3 10% Aqueous H3PO4 ----- 0.32
4 10% Aqueous ~ 0,5Q
CuS04 ' 5~2O
Film Forming E~ample 3 35.4S
Material
6 Stoddard Solvent ----- 5.50
7 Water ----- 6.75
8 Black Pigment ----- 0.58
9 Rust Inhib~ tor Example 8 2.9
10 Cab-O-Sil Example 8 0.3
~r ~e ,~ ~ - 33
.
,-. : . ~- . .
~ 7~
The hydrated clay slurry is heated to about 65 over a 30~
minute period while mixed with a propeller-type steel mixer
and water is added to compensate for evaporation losses.
Ingredients 2, 3 and 4 are added sequentially. The film-
forming material is preheated to 100 and slowly added to
the slurry so as to avoid splashing. The slurry is cooled
to about 60 and items 6 and 7 are added slowly. The
addition of ingredient 6 causes a significant increase in
viscosity. Items 8, 9 and lO are then slowly added sequen-
tially while the mixture is agitated at a temperature of
about 38. The resultant product was a highly thixotropic -
soft gel-like black material having a solids content of 39~
as determined by evaporation of a sample for three hours at
110.
- 34 -
