U.S. patent application number 11/389607 was filed with the patent office on 2007-09-27 for enhanced antistatic additives for hydrocarbon fuels & solvents.
Invention is credited to Cyrus Pershing JR. Henry.
Application Number | 20070220803 11/389607 |
Document ID | / |
Family ID | 38531850 |
Filed Date | 2007-09-27 |
United States Patent
Application |
20070220803 |
Kind Code |
A1 |
Henry; Cyrus Pershing JR. |
September 27, 2007 |
Enhanced antistatic additives for hydrocarbon fuels &
solvents
Abstract
Described herein are enhanced performance of antistatic additive
compositions for hydrocarbon fuels, the compositions comprising
olefin-sulfur dioxide copolymers in combination with polymeric
polyamines prepared using an ortho-xylene solvent.
Inventors: |
Henry; Cyrus Pershing JR.;
(Avondale, PA) |
Correspondence
Address: |
BURNS & LEVINSON, LLP
125 SUMMER STREET
BOSTON
MA
02110
US
|
Family ID: |
38531850 |
Appl. No.: |
11/389607 |
Filed: |
March 24, 2006 |
Current U.S.
Class: |
44/370 ;
44/432 |
Current CPC
Class: |
C10L 1/143 20130101;
C08K 5/42 20130101; C08L 79/02 20130101; C10L 1/2225 20130101; C10L
1/238 20130101; C10L 1/2383 20130101; C08L 79/02 20130101; C10L
1/221 20130101; C10L 1/2222 20130101; C08L 81/06 20130101; C10L
1/2437 20130101; C10L 1/2468 20130101; C10L 1/1608 20130101; C10L
1/146 20130101; C10L 1/2462 20130101; C10L 1/2475 20130101; C10L
1/2641 20130101; C08L 81/00 20130101 |
Class at
Publication: |
044/370 ;
044/432 |
International
Class: |
C10L 1/24 20060101
C10L001/24; C10L 1/22 20060101 C10L001/22 |
Claims
1. An antistatic additive composition for hydrocarbon fuels
comprising, based on total weight, i. from about 1 to 50 percent of
polysulfone, ii. from about 1 to 50 percent of polymeric polyamine,
iii. from about 1 to 30 percent of oil-soluble sulfonic acid, and
iv. from about 3 to 97 percent of solvent, said polysulfone of (i)
comprising about 50 mol percent of units from sulfur dioxide, about
40 to 50 mol percent of units derived from one or more 1-alkenes
each having from about 4 to 24 carbon atoms, and from about 0 to 10
mol percent of units derived from an olefinic compound having the
formula ACH.dbd.CHB wherein A is a group having the formula
--C.sub.xH.sub.2x)--COOH wherein x is from about 0 to about 17, and
B is hydrogen or carboxyl, with the proviso that when B is
carboxyl, x is 0, and wherein A and B together can be a
dicarboxylic anhydride group, said polymeric polyamine of (ii)
having the formula ##STR14## wherein R.sup.1 is an aliphatic
hydrocarbyl group of 8 to 24 carbon atoms, R.sup.2 is an alkylene
group of 2 to 6 carbon atoms, R is R.sup.1, or, an N-aliphatic
hydrocarbyl alkylene group of the formula R.sup.1NHR.sup.2, a is an
integer of 0 to 20, b is an integer of 0 to 20, c is an integer of
0 to 20, and x is an integer of 1 to 2, with the proviso that when
R is R.sup.1 then a is an integer of 2 to 20 and b=c=0, and when R
is R.sup.1NH--R.sup.2 then a is 0 and b+c is an integer of 2 to 20,
said oil-soluble sulfonic acid of (iii) being
dodecylbenzenesulfonic acid, and said solvent of (iv) being
ortho-xylene.
2. The composition of claim 1, wherein said polysulfone has an
molecular weight ranging from about 10,000, to about 1,500,000
amu.
3. The composition of claim 1, wherein said polysulfone is selected
from the group consisting of 1-hexene, 1-heptene, 1-octene,
1-nonene, 1-decene, 1-undecene, 1-dodecene, 1-tridecene,
1-tetradecene, 1-pentadecene, 1-hexadecene, 1-heptadecene,
1-octadecene, 1-nonodecene, 1-eicosene, 1-heneicosene, 1-docosene,
1-tricosene, and 1-tetracosene.
4. The composition of claim 3, wherein said polysulfone is
1-decene.
5. The composition of claim 1, wherein said polymeric polyamine is
a polymeric reaction product of epichlorohydrin with an aliphatic
primary monoamine or N-aliphatic hydrocarbyl alkylene diamine.
6. The composition of claim 5, wherein said aliphatic primary
monoamine is selected from the group consisting of octylamine,
nonylamine, decylamine, undecylamine, dodecylamine,
tridedecylamine, tetadecylamine, pentadecylamine, hexadecylamine,
heptadecylamine, octdadecylamine, nonadecylamine, eicosylamine,
heneicosylamine, docosylamine, tricosylamine, and
tetracosylamine.
7. The composition of claim 5, wherein said N-aliphatic hydrocarbyl
alkylene diamine is selected from the group consisting of N-octyl,
N-nonyl, N-decyl, N-undecyl, N-dodecyl, N-tridecyl, N-tetradecyl,
N-pentadecyl, N-hexadecyl, N-heptadecyl, N-octadecyl, N-nonadecyl,
N-eicosyl, N-uneicosyl, N-docosyl, N-tricosyl, N-tetracosyl, as
well as the corresponding N-alkenyl derivatives of ethylenediamine,
propylenediamine, butylenediamine, pentylenediamine, and
hexylenediamine
8. The composition of claim 1, wherein a weight ration of said
polysulfone to said polyamine ranges from about 100:1 to about
1:100.
9. The composition of claim 1, wherein a weight ration of said
polysulfone to said polyamine ranges from about 50:1 to about
1:1.
10. The composition of claim 1, wherein a weight ration of said
polysulfone to said polyamine ranges from about 20:1 to about
1:1.
11. The composition of claim 1, wherein said sulfonic acid is
either a mono or di sulfonate of alkyl benzene.
12. The composition of claim 11, wherein said sulfonic acid is
either dodecylbenzene sulfonic acid or dinonylnaphthyl sulfonic
acid.
13. A hydrocarbon fuel boiling range of from about 200 to about
375.degree. C. having from about 0.01 ppm to about 40 ppm of said
composition defined in claim 1.
14. An antistatic additive composition comprising, based on total
weight, i. from about 1 to 50 percent of polysulfone, ii. from
about 1 to 50 percent of polymeric polyamine, and iii. from about 3
to 97 percent of solvent, said polysulfone of (i) comprising about
50 mole percent of units from sulfur dioxide, about 40 to 50
percent of units derived from one or more 1-alkenes each having
from about 4 to 24 carbon atoms, and from about 0 to 10 mol percent
of units derived from an olefinic compound having the formula
ACH.dbd.CHB wherein A is a group having the formula
--C.sub.xH.sub.2x)--COOH wherein x is from 0 to about 17, and B is
hydrogen or carboxyl, with the proviso that when B is carboxyl, x
is 0, and wherein A and B together can be a dicarboxylic anhydride
group, said polymeric polyamine of (ii) having the formula
##STR15## wherein R.sup.1 is an aliphatic hydrocarbyl group of 8 to
24 carbon atoms, R.sup.2 is an alkylene group of 2 to 6 carbon
atoms, R is R.sup.1, or, an N-aliphatic hydrocarbyl alkylene group
of the formula R.sup.1NHR.sup.2, a is an integer of 0 to 20, b is
an integer of 0 to 20, c is an integer of 0 to 20, and x is an
integer of 1 to 2, with the proviso that when R is R.sup.1 then a
is an integer of 2 to 20 and b=c=0, when R is R.sup.1NH--R.sup.2
then a is 0 and b+c is an integer of 2 to 20, and said solvent of
(iii) being ortho-xylene.
15. An antistatic additive composition comprising, based o total
weight, i. from about 1 to 50 percent of polysulfone, ii. from
about 1 to 50 percent of polyamine, iii. from about 0.5 to 5
percent of quaternary ammonium compound, iv. from about 1 to 30
percent of oil-soluble sulfonic acid, and v. from about 3 to 97
percent of solvent, said polysulfone of (i) comprising about 50 mol
percent of units derived from sulfur dioxide, from about 40 to 50
mol percent of units derived form 1-alkene of 4 to 24 carbon atoms
and 0 to about 10 mol percent of units derived from an olefin
having the formula, ACH.dbd.CHB, wherein A is a group having the
formula --(C.sub.xH.sub.2x)--COOH wherein x is from 0 to about 17,
and B is hydrogen or carboxyl, with the proviso that when B is
carboxyl, x is 0, and wherein A and B together can be a
dicarboxylic anhydride group, said polyamine of (ii) having the
formula ##STR16## wherein R.sup.1 is an aliphatic hydrocarbyl group
of 8 to 24 carbon atoms, R.sup.2 is an alkylene group of 2 to 6
carbon atoms, R is R.sup.1, or, an N-aliphatic hydrocarbyl alkylene
group of the formula R.sup.1NHR.sup.2, a is an integer of 0 to 20,
b is an integer of 0 to 20, c is an integer of 0 to 20, and x is an
integer of 1 to 2, with the proviso that when R is R.sup.1 then a
is an integer of 2 to 20 and b=c=0, and when R is
R.sup.1NH--R.sup.2 then a is 0 and b+c is an integer of 2 to 20,
the quaternary ammonium compound of (iii) having the formula
##STR17## wherein Alk.sup.1 and Alk.sup.2 are the same or different
alkyl groups having from 1 to 22 carbon atoms, Alk.sup.3 is
selected from the group consisting of alkyl groups of 1 to 22
carbon atoms and ##STR18## where Alk.sup.3 is hydrogen or methyl
and n is 1 to 20, Alk.sup.4 is selected from the group consisting
of (a) an alkyl group having 1 to 22 carbon atoms, (b) an aralkyl
group having from 7 to 22 carbon atoms, (c) a ##STR19## group as
defined above, (d) a ##STR20## group, wherein Alk.sup.6 and
Alk.sup.7 are the same or different alkyl groups having from 11 to
19 carbon atoms, and (e) an --Alk.sup.8--CO.sub.2 group wherein
Alk.sup.8 is a hydrocarbyl group having from 1 to 17 carbon atoms,
with the proviso that when Alk.sup.1, Alk.sup.2, Alk.sup.3 and
Alk.sup.4 are each alkyl groups, at least one of them is an alkyl
group having at least 8 carbon atoms, A is an anion, z is 0 or 1, z
is 0 when Alk.sup.4 is (d) or (e), and y is at least 1, y is equal
to the ionic valence of anion A when z is 1, said composition
comprises, in combination therewith, said oil-soluble sulfonic acid
of (iv) being dodecylbenzenesulfonic acid, and said solvent of (v)
being ortho-xylene.
16. The composition of claim 15, wherein said quaternary ammonium
is dicocodimethyl ammonium nitrite.
17. A composition comprising a major proportion of a suitable fuel
oil and a minor portion of a suitable additive.
18. The composition of claim 17, wherein said suitable fuel oil is
selected from the group consisting of a petroleum-based fuel,
kerosene, jet fuel oil, middle distillate heating oils, and diesel
fuel oil.
19. The composition of claim 18, wherein said petroleum-based fuel
is a gasoline or middle distillate fuel oil.
20. The composition of claim 17, wherein said suitable additive is
an additive defined by claim 1.
Description
FIELD OF THE INVENTION
[0001] This invention concerns an improved two-component antistatic
additive for hydrocarbon fuels and solvents to render them
electrically conductive. One component is an olefin-sulfur dioxide
copolymer (polysulfone copolymer) prepared in orthoxylene, and the
other component is a particular polymeric polyamine.
BACKGROUND OF THE INVENTION
[0002] Hydrocarbon fuels normally are very poor conductors of
electricity. Electrical charges, therefore, tend to accumulate in
the fuel and can be discharged as sparks thus creating the danger
of an explosion or fire should such charges ignite hydrocarbon-air
admixtures that may be present.
[0003] Numerous materials have been suggested in the art to
increase the electrical conductivity of hydrocarbon fuels.
Suggested materials include two-component additives where one
component is a polysulfone and the other is a quaternary ammonium
compound. Another suggested two-component additive comprises
polysulfone as one component and polyvalent metal organic compounds
of metals having an atomic number of from 22 to 29 as the other
component.
[0004] An important aspect is the solvent used for the
polymerization of the poly Sulfone component. Typically, solvents
such as benzene, toluene, et al. have been employed. These solvents
contain impurities which may result in a potentially toxic
situation. Thus, there is a clear need to employ a safer
solvent.
BRIEF SUMMARY OF THE INVENTION
[0005] The two-component antistatic additives of this invention are
characterized by being highly effective at low levels of usage and
by being ashless upon burning. These two-component antistatic
additives are so efficient that even at relatively low
concentrations they provide the desired conductivity (measured in
picomhos per meter, or picoSiemens/meter) in nearly all
hydro-carbon fuels. This performance is enhanced when the solvent
for polymerization of the olefin and sulfur dioxide is
ortho-xylene.
[0006] In the antistatic additive of this invention wherein the
components are presented in a weight ratio of 100:1 to 1:100, and
wherein one component is a polysulfone copolymer prepared in
ortho-xylene solvent comprising about 50 mol percent of units from
sulfur dioxide, about 40 to 50 mol percent of units derived from
one or more 1-alkenes each having from about 4 to 24 carbon atoms,
and from about 0 to 10 mol percent of units derived from an
olefinic compound having the formula ACH.dbd.CHB wherein A is a
group having the formula --(C.sub.xH.sub.2x)--COOH wherein x is
from 1 to about 23, and B is hydrogen or carboxyl, with the proviso
that when B is carboxyl, x is 1, and wherein A and B together can
be a dicarboxylic anhydride group, the antistatic composition
comprises, in combination with said polysulfone component, a
polymeric polyamide of the formula ##STR1##
[0007] R.sup.1 is an aliphatic hydrocarbyl group of 4 to 24 carbon
atoms,
[0008] R.sup.2 is an alkylene group of 2 to 6 carbon atoms,
[0009] R is R.sup.1, or, an N-aliphatic hydrocarbyl alkylene group
of the formula R.sup.1NHR.sup.2, [0010] a is an integer of 0 to 20,
[0011] b is an integer of 0 to 20, [0012] c is an integer of 0 to
20, and [0013] x is an integer of 1 to 2,
[0014] with the proviso that when R is R.sup.1 then a is an integer
of 2 to 20 and b=c=0, and when R is R.sup.1 NH--R.sup.2 then a is 0
and b+c is an integer of 2 to 20.
[0015] Particular embodiments of this invention are those wherein
the polysulfone is composed solely of units derived from sulfur
dioxide and units derived from at least one 1-alkene of from 4 to
24 carbon atoms. A particular embodiment is that wherein the
1-alkene is 1-decene and is prepared in an ortho-xylene
solvent.
[0016] One embodiment, with reference to the polyamine component,
is that where R.dbd.R.sup.1, wherein R.sup.1 is an aliphatic
hydrocarbyl group of 4 to 24 carbon atoms, especially where R.sup.1
is the aliphatic hydrocarbyl group of tallowamine.
[0017] Also, with reference to the polyamine component, are
embodiments where R is R.sup.1NHR.sup.2, wherein R.sup.1 is an
aliphatic hydrocarbyl group of 8 to 22 carbon atoms and R.sup.2 is
an alkylene group of 3 carbon atoms, especially where R.sup.1 is
the aliphatic hydrocarbyl group of tallowamine.
[0018] In one aspect of the invention, a polysulfone copolymer of
the invention is 1-decene polysulfone having an molecular weight in
the range of 10,000 to 1,500,000 amu and in a particular aspect,
the polymeric polyamine is the polymeric 1:1.25 mol ratio reaction
product of N-tallow-1,3-diaminopropane with epichlorohydrin.
[0019] The weight ratio of polysulfone copolymer to polymeric
polyamine in the invention composition ranges from about 100:1 to
1:100, in one aspect from about 50:1 to 1:1, and in another aspect
from about 20:1 to 1:1.
[0020] This invention also concerns the two-component additive as
heretofore described together with a strong acid (oil-soluble
sulfonic acid is suitable). Thus, a polyamine-sulfonic acid salt
will be formed which has an improved resistance to
precipitate-formation during long storage periods. This invention
also concerns the additives in concentrate form in a solvent. One
composition containing the antistatic additive, an acid to enhance
precipitate-free storability, and a solvent, comprises, based on
total weight: [0021] i. from about 1 to 50 percent of the
polysulfone, prepared in an ortho xylene solvent, [0022] ii. from
about 1 to 50 percent of the polymeric polyamine, [0023] iii. from
about 1 to 30 percent of oil-soluble sulfonic acid, and [0024] iv.
from about 3 to 97 percent of solvent.
[0025] A suitable sulfonic acid (iii) is mono and di sulfonates of
alky benzenes, and in one aspect is dodecylbenzene sulfonic acid,
or dinonylnaphthyl sulfonic acid.
[0026] This invention also concerns a composition comprising a
liquid hydrocarbon fuel boiling in the range of from about
20.degree. to 375.degree. C., and from about 0.01 ppm to 40 ppm of
the two-component polysulfone-polyamine antistatic additive
composition and the additive composition stabilized with a strong
acid as described herein. Although more than 40 ppm of the additive
can be used, no significant benefit is thereby derived. The
additive composition can also be used in solvents, oils, and other
mixtures such as paints and other formulations where improved
conductivity is desired.
[0027] Certain co-additives which are known to provide good initial
electrical conductivity in cooperation with the polysulfone
copolymer component can also be included in the present invention
composition. Included are quaternary ammonium compounds which are
more fully described in coassigned U.S. Pat. No. 3,811,848 (the
entire teaching of which is herein incorporated in its entirety by
reference).
[0028] It has been found that improved three-component antistatic
compositions can be obtained by combining the polymeric polyamine
described herein with a two-component antistatic additive
comprising:
[0029] (i) a polysulfone copolymer prepared in ortho-xylene
comprising about 50 mol percent of units derived from sulfur
dioxide from about 40 to 50 mol percent of units derived from
1-alkene of 4 to 24 carbon atoms and from 0 to about 10 mol percent
of units derived from an olefin having the formula ##STR2## wherein
A is a group having the formula --(C.sub.xH.sub.2x)--COOH wherein x
is from about 0 to about 17, and B is hydrogen or carboxyl, with
the proviso that when B is carboxyl, x is 0, and wherein A and B
together can be a dicarboxylic anhydride group and
[0030] (ii) a quaternary ammonium compound having the formula:
##STR3## wherein Alk.sup.1 and Alk.sup.2 are the same or different
alkyl groups having from 1 to 22 carbon atoms, Alk.sup.3 is
selected from the group consisting of alkyl groups of 1 to 22
carbon atoms and ##STR4## where Alk.sup.3 is hydrogen or methyl and
n is 1 to 20, Alk.sup.4 is selected from the group consisting of
(a) an alkyl group having 1 to 22 carbon atoms, (b) an aralkyl
group having from 7 to 22 carbon atoms, (c) a ##STR5## group as
defined above, (d) a ##STR6## group wherein Alk.sup.6 and Alk.sup.7
are the same or different alkyl groups having from 11 to 19 carbon
atoms, and (e) an --Alk.sup.8--CO.sub.2 group wherein Alk.sup.8 is
a hydrocarbyl group having from 1 to 17 carbon atoms, with the
proviso that when Alk.sup.1, Alk.sup.2, Alk.sup.3 and Alk.sup.4 are
each alkyl groups, at least one of them is an alkyl group having at
least 8 carbon atoms,
[0031] A is an anion,
[0032] z is 0 or 1, z is 0 when Alk.sup.4 is (d) or (e), and
[0033] y is at least 1, y is equal to the ionic valence of anion A
when z is 1.
[0034] The ratio of the components are such that for each part of
polysulfone there is 0.01 to 100 parts of each of the polymeric
polyamine and the quaternary ammonium compound.
[0035] A suitable quaternary ammonium compound is dicocodimethyl
ammonium nitrite wherein "coco" refers to a mixture of C.sub.8 to
C.sub.18 alkyl radicals of cocoamine. The quaternary ammonium
compound can be present in the amounts of from about 1 part to 25
parts per 100 parts of polysulfone copolymer. The presence of a
quaternary ammonium compound further enhances the electrical
conductivity of the present invention composition in many
hydrocarbon fuels and maintains the composition ash-free.
[0036] Another embodiment of the present invention is directed to a
fuel oil composition. This fuel composition can comprise a suitable
fuel component and a suitable additive component. In one aspect,
the composition comprises from about 99.99% fuel and about 0.01% of
additive to about 99.9999% fuel to about 0.0001% of additive. A
suitable additive includes those described herein.
[0037] The term "hydrocarbyl" employed herein refers to straight
and branched-chain groups containing only carbon and hydrogen. Such
groups can be saturated, unsaturated or aromatic.
[0038] For a better understanding of the present invention,
together with other and further objects thereof, reference is made
to the accompanying drawings and detailed description and its scope
will be pointed out in the appended claims.
DETAILED DESCRIPTION OF THE INVENTION
The Polysulfones:
[0039] The polysulfone compolymers often designated as
olefin-sulfur dioxide copolymer, olefin polysulfones, or
poly(olefin sulfone) are polymers wherein the structure is
considered to be that of alternating copolymers of the olefins and
sulfur dioxide, having a one-to-one molar ratio of the comonomers
with the olefins in head to tail arrangement. The polysulfones used
in this invention are readily prepared by the methods known in the
art (cf. Encyclopedia of Polymer Science and Technology Vol. 9,
Interscience Publishers, page 460 etc, the entire teaching of which
is incorporated herein by reference).
[0040] The weight average molecular weights of the polysulfones are
in the range from about 10,000 to about 1,500,000, in one aspect
the range is from about 50,000 to about 900,000, and in another
aspect the molecular weights range from about 100,000 to about
500,000. Olefin polysulfones whose molecular weights are below
about 10,000, while effective in increasing conductivity in
hydrocarbon fuels, do not increase the conductivity values as much
as olefin polysulfones of higher molecular weights. Olefin
polysulfones whose molecular weights are above about 1,500,000 are
difficult to produce and are more difficult to handle.
[0041] The molecular weights of the olefin polysulfones can be
determined by any of the well-known methods, such as the light
scattering method. It is generally more convenient, however, to
determine the inherent viscosity of the polymer to derive the
approximate molecular weight range of the polysulfones therefrom.
Inherent viscosity is defined as .eta..sub.inh=ln..eta..sub.rel/C
wherein In is the natural logarithm, .eta..sub.rel is a relative
viscosity, i.e., ratio of the viscosity of the polymer solution to
the viscosity of the polymer solvent and C is concentration of
polymer g/100 mL. The units of inherent viscosity are deciliters
per gram (dl/g). The inherent viscosities of olefin poly-sulfones
are conveniently measured in toluene at 30.degree. C. as 0.5 weight
percent solutions. It has been found by comparison with molecular
weight determinations that polysulfones with inherent viscosities
of between about 0.1 dl/g to 1.6 dl/g correspond to weight average
molecular weights in the range of about 50,000 to 900,000.
[0042] The control of the molecular weights of the olefin
polysulfones in the desired range is readily accomplished by those
skilled in the art of polymer science by controlling the
polymerization conditions such as the amount of initiator used,
polymerization temperature and the like or by using molecular
weight modifiers such as dodecyl mercaptan. The amount of molecular
weight modifier required to obtain the desired molecular weight
range will depend upon the particular 1-olefin being polymerized
with sulfur dioxide, and can be determined easily with few
experiments. Generally, the amount of modifier, such as dodecyl
mercaptan, used to obtain the molecular weights in the range of
50,000 to 900,000 is in the range of up to about 0.007 mole per
mole of 1-olefin.
[0043] The 1-alkenes useful for the preparation of the polysulfones
are available commercially as pure or mixed olefins from petroleum
cracking processes or from the polymerization of ethylene to a low
degree. Included, but not limited to, are 1-hexene, 1-heptene,
1-octene, 1-nonene, 1-decene, 1-undecene, 1-dodecene, 1-tridecene,
1-tetradecene, 1-pentadecene, 1-hexadecene, 1-heptadecene,
1-octadecene, 1-nonodecene, 1-eicosene, 1-heneicosene, 1-docosene,
1-tricosene and 1-tetracosene. Poly unsaturated olefins such as
butadiene and its analogs, and branched olefins and internal
olefins are also utilizeable in the invention. Although
branched-chain alkenes are useful, the straight-chain 1-alkenes are
also useful whether pure or in admixture with other straight-chain
1-alkenes.
[0044] When the polysulfone copolymer contains up to 10 mol percent
of the olefin AHC.dbd.CHB, as defined above, A and B can together
form a dicarboxylic anhydride group. The dicarboxylic anhydride
group is readily converted to two carboxyl groups by simple acid
hydrolysis. The olefin, AHC.dbd.CH.sub.2, is a terminally
unsaturated alkenoic acid represented by
CH.sub.2.dbd.CH--(C.sub.xH.sub.2x)--COOH. The alkylene group
bridging the vinyl and the carboxyl groups can have from 1 to 24
carbon atoms or it can be absent, and such alkylene group when
present can be a straight chain group or branched chain. The useful
acids are alkenoic acids of 3 to 20 carbon atoms wherein the
olefinic group is a terminal group. Representative but nonlimiting
examples of alkenoic acids with a terminal olefinic group include
acrylic acid, 3-butenoic acid, 4-pentenoic acid, 5-hexenoic acid,
6-heptenoic acid, 7-octenoic acid, 8-nonenoic acid, 9-decenoic
acid, 10-undecenoic acid, 11-dodenoic acid, 13-tetradecenoic acid,
15-hexadecenoic acid, 17-octadecenoic acid as well as branched
chain alkenoic acids with terminal olefinic groups such as
2-ethyl-4-pentenoic acid, 2,2-dimethyl-4-pentenoic acid,
3-ethyl-6-heptenoic acid, 2-ethyl-6-heptenoic acid,
2,2-dimethyl-6-heptenoic acid, and the like. It should be
understood that a mixture of alkenoic acids can be used.
[0045] The reaction leading to polysulfone formation is the
art-known free-radical polymerization process. Nearly all types of
radical initiators are effective in initiaing polysulfone
formation. Radical initiators such as oxygen, ozonides,
t-butylperoxy-pivalate, hydrogen peroxide, ascaridole, cumene
peroxide, benzoyl peroxide, azobisisobutyronitrile are examples of
some of the useful initiators. Free-radicals are generated from
such radical initiators either thermally and/or by light activation
in the presence of a mixture of sulfur dioxide and 1-alkene. The
polymerization can be carried out in liquid phase, conveniently in
a solvent such as benzene, toluene or xylene to facilitate the
reaction. In one aspect of this invention, ortho-xylene
("o-xylene") is the solvent employed. Such solvent can be removed,
e.g., by distillation, if desired, but it is generally more the
convenient to use the polysulfone copolymer as a concentrate in
such solvent. Generally, it is typical to use an excess of sulfur
dioxide since any unreacted sulfur dioxide is readily removed as by
passing nitrogen gas into the polymer solution. An exess of
1-alkene can be used, however, and the excess subsequently removed
as by distillation.
[0046] Using ortho-xylene has several advantages. For example, the
use of o-xylene as a solvent leads to increased conductivity, an
increase of approximately 15% was observed when o-xylene was used
(See Tables I and II, infra.) Ortho-xylene also facilitates the
removal of toxins, e.g., ethyl benzene. One also observes an
increase in flash point using o-xylene, as compared to tolene. This
is mainly due to the difference in the flash points between
o-xylene (86.degree. C.) and Toluene (40.degree. C.) TABLE-US-00001
TABLE I Comparison of the conductivity enhancement of a Static
Dissipater formulation where the poly Sulfone polymer in the
formulation was prepared in o-xylene, to that which was prepared in
Toluene. Formulation Conductivity pS/m Conductivity pS/m 1 PSI
w/o-xylene 369 425 2 PSI w/o-xylene 342 388 3 PSI w/toluene 303
345
[0047] TABLE-US-00002 TABLE II Conductivity of a Static Dissipater
formulations where the poly Sulfone polymer in the formulation was
prepared in Toluene. Formulation Conductivity 1 361 pS/m 2 338 pS/m
3 287 pS/m 4 347 pS/m 5 296 pS/m 6 274 pS/m 7 272 pS/m 8 242 pS/m 9
300 pS/m
[0048] The particular ratio of 1-alkene to sulfur dioxide appears
to be immaterial since the resultant polysulfone copolymer contains
1-alkene and sulfur dioxide in 1:1 molar ratio regardless of the
particular ratio used. However, for efficiency in utilization of
the reactants and of the equipment, a slight excess of sulfur
dioxide is often employed. The polymerization can be carried out at
atmospheric or super-atmospheric pressures, the polymerization
reaction being independent of the pressure. The polymerization
temperature can be any convenient temperature below the ceiling
temperature of the particular 1-alkene employed. Ceiling
temperature is the temperature at which the rates of polymerization
and depolymerization are equal so that no polymer formation takes
place. The above mention "Encyclopedia of Polymer Science and
Technology" on page 466 lists ceiling temperatures for various
1-alkenes. Generally, the convenient polymerization temperature
range is from about 0.degree. to about 50.degree. C.
The Polymeric Polyamines:
[0049] The polyamine component of the antistatic composition of the
present invention is a polymeric reaction product of
epichlorohydrin with an aliphatic primary monoamine or N-aliphatic
hydrocarbyl alkylene diamine. The polymeric reaction products are
prepared by heating an amine with eipchlorohydrin in the molar
proportions of from about 1:1-1.5 in the temperature range of about
50.degree. to about 100.degree. C. Generally, with aliphatic
monoamines, R.sup.1NH.sub.2, the molar ratio is about 1:1. The
initial reaction product is believed to be an addition product as
illustrated below with a primary momoamine, R.sup.1NH.sub.2,
##STR7##
[0050] The aminochlorohydrin (I) upon reaction with an inorganic
base then forms an aminoepoxide. ##STR8##
[0051] The aminoepoxide (II), which contains a reactive epoxide
group and a reactive amino-hydrogen, undergoes polymerization to
provide a polymeric material containing several amino groups. The
ratio of epichlorohydrin to amine and the reaction temperature used
are such that the polymeric reaction product contains from 1 to 20
recurring units derived from the aminoepoxide represented by
II.
[0052] The polymeric reaction product derived from epichlorohydrin
and an aliphatic primary monoamine as defined is represented by
subgeneric formula (A), ##STR9##
[0053] where a is an integer from 1 to 20 and x is an integer of 1
to 2.
[0054] The aliphatic primary monoamines that can be used to prepare
the polymeric reaction products with epichlorohydrin can be
straight chain or branched chain and include, inter alia,
octylamine, nonylamine, decylamine, undecylamine, dodecylamine,
tridedecylamine, tetadecylamine, pentadecylamine, hexadecylamine,
heptadecylamine, octdadecylamine, nonadecylamine, eicosylamine,
heneicosylamine, docosylamine, tricosylamine, tetracosylamine and
the corresponding alkenyl analogs. The aliphatic primary amine
should have at least about 4 carbon atoms, in one aspect, about 12
to 24 carbon atoms to provide polymeric reaction products of
sufficient solubility in hydrocarbon fuels. While aliphatic primary
amines containing more than about 24 carbon atoms are useful, such
amines are of limited availability.
[0055] Mixtures of aliphatic primary amines can also be used, and
are typical since mixtures of primary amines derived from tall oil,
tallow, soybean oil, coconut oil, cotton seed oil and other oils of
vegetable and animal origin are commercially available and at lower
cost than individual amines. The above mixtures of amines generally
contain alkyl and alkenyl amines of from about 12 to 18 carbon
atoms, although sometimes an individual amine mixture, depending
upon the source, contains small amounts of primary amines having
fewer or more carbon atoms. An example of a commercially available
mixture of primary monoamines is hydrogenated tallow amine which
contains predominantly hexadecyl- and octadecylamines with smaller
amounts of tetradecylamine.
[0056] When the amine reacted with epichlorohydrin is an
N-hydrocarbylalkyl-enediamine as defined, the polymeric reaction
product is represented by subgeneric formula (B), ##STR10##
[0057] where R.sup.1 is an aliphatic hydrocarbyl group of 4 to 24
carbon atoms, R.sup.2 is an alkylene group of 2 to 6 carbon atoms,
b and c are integers of 0 to 20 and b+c is an integer of 2 to 20
and x is 1 to 2.
[0058] In the reaction of epichlorohydrin with an N-aliphatic
hydrocarbylalkyl-enediamine, it is believed (because of the known
greater reactivity of primary amino hydrogen over secondary amino
hydrogen) that the initially formed aminochlorohydrin is of the
formula ##STR11## and the subsequently formed aminoepoxide is of
the formula ##STR12##
[0059] When IIa undergoes further condensation, the recurring units
in the product may be ##STR13## or both, since (IIa) contains two
reactive secondary aminohydrogens. Thus, in subgeneric formula (B),
above, b is from 0 to 20, c is from 0 to 20 and b+c is from 2 to
20.
[0060] Illustrative examples of useful N-aliphatic hydrocarbyl
alkylene diamines include, but not limited to, N-octyl, N-nonyl,
N-decyl, N-undecyl, N-dodecyl, N-tridecyl, N-tetradecyl,
N-pentadecyl, N-hexadecyl, N-heptadecyl, N-octadecyl, N-nonadecyl,
N-eicosyl, N-uneicosyl, N-docosyl, N-tricosyl, N-tetracosyl, as
well as the corresponding N-alkenyl derivatives of ethylenediamine,
propylenediamine, butylenediamine, pentylenediamine and
hexylenediamine. In one aspect, the N-aliphatic
hydrocarbyl-alkylenediamine is N-aliphatic
hydrocarbyl-1,3-propylenediamine. The N-aliphatic
hydrocarbyl-1,3-propylenediamines are commercially available and
are readily prepared from aliphatic primary monoamines such as
those described above by cyanoethylation with acrylonitrile and
hydrogenation of the cyanoethylated amine. Mixtures of N-aliphatic
hydrocarbyl-1,3-propylenediamines can also be advantageously used.
A typical mixture is N-tallow-1,3-propylenediamine which is
commercially available as "Duomeen T" wherein "tallow" represents
predominantly mixtures of alkyl and alkenyl groups of 16 to 18
carbon atoms which can contain small amounts of alkyl and alkenyl
groups of 14 carbon atoms.
[0061] The reaction between the amines (as defined) and
epichlorohydrin is advantageously carried out in the presence of a
solvent such as benzene, toluene, xylene, ortho-xylene, or other
higher boiling mixtures of aromatic solvents, such as Aromatic 100
or Aromatic 150 which can also contain some hydroxylic component
such as ethanol, propanol, butanol and the like.
[0062] After the initial reaction between the amine and
epichlorohydrin to form an aminochlorohydrin intermediate as
illustrated above by Products I and Ia, the reaction mass is
treated with an inorganic base, such as sodium, potassium or
lithium hydroxide, to form an aminoepoxide as represented by
Products II and IIa above, which under continued heating undergoes
polymerization to yield the desired product represented above by
the generic formula and subgenerics A and B. Inorganic chloride
formed in the reaction is removed by filtration. The solvent used
to facilitate the reaction can be removed if desired, e.g., by
distillation, but generally it is more convenient to use the
polymeric polyamine as a solution.
[0063] The above-described reactions of epichlorohydrin with amines
to form polymeric products are well known and find extensive use in
epoxide resin technology (cf. "Epoxy Resins", Henry Lee and Kris
Neville, The McGraw-Hill Book Co., 1957, the entire teaching of
which is incorporated herein by reference). The polymeric reaction
products of epichlorohydrin and amines are complex mixtures but it
is believed that the above formulas of the polymeric polyamines
fairly represent the composition and structures that are
obtained.
[0064] The normally liquid hydrocarbon fuels to which the additives
are added to render such hydrocarbon fuels electrically conductive
are those boiling in the range of about 20.degree. to about
375.degree. C. and include such commonly designated fuels as
aviation gasoline, motor gasoline, jet fuels, naphtha, kerosene,
diesel fuel and distillate burner fuel oil. The additive
composition can be added in any conventional manner. Each
individual component of the composition can be added to the
hydrocarbon fuel separately or the composition can be added as a
simple mixture or as a solution in a solvent, such as benzene,
toluene, xylene, o-xylene, isopropanol, cyclohexane, Aromatic 100
and Aromatic 150 fuel oil, or in a mixture of such solvents. It is
convenient to prepare both the polysulfone copolymer and the
polymeric polyamine in a solvent, such as one or more of those
mentioned above. Thus, it is typical to use such solutions of
polysulfone and polymeric polyamine and to combine them. The
combination, which can be termed a concentrate, can then be added
to the hydrocarbon fuel. Such concentrate conveniently contains
from about 1 to 40% by weight of polysulfone copolymer, from about
1 to about 40% by weight of polymeric polyamine and from about 20
to 98% by weight of a solvent or a mixture thereof as described. In
one aspect, the concentrate will contain from about 5 to 25% by
weight of polysulfone copolymer, from about 5 to 25% by weight of
polymeric polyamine and from about 50 to 90% by weight of
solvent.
[0065] When formulating concentrates, it is typical that the
polymeric polyamine be present as a salt, particularly a sulfonic
acid salt, for improved resistance to precipitate formation in
storage. For example, when a concentrate as described comprising
polymeric polyamine in the free base form is stored at elevated
temperatures of about 44.degree. C. for a period of time of about 4
weeks, a small amount of precipitate sometimes forms. The presence
of small amounts of precipitate in the concentrates have little or
no effect on the usefulness of the present compositions as
antistatic additives but are undesirable if only from an aesthetic
point of view. It has been found that strong acids such as
hydrochloric, sulfuric or a sulfonic acid can be used to limit
precipitate formation in the concentrates. Oil-soluble sulfonic
acids are typical because they effectively inhibit precipitate
formation without substantial deleterious effect upon the
electrical conductivity property of the composition. Any
oil-soluble sulfonic acid such as an alkanesulfonic acid or an
alkarysulfonic acid can be used. A useful sulfonic acid is
petroleum sulfonic acid resulting from treating oils with sulfuric
acid.
[0066] Generally, the amount of sulfonic acid incorporated in the
concentrate is an equivalent amount, that is, sufficient amount of
sulfonic acid to neutralize all the amine groups of the polymeric
polyamine, although lesser or greater than the equivalent amount
can be used. Thus, one form of the concentrate of the present
invention will contain from about 5 to 25% by weight of polysulfone
copolymer, from about 5 to 30% by weight of polymeric polyamines,
from about 5 to 30% by weight of, say, dodecylbenzenesulfonic acid,
and from about 20 to 85% by weight of solvent. Typically an
equivalent amount of dodecylbenzenesulfonic acid or dinonylnaphthyl
sulfonic acid is used.
[0067] When a three-component additive is employed (where a
quaternary ammonium compound is the third component), the
concentrate composition will comprise, based on total weight of the
composition: from about 5 to 25% of polysulfone, from about 5 to
25% of polyamine, from about 0.5 to 5% of quaternary ammonium
compound, from about 5 to 25% of a sulfonic acid, say,
dodecylbenzene sulfonic acid, and from about 20 to 84.5% of
solvent.
[0068] The utility of the present invention composition as a highly
effective antistatic additive for hydrocarbon fuels is demonstrated
by the fact that the incorporation into hydrocarbon fuels of as
little as 0.00003% by weight (0.3 part per million, ppm) of
polysulfone copolymer and 0.00002% by weight (0.2 ppm) of polymeric
polyamine is sufficient, in nearly all hydrocarbon fuels
investigated, to provide electrical conductives of at least 100
C.U. (conductivity units). In certain responsive fuels, as little
as 0.0000018 weight % (0.018 ppm) polysulfone copolymer and
0.0000013 weight % (0.013 ppm) polymeric polyamine provide a
conductivity of at least 100 C.U. Thus, the present invention
provides a highly effective ashless antistatic additive composition
which confers increased electrical conductivity to hydrocarbon
fuels at very low usage levels.
[0069] The antistatic effectiveness of the present invention
composition is unexpected as the polysulfone product prepared in
o-xylene and the correspondent composition derived from said
polysulfone is superior to a similar composition derived from
polysulfone prepared from toluene.
[0070] The hydrocarbon fuels into which the present composition is
incorporated exhibit satisfactory water interaction properties as
evidenced by satisfactory results in the water separation test
according to ASTM D-2250-66T. The hydrocarbon fuel composition
containing the composition of the invention can also contain
conventional additives used in hydrocarbon fuels such as antiknock
compounds, antioxidants, corrosion inhibitors, metal deactivators,
rust preventatives, dyes, anti-icing agents and the like.
[0071] The polysulfones, and poly amines evaluated in the present
invention were prepared according to procedures outlined in U.S.
Pat. No. 3,917,466. The examples cited therein are not intended to
be a limit of the scope of the invention.
[0072] Another embodiment of the present invention is directed to a
fuel oil composition. This fuel oil composition can comprise a
suitable fuel oil component and a suitable additive component. In
one aspect, the composition comprises from about 99.99% fuel and
about 0.01% additive to about 99.9999% fuel to about 0.0001%
additive. In one aspect, a suitable additive includes those
described herein. The fuel oil can be a petroleum-based fuel oil,
suitably a gasoline or middle distillate fuel oil. The fuel oils
can comprise atmospheric or vacuum distillate, contain cracked gas
oil in or a blend of any proportion of straight run or thermally or
catalytically cracked distillates, and in many cases are
hydrogen-treated or otherwise processed to improve properties.
[0073] Gasolines are low boiling mixtures of aliphatic, olefinic,
and aromatic hydrocarbons, and optionally alcohols or other
oxygenated components, boiling in the range from room temperature
up to 225.degree. C. Other fuel oils are kerosine, jet fuels,
diesel fuel oils and home heating fuel oils (such as, middle
distillate heating fuels), generally having flash points greater
than 380.degree. C. These fuels are higher boiling mixtures of
aliphatic, olefinic, and aromatic hydrocarbons having a boiling
point up to 350.degree. C.
[0074] Conductivity of fuels and solvents comprising static
dissipators are commonly measured using ASTM D 2624 or IP 274, a
technically equivalent method. See, ASTM D 2624-02, the entire
teaching of which is incorporated herein by reference. For
comparative purposes, compositions can be tested according to the
method described in ASTM in fuels, or in a standard solvent such as
Isopar M. Isopar M is a high-flash solvent marketed by Exxon Mobil
and is highly paraffinic. Results from testing in this solvent are
directionally similar to those obtained in fuels such as motor
gasoline, aviation gasoline, aviation turbine fuel, diesel fuels of
various sulfur contents, and home heating fuels.
[0075] Although the invention has been described with respect to
various embodiments, it should be realized this invention is also
capable of a wide variety of further and other embodiments within
the spirit and scope of the appended claims.
* * * * *