U.S. patent application number 10/581042 was filed with the patent office on 2007-05-03 for fuel oil compositions with improved cold flow properties.
This patent application is currently assigned to Basf Aktiengesellschaft. Invention is credited to Wolfgang Ahlers, Ansgar Eisenbeis, Andreas Fechtenkotter, Frank-Olaf Mahling, Irene Trotsch-Schaller.
Application Number | 20070094920 10/581042 |
Document ID | / |
Family ID | 37994460 |
Filed Date | 2007-05-03 |
United States Patent
Application |
20070094920 |
Kind Code |
A1 |
Ahlers; Wolfgang ; et
al. |
May 3, 2007 |
Fuel oil compositions with improved cold flow properties
Abstract
The use is described of polymers which contain, in copolymerized
form, an .alpha.-olefin, a vinyl ester and an ester of an
.alpha.,.beta.-unsaturated carboxylic acid as an additive for fuel
oils and lubricants and in particular as a cold flow improver in
fuel oils. In addition, the fuel oils and lubricants additized with
these polymers; and also additive packages comprising such polymers
are described.
Inventors: |
Ahlers; Wolfgang; (Worms,
DE) ; Fechtenkotter; Andreas; (Ludwigshafen, DE)
; Mahling; Frank-Olaf; (Mannheim, DE) ;
Trotsch-Schaller; Irene; (Bissersheim, DE) ;
Eisenbeis; Ansgar; (Weisenheim am Berg, DE) |
Correspondence
Address: |
OBLON, SPIVAK, MCCLELLAND, MAIER & NEUSTADT, P.C.
1940 DUKE STREET
ALEXANDRIA
VA
22314
US
|
Assignee: |
Basf Aktiengesellschaft
LUDWIGSHAFEN
GERM ANY
DE
D-76056
|
Family ID: |
37994460 |
Appl. No.: |
10/581042 |
Filed: |
December 3, 2004 |
PCT Filed: |
December 3, 2004 |
PCT NO: |
PCT/EP04/13781 |
371 Date: |
December 19, 2006 |
Current U.S.
Class: |
44/393 |
Current CPC
Class: |
C10M 2209/084 20130101;
C10L 10/16 20130101; C10L 1/1973 20130101; C10N 2030/08 20130101;
C10L 10/14 20130101; C10M 145/14 20130101 |
Class at
Publication: |
044/393 |
International
Class: |
C10L 1/18 20060101
C10L001/18 |
Claims
1. The use of a polymer which contains, in copolymerized form, an
.alpha.-olefin, a vinyl ester and an ester of an
.alpha.,.beta.-unsaturated carboxylic acid as an additive for fuel
oils and lubricants.
2. The use according to claim 1, wherein the polymer contains the
vinyl ester and the ester of an .alpha.,.beta.-unsaturated
carboxylic acid copolymerized in random distribution.
3. The use according to any of the preceding claims, wherein the
polymer is composed of monomers including M1, M2 and M3 and wherein
M1, M2 and M3 have the following general formulae: ##STR5## where
R.sup.1 is H or C.sub.1-C.sub.40-hydrocarbyl; R.sup.2, R.sup.3 and
R.sup.4 are each independently H or C.sub.1-C.sub.4-alkyl; R.sup.5
is C.sub.1-C.sub.20-hydrocarbyl; R.sup.6, R.sup.7 and R.sup.8 are
each independently H or C.sub.1-C.sub.4-alkyl; and R.sup.9 is
C.sub.1-C.sub.20-hydrocarbyl.
4. The use according to claim 3, wherein the monomers M1, M2 and M3
are present in the polymer in the following molar proportions: M1:
from 0.60 to 0.98 M2: from 0.01 to 0.20 M3: from 0.01 to 0.20.
5. The use according to either of claims 3 and 4, wherein monomer
M1 is ethylene.
6. The use according to any of claims 3 to 5, wherein R.sup.2,
R.sup.3 and R.sup.4 are each H or two of the R.sup.2, R.sup.3 and
R.sup.4 radicals are each H and the other radical is methyl.
7. The use according to any of claims 3 to 6, wherein R.sup.5 is
C.sub.1-C.sub.9-hydrocarbyl.
8. The use according to claim 7, wherein R.sup.5 is n-butyl or
2-ethylhexyl.
9. The use according to any of claims 6 to 8, wherein M2 is n-butyl
acrylate or 2-ethylhexyl acrylate.
10. The use according to any of claims 3 to 9, wherein M3 is vinyl
acetate.
11. The use according to any of the preceding claims, wherein the
polymer is used as a cold flow improver.
12. A fuel oil composition comprising a major proportion by weight
of a middle distillate fuel boiling in the range of 120-500.degree.
C. and a small proportion by weight of at least one polymer as
defined in any of claims 1 to 11.
13. The fuel oil composition according to claim 12, wherein the
fuel component comprises biodiesel (from animal or vegetable
production) in proportions of 0-100% by weight.
14. The fuel oil composition according to claim 12, selected from
diesel fuels, kerosene and heating oil.
15. The fuel oil composition according to claim 14, wherein the
diesel fuel is obtainable by refining, coal gasification or gas
liquefaction, or is a mixture of such products and is optionally
mixed with renewable fuels.
16. The fuel oil composition according to any of claims 12 to 15,
wherein the sulfur content of the mixture is at most 500 ppm.
17. A lubricant composition comprising a major proportion by weight
of a conventional lubricant and a minor proportion by weight of at
least one polymer as defined in any of claims 1 to 10.
18. The use or composition according to any of the preceding
claims, wherein the polymer is used in combination with further
conventional cold flow improvers and/or further lubricant and fuel
oil additives.
19. An additive package comprising at least one polymer as defined
in any of claims 1 to 10 in combination with at least one further
conventional lubricant or fuel oil additive.
Description
DESCRIPTION
[0001] The invention relates to the use of polymers which contain,
in copolymerized form, an .alpha.-olefin, a vinyl ester and an
ester of an .alpha.,.beta.-unsaturated carboxylic acid as an
additive for fuel oils and lubricants and in particular as a cold
flow improver in fuels; to the fuel oils and lubricants additized
with these polymers; and to additive packages comprising such
polymers.
PRIOR ART
[0002] On temperature reduction, mineral oils comprising paraffinic
waxes, such as middle distillates, diesel and heating oils, exhibit
a distinct deterioration in the flow properties. The cause of this
is the crystallization occurring from the cloud point temperature
of relatively long-chain paraffins which form large,
platelet-shaped wax crystals. These wax crystals have a spongelike
structure and lead to inclusion of other fuel constituents in the
crystal structure. The occurrence of these crystals leads rapidly
to clogging of fuel filters both in tanks and in motor vehicles. At
temperatures below the pour point (PP) the fuel eventually does not
flow at all.
[0003] To alleviate these problems, fuel additives, which
frequently consist of combinations of nucleators for early
formation of very small crystals of the paraffins with the actual
cold flow improvers (also known as CFI or MDFI), have already been
added in small concentrations for some time. These in turn exhibit
similar crystallization properties to the paraffins of the fuel,
but prevent their growth, so that it is possible for it to pass
through the filter at distinctly lower temperatures compared to the
unadditized fuel. The cold filter plugging point (CFPP) is
determined as a measure thereof. Further additives which can be
used are wax antisettling additives (WASA), which prevent the
settling of the very small crystals in the fuel.
[0004] Depending on the composition of the base fuel and of the
additive, cold flow improvers are added in amounts of from about 50
to 500 ppm. The prior art discloses various CFI products (cf., for
example, U.S. Pat. Nos. 3,038,479, 3,627,838 and 3,961,961,
EP-A-0,261,957 or DE-A-31 41 507 and 25 15 805). Common CFIs are
usually polymeric compounds, in particular ethylene-vinyl acetate
(EVA) copolymers, for example the products sold by BASF AG under
the tradename Keroflux.
[0005] Combinations of conventional CFIs with lubricity improvers
(esters of mono- or polycarboxylic acids with mono- or
polyalcohols) are also described as improved CFI combinations
(EP-A-0 721 492).
[0006] EP 0922716 describes a process for preparing terpolymers
which, in addition to ethylene, contain, in copolymerized form, at
least two further ethylenically unsaturated compounds such as vinyl
esters, acrylic or methacrylic esters, alkyl vinyl ethers or higher
olefins. These are said to be suitable as flow point improvers of
mineral oil distillates.
[0007] DE 1902925 describes terpolymers which contain, in
copolymerized form, ethylene, vinyl esters of short-chain
carboxylic acids, such as vinyl acetate, and long-chain unsaturated
monoesters, such as vinyl esters of long-chain carboxylic acids, or
acrylic esters which derive from long-chain alcohols. These are
said to lower the pour point of middle distillates and improve
their filterability.
[0008] U.S. Pat. No. 4,156,434 describes terpolymers which, in
addition to ethylene and vinyl acetate, contain, in copolymerized
form, an acrylic ester which derives from
C.sub.12-C.sub.24-alcohols. These are said to lower the pour point
of gas oils. No filterability-improving action is described.
[0009] There is a continuing need for further additives having CFI
properties, especially those which are less expensive to use, for
example because they improve the cold flow properties of fuel oils
or lubricants and especially the filterability of fuel oils in
lower dosage than commercial CFIs.
BRIEF DESCRIPTION OF THE INVENTION
[0010] It is accordingly an object of the present invention to
provide novel such additives.
[0011] Surprisingly, this object is achieved by the unexpected
observation that polymers which contain, in copolymerized form, an
.alpha.-olefin, a vinyl ester and an ester of an
.alpha.,.beta.-unsaturated carboxylic acid can be used as CFI
additives and also have better performance than conventional
EVA-CFIs.
[0012] The invention accordingly relates firstly to the use of a
polymer which contains, in copolymerized form, an .alpha.-olefin, a
vinyl ester and an ester of an .alpha.,.beta.-unsaturated
carboxylic acid as an additive for fuel oils and lubricants. In
particular, the polymers used are those which contain the vinyl
ester and the ester of the .alpha.,.beta.-unsaturated carboxylic
acid copolymerized in random distribution. The polymer is
preferably a terpolymer which is composed substantially of the
three aforementioned monomers.
[0013] Preference is given to using polymers which are composed of
monomers including the monomers M1, M2 and M3, where M1, M2 and M3
have the following general formulae ##STR1## where [0014] R.sup.1
is H or C.sub.1-C.sub.40-hydrocarbyl, for example
C.sub.1-C.sub.20-, in particular C.sub.1-C.sub.10-, preferably
C.sub.1-C.sub.4-hydrocarbyl; [0015] R.sup.2, R.sup.3 and R.sup.4
are each independently H or C.sub.1-C.sub.4-alkyl; [0016] R.sup.5
is C.sub.1-C.sub.20-hydrocarbyl; [0017] R.sup.6, R.sup.7 and
R.sup.8 are each independently H or C.sub.1-C.sub.4-alkyl; and
[0018] R.sup.9 is C.sub.1-C.sub.20-hydrocarbyl.
[0019] The monomers M1, M2 and M3 may be present in the polymers
used in accordance with the invention in the following molar
proportions (M.times./(M1+M2+M3) in the polymer:
[0020] M1: from 0.60 to 0.98, preferably from 0.7 to 0.95, in
particular from 0.8 to 0.9;
[0021] M2: from 0.01 to 0.20, preferably from 0.015 to 0.17, in
particular from 0.02 to 0.16;
[0022] M3: from 0.01 to 0.20, preferably from 0.02 to 0.15, in
particular from 0.03 to 0.1, especially from 0.03 to 0.09.
[0023] R.sup.1 is preferably H, methyl or ethyl and in particular
H; in other words, the monomer M1 is preferably ethylene, propene
or 1-butene and in particular ethylene.
[0024] In the monomer M2, the R.sup.2, R.sup.3 and R.sup.4 radicals
are preferably each H or methyl. More preferably, two of the
R.sup.2, R.sup.3 and R.sup.4 radicals are each H and the other
radical is H or methyl. In particular, all three R.sup.2, R.sup.3
and R.sup.4 radicals are H.
[0025] R.sup.5 is preferably C.sub.1-C.sub.12-hydrocarbyl,
particularly preferably C.sub.1-C.sub.10-hydrocarbyl, more
preferably C.sub.1-.sub.9-hydrocarbyl and even more preferably
C.sub.4-C.sub.8-hydrocarbyl. Hydrocarbyl is preferably alkyl. In
particular, R.sup.5 is n-butyl, 2-ethylhexyl or lauryl, of which
even greater preference is given to n-butyl and 2-ethylhexyl and
especially 2-ethylhexyl.
[0026] The monomer M2 is preferably selected from n-butyl acrylate,
2-ethylhexyl acrylate and lauryl acrylate and more preferably from
n-butyl acrylate and 2-ethylhexyl acrylate. In particular, it is
2-ethylhexyl acrylate.
[0027] In the monomer M3, R.sup.6, R.sup.7 and R.sup.8 are each
independently preferably H or methyl and more preferably H.
[0028] R.sup.9 is preferably C.sub.1-C.sub.10-hydrocarbyl.
Hydrocarbyl is preferably alkyl. R.sup.9 is more preferably ethyl
or methyl and in particular methyl.
[0029] The monomer M3 is more preferably vinyl acetate.
[0030] The polymers used in accordance with the invention are
preferably obtainable by, preferably free-radical, polymerization,
especially high-pressure polymerization, of the monomers M1, M2 and
M3.
[0031] Polymers used with preference are selected from
ethylene/n-butyl acrylate/vinyl acetate polymers,
ethylene/2-ethylhexyl acrylate/vinyl acetate polymers and
ethylene/lauryl acrylate/vinyl acetate polymers, and particular
preference is given to the two first-mentioned polymers. In
particular, ethylene/2-ethylhexyl acrylate/vinyl acetate polymers
are used.
[0032] Preference is given to using the polymers as cold flow
improvers.
[0033] The above-described polymers are used alone or in
combination with other such polymers in amounts which are
sufficient to exhibit action as a cold flow improver in the
additized fuel or lubricant.
[0034] The invention further provides fuel oil compositions
comprising a major proportion by weight of a middle distillate fuel
boiling in the range of about 120-500.degree. C. and a minor
proportion by weight of at least one polymer used in accordance
with the invention (cold flow improver) as defined above.
[0035] Such fuel oil compositions may also include, as a fuel
component, biodiesel (from animal and/or vegetable production) in
proportions of 0-100% by weight, preferably of from 0 to 30% by
weight.
[0036] Preferred fuel oil compositions are selected from diesel
fuels, kerosene and heating oil, and the diesel fuel may be
obtainable by refining, coal gasification or gas liquefaction, or
may be a mixture of such products and may optionally be mixed with
renewable fuels. Preference is given to those fuel oil compositions
in which the sulfur content of the mixture is preferably at most
500 ppm.
[0037] The invention further provides lubricant compositions
comprising a major proportion by weight of a conventional lubricant
and a minor proportion by weight of at least one polymer as defined
above.
[0038] In the context of the present invention, the polymers used
in accordance with the invention may be used in combination with
further conventional cold flow improvers and/or further lubricants
and fuel oil additives.
[0039] The invention finally also relates to additive packages
comprising at least one polymer used in accordance with the
invention as defined above in combination with at least one further
conventional lubricant and fuel oil additive.
DETAILED DESCRIPTION OF THE INVENTION
a) Polymers Used in Accordance with the Invention
[0040] The polymers used in accordance with the invention are
preferably composed substantially of the above-defined monomers M1,
M2 and M3. As a result of the preparation, small traces of a
compound used as a regulator (chain terminator) may in some cases
be present.
[0041] When no other information is given, the following general
definitions apply:
[0042] C.sub.1-C.sub.40-Hydrocarbyl is in particular
C.sub.1-C.sub.40-alkyl such as methyl, ethyl, n-propyl, isopropyl,
n-butyl, sec-butyl, isobutyl, tert-butyl, pentyl, hexyl, heptyl,
octyl, 2-ethylhexyl, nonyl, decyl, undecyl, dodecyl, tridecyl,
tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecyl,
nonadecyl, eicosyl, hencosyl, docosyl, tricosyl, tetracosyl,
pentacosyl, hexacosyl, heptacosyl, octacosyl, nonacosyl, squalyl
and the higher homologs and the corresponding positional isomers.
The same applies to C.sub.1-C.sub.20-hydrocarbyl radicals.
C.sub.1-C.sub.9-Hydrocarbyl is in particular C.sub.1-C.sub.9-alkyl
such as methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl,
isobutyl, tert-butyl, pentyl, neopentyl, hexyl, heptyl, octyl,
neooctyl, 2-ethylhexyl, nonyl and neononyl.
C.sub.1-C.sub.10-Hydrocarbyl is additionally in particular also
decyl and neodecyl. C.sub.4-C.sub.8-Hydrocarbyl is in particular
C.sub.4-C.sub.8-alkyl such as n-butyl, sec-butyl, isobutyl,
tert-butyl, pentyl, hexyl, heptyl, octyl and 2-ethylhexyl.
[0043] Examples of suitable monomers M1 include: monoalkenes having
nonterminal or preferably terminal double bond, in particular
ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene,
1-octene, 1-nonene and 1-decene, and also the higher
monounsaturated homologs having up to 40 carbon atoms.
[0044] Examples of preferred .alpha.,.beta.-unsaturated carboxylic
esters M2 include: acrylic esters of C.sub.1-C.sub.20-alkanols,
such as methyl acrylate, ethyl acrylate, propyl acrylate, isopropyl
acrylate, n-butyl acrylate, isobutyl acrylate, tert-butyl acrylate,
n-pentyl acrylate, neopentyl acrylate, hexyl acrylate, heptyl
acrylate, octyl acrylate, neooctyl acrylate, 2-ethylhexyl acrylate,
nonyl acrylate, neononyl acrylate, decyl acrylate, neodecyl
acrylate, lauryl acrylate, palmityl acrylate and stearyl acrylate;
also the corresponding methacrylic, crotonic and isocrotonic
esters, of which the acrylates (acrylic esters) are preferred.
Examples of Suitable Monomers M3 Include:
[0045] vinyl C.sub.1-C.sub.20-carboxylates, especially the vinyl
esters of acetic acid, propionic acid, butyric acid, valeric acid,
isovaleric acid, pivalic acid, caproic acid, enanthic acid,
caprylic acid, pelargonic acid, neononanoic acid, neodecanoic acid,
capric acid, lauric acid, myristic acid, palmitic acid, stearic
acid and arachic acid; also the corresponding propenyl esters.
However, preference is given to the vinyl esters.
[0046] The inventive polymers also have a number-average molecular
weight M.sub.n in the range from about 1000 to 20 000, more
preferably from 1000 to 10 000, in particular from 1500 to 6000 and
especially from 1500 to 5000.
[0047] The polymers may also have a weight-average molecular weight
M.sub.w of from 1000 to 30 000, in particular from 2000 to 20 000,
and/or an M.sub.w/M.sub.n ratio of from 1.5 to 5.0, preferably from
1.8 to 4.0 and in particular from 1.9 to 3.5.
[0048] Particularly preferred polymers are composed of the monomers
ethylene, vinyl acetate and an acrylic ester monomer which is
selected from n-butyl acrylate, 2-ethylhexyl acrylate and lauryl
acrylate and preferably from n-butyl acrylate and 2-ethylhexyl
acrylate. In particular, the acrylic ester monomer is 2-ethylhexyl
acrylate.
[0049] Based on a polymer composed of ethylene, 2-ethylhexyl
acrylate (EHA) and vinyl acetate (VAC), the proportion by weight of
the monomers is: [0050] EHA: 4-80% by weight, preferably from 5 to
62% by weight, in particular from about 7 to 45% by weight [0051]
VAC: 1-42% by weight, preferably from 1 to 30% by weight, in
particular from about 1 to 25% by weight, especially from 1 to 20%
by weight
[0052] The viscosity of such polymers (determined to Ubbelohde DIN
51562) is from about 5 to 25 000 mm.sup.2/s, preferably from about
10 to 1000 mm.sup.2/s, in particular from about 50 to 700
mm.sup.2/s, in each case at a temperature of about 120.degree.
C.
b) Preparation of the Polymers
[0053] The inventive polymers are prepared by processes known per
se, preferably by the processes known from the prior art (cf., for
example, Ullmann's Encyclopedia of Industrial Chemistry, 5th
Edition, "Waxes", Vol. A 28, p.146 ff., VCH, Weinheim, Basle,
Cambridge, New York, Tokyo, 1996; also U.S. Pat. No. 3,627,838;
DE-A 2515805; DE-A 3141507; EP-A 0007590) for direct, free-radical,
high-pressure copolymerization of unsaturated compounds.
[0054] The copolymers are preferably prepared in stirred
high-pressure autoclaves or in high-pressure stirred reactors or
combinations of the two. In this apparatus, the length/diameter
ratio remains predominantly within ranges of from 5:1 to 30:1,
preferably 10:1 to 20:1.
[0055] Suitable pressure conditions for the polymerization are from
1000 to 3000 bar, preferably from 1500 to 2000 bar. The reaction
temperatures are, for example, in the range from 160 to 320.degree.
C, preferably in the range from 200 to 280.degree. C.
[0056] The regulator used for controlling the molecular weight of
the copolymers is, for example, an aliphatic aldehyde or an
aliphatic ketone of the general formula I ##STR2## or mixtures
thereof.
[0057] In the formula, the R.sup.a and R.sup.b radicals are the
same or different and are selected from [0058] hydrogen; [0059]
C.sub.1-C.sub.6-alkyl, such as methyl, ethyl, n-propyl, isopropyl,
n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl,
sec-pentyl, neopentyl, 1,2-dimethylpropyl, isoamyl, n-hexyl,
isohexyl, sec-hexyl; more preferably C.sub.1-C.sub.4-alkyl, such as
methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl
and tert-butyl; [0060] C.sub.3-C.sub.12-cycloalkyl, such as
cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl,
cyclooctyl, cyclononyl, cyclodecyl, cycloundecyl and cyclododecyl;
preference is given to cyclopentyl, cyclohexyl and cycloheptyl.
[0061] The R.sup.a and R.sup.b radicals may also be covalently
bonded to one another to form a 4- to 13-membered ring. For
example, Ra and Rb together may form the following alkylene groups:
[0062] --(CH.sub.2).sub.4--, --(CH.sub.2).sub.5--,
--(CH.sub.2).sub.6--, --(CH.sub.2).sub.7--,
--CH(CH.sub.3)--CH.sub.2--CH.sub.2--CH(CH.sub.3)-- or
--CH(CH.sub.3)--CH.sub.2--CH.sub.2--CH.sub.2--CH(CH.sub.3)--.
[0063] Very particular preference is given to the use of
propionaldehyde or ethyl methyl ketone as a regulator.
[0064] Further very suitable regulators are unbranched aliphatic
hydrocarbons, for example propane, or branched aliphatic
hydrocarbons having tertiary hydrogen atoms, for example isobutane,
isopentane, isooctane or isododecane
(2,2,4,6,6-pentamethylheptane). Further additional regulators which
can be used are higher olefins, for example propylene.
[0065] Preference is likewise given to mixtures of the above
regulators with hydrogen or hydrogen alone.
[0066] The amount of regulator used corresponds to the amounts
customary for the high-pressure polymerization process.
[0067] Useful initiators for the free-radical polymerization are
the customary free-radical initiators, for example organic
peroxides, oxygen or azo compounds. Also suitable are mixtures of a
plurality of free-radical initiators. Useful free-radical
initiators include, for example, one or more peroxides selected
from the following commercially obtainable substances: [0068]
didecanoyl peroxide,
2,5-dimethyl-2,5-di(2-ethylhexanoylperoxy)hexane, tert-amyl
peroxy-2-ethylhexanoate, dibenzoyl peroxide, tert-butyl
peroxy-2-ethylhexanoate, tert-butyl peroxydiethyl acetate,
tert-butyl peroxydiethyl isobutyrate,
1,4-di(tert-butylperoxycarbo)cyclohexane as an isomer mixture,
tert-butyl perisononanoate,
1,1-di(tert-butylperoxy)-3,3,5-trimethylcyclo-hexane,
1,1-di(tert-butylperoxy)cyclohexane, methyl isobutyl ketone
peroxide, tert-butyl peroxyisopropyl carbonate,
2,2-di-tert-butylperoxy)butane or tert-butyl peroxyacetate; [0069]
tert-butyl peroxybenzoate, di-tert-amyl peroxide, dicumyl peroxide,
the isomeric di(tert-butylperoxyisopropyl)benzenes,
2,5-dimethyl-2,5-d i-tert-butylperoxyhexane, tert-butyl cumyl
peroxide, 2,5-dimethyl-2,5-di(tert-butylperoxy)hex-3-yne,
di-tert-butyl peroxide, 1,3-diisopropyl monohydroperoxide, cumene
hydroperoxide or tert-butyl hydroperoxide; or [0070] dimeric or
trimeric ketone peroxides, as disclosed, for example, by EP-A-0 813
550.
[0071] Particularly suitable peroxides are di-tert-butyl peroxide,
tert-butyl peroxypivalate, tert-butyl peroxyisononanoate or
dibenzoyl peroxide or mixtures thereof. An example of an azo
compound is azobisisobutyronitrile (AIBN). The free-radical
initiators are used in amounts customary for polymerizations.
[0072] In a preferred method, the inventive polymers are prepared
in such a way that a mixture of the monomers M1, M2 and M3 is
passed in the presence of the regulator at a temperature within the
range from about 20 to 50.degree. C., for example of 30.degree. C.,
preferably continuously, through a stirred autoclave which is
maintained at a pressure in the range from about 1500 to 2000 bar,
for example of about 1700 bar. The preferably continuous addition
of initiator which is generally dissolved in a suitable solvent,
for example isododecane, keeps the temperature in the reactor at
the desired reaction temperature, for example at from 200 to
250.degree. C. The polymer obtained after the decompression of the
reaction mixture is then isolated in a customary manner.
[0073] Modifications to this method are of course possible and can
be undertaken by those skilled in the art without unreasonable
effort. For example, the comonomers and the regulator can be
separately metered into the reaction mixture, or the reaction
temperature can be varied during the process, to name only a few
examples.
c) Fuel Oil Compositions
[0074] According to the invention, fuel oil compositions are
preferably fuels. Suitable fuels are gasoline fuels and middle
distillates, such as diesel fuels, heating oil or kerosene, and
particular preference is given to diesel fuel and heating oil.
[0075] The heating oils are, for example, low-sulfur or high-sulfur
crude oil raffinates or bituminous or brown coal distillates which
typically have a boiling range of from 150 to 400.degree. C. The
heating oils are preferably low-sulfur heating oils, for example
those having a sulfur content of at most 0.1% by weight, preferably
of at most 0.05% by weight, more preferably of at most 0.005% by
weight and in particular of at most 0.001% by weight. Examples of
heating oil are in particular heating oil for domestic oil-fired
central heating or EL heating oil. The quality requirements for
such heating oils are laid down, for example, in DIN 51-603-1 (see
also Ullmann's Encyclopedia of Industrial Chemistry, 5th Edition,
Vol. A12, p. 617 ff., which is explicitly incorporated herein by
way of reference).
[0076] The diesel fuels are, for example, crude oil raffinates
which typically have a boiling range of from 100 to 400.degree. C.
These are usually distillates having a 95% point of up to
360.degree. C. or even higher. However, they may also be "ultra low
sulfur diesel" or "City diesel", characterized by a maximum 95%
point of, for example, 345.degree. C. and a maximum sulfur content
of 0.005% by weight, or by a 95% point of, for example, 285.degree.
C. and a maximum sulfur content of 0.001% by weight. Also suitable
in addition to the diesel fuels obtainable by refining are those
obtainable by coal gasification or gas liquefaction (gas-to-liquid
(GTL) fuels). Also suitable are renewable fuels, such as biodiesel
or bioethanol, mixtures thereof or mixtures of the renewable fuels
with the aforementioned diesel fuels.
[0077] Particular preference is given to using the inventive
additive for additizing diesel fuels having a low sulfur content,
i.e. having a sulfur content of less than 0.05% by weight,
preferably of less than 0.02% by weight, in particular of less than
0.005% by weight and especially of less than 0.001% by weight, of
sulfur, or for additizing heating oil having a low sulfur content,
for example having a sulfur content of at most 0.1% by weight,
preferably of at most 0.05% by weight, for example at most 0.005%
by weight or, for example, at most 0.001% by weight.
[0078] Preference is given to using the additive according to the
invention in a proportion, based on the total amount of the fuel
oil composition, which in itself has an essentially adequate
influence on the cold flow properties of the fuel oil compositions.
Particular preference is given to using the additive in an amount
of from 0.001 to 1% by weight, more preferably from 0.01 to 0.15%
by weight, in particular from 0.01 to 0.1% by weight, based on the
total amount of the fuel oil composition.
d) Coadditives
[0079] The inventive polymers can be added to the fuel oil
compositions individually or as a mixture of such polymers and
optionally in combination with other additives known per se.
[0080] Suitable additives which can be present in fuel oils
according to the invention in addition to the inventive polymer,
especially for diesel fuels and heating oils, include detergents,
corrosion inhibitors, dehazers, demulsifiers, antifoams,
antioxidants, metal deactivators, multifunctional stabilizers,
cetane number improvers, combustion improvers, dyes, markers,
solubilizers, antistats, lubricity improvers, and also further
additives which improve the cold flow properties of the fuel, such
as nucleators, further conventional flow improvers (MDFIs),
paraffin dispersants (WASAs) and the combination of the last two
additives mentioned (WAFIs) (see also Ullmann's Encyclopedia of
Industrial Chemistry, 5th Edition, Vol. A16, p. 719 ff; or the
patents on cold flow improvers cited at the outset).
[0081] Further conventional cold flow improvers are in particular:
[0082] (a)copolymers of ethylene with at least one further
ethylenically unsaturated monomer which are different from the
polymers used in accordance with the invention; [0083] (b) comb
polymers; [0084] (c) polyoxyalkylenes; [0085] (d) polar nitrogen
compounds; [0086] (e) sulfo carboxylic acids or sulfonic acids or
their derivatives; and [0087] (f) poly(meth)acrylic esters.
[0088] In the copolymers of ethylene with at least one further
ethylenically unsaturated monomer (a), the monomer is preferably
selected from alkenylcarboxylic esters, (meth)acrylic esters and
olefins.
[0089] Suitable olefins are, for example, those having from 3 to 10
carbon atoms and having from 1 to 3, preferably having 1 or 2, in
particular having one, carbon-carbon double bond. In the latter
case, the carbon-carbon double bond may either be terminal
(.alpha.-olefins) or internal. However, preference is given to
.alpha.-olefins, particular preference to .alpha.-olefins having
from 3 to 6 carbon atoms, such as propene, 1-butene, 1-pentene and
1-hexene.
[0090] Suitable (meth)acrylic esters are, for example, esters of
(meth)acrylic acid with C.sub.1-C.sub.10-alkanols, in particular
with methanol, ethanol, propanol, isopropanol, n-butanol,
sec-butanol, isobutanol, tert-butanol, pentanol, hexanol, heptanol,
octanol, 2-ethylhexanol, nonanol and decanol.
[0091] Suitable alkenylcarboxylic esters are, for example, the
vinyl and propenyl esters of carboxylic acids having from 2 to 20
carbon atoms whose hydrocarbon radical may be linear or branched.
Among these, preference is given to the vinyl esters. Among the
carboxylic acids having branched hydrocarbon radicals, preference
is given to those whose branch is disposed in the .alpha.-position
to the carboxyl group, and particular preference is given to the
.alpha.-carbon atom being tertiary, i.e. the carboxylic acid being
a neocarboxylic acid. However, preference is given to the
hydrocarbon radical of the carboxylic acid being linear.
[0092] Examples of suitable alkenylcarboxylic esters are vinyl
acetate, vinyl propionate, vinyl butyrate, vinyl 2-ethylhexanoate,
vinyl neopentanoate, vinyl hexanoate, vinyl neononanoate, vinyl
neodecanoate and the corresponding propenyl esters, although
preference is given to the vinyl esters. A particularly preferred
alkenylcarboxylic ester is vinyl acetate.
[0093] Particular preference is given to the ethylenically
unsaturated monomer being selected from alkenylcarboxylic
esters.
[0094] Also suitable are copolymers which contain two or more
different copolymerized alkenylcarboxylic esters which differ in
the alkenyl function and/or in the carboxylic acid group. Likewise
suitable are copolymers which, in addition to the alkenylcarboxylic
ester(s), contain at least one copolymerized olefin and/or at least
one copolymerized (meth)acrylic ester.
[0095] The ethylenically unsaturated monomer is copolymerized in
the copolymer in an amount of preferably from 1 to 50 mol %, more
preferably from 10 to 50 mol % and in particular from 5 to 20 mol
%, based on the overall copolymer.
[0096] The copolymer (a) preferably has a number-average molecular
weight M.sub.n of from 1000 to 20 000, more preferably from 1000 to
10 000 and in particular from 1000 to 6000.
[0097] Comb polymers (b) are, for example, those described in
"Comb-Like Polymers, Structure and Properties", N. A. Plate and V.
P. Shibaev, J. Poly. Sci. Macromolecular Revs. 8, pages 117 to 253
(1974). Among those described there, suitable comb polymers are,
for example, those of the formula II ##STR3## where [0098] D is
R.sup.17, COOR.sup.17, OCOR.sup.17, R.sup.18, OCOR.sup.18 or
OR.sup.17, [0099] E is H, CH.sub.3, D or R.sup.18, [0100] G is H or
D, [0101] J is H, R.sup.18, R.sup.18COOR.sup.17, aryl or
heterocyclyl, [0102] K is H, COOR.sup.18, OCOR.sup.18, OR.sup.18 or
COOH, [0103] L is H, R.sup.18, COOR.sup.18, OCOR.sup.18, COOH or
aryl, where [0104] R.sup.17 is a hydrocarbon radical having at
least 10 carbon atoms, preferably having from 10 to 30 carbon
atoms, [0105] R.sup.18 is a hydrocarbon radical having at least one
carbon atom, preferably having from 1 to 30 carbon atoms, [0106] m
is a molar fraction in the range from 1.0 to 0.4 and [0107] n is a
molar fraction in the range from 0 to 0.6.
[0108] Preferred comb polymers are, for example, obtainable by
copolymerization of maleic anhydride or fumaric acid with another
ethylenically unsaturated monomer, for example with an
.alpha.-olefin or an unsaturated ester, such as vinyl acetate, and
subsequent esterification of the anhydride or acid function with an
alcohol having at least 10 carbon atoms. Further preferred comb
polymers are copolymers of .alpha.-olefins and esterified
comonomers, for example esterified copolymers of styrene and maleic
anhydride or esterified copolymers of styrene and fumaric acid.
Also suitable are mixtures of comb polymers. Comb polymers may also
be polyfumarates or polymaleates. Homo- and copolymers of vinyl
ethers are also suitable comb polymers.
[0109] Suitable polyoxyalkylenes (c) are, for example,
polyoxyalkylene esters, ethers, ester/ethers and mixtures thereof.
The polyoxyalkylene compounds preferably contain at least one, more
preferably at least two, linear alkyl groups(s) having from 10 to
30 carbon atoms and a polyoxyalkylene group having a molecular
weight of up to 5000. The alkyl group of the polyoxyalkylene
radical preferably contains from 1 to 4 carbon atoms. Such
polyoxyalkylene compounds are described, for example, in EP-A-0 061
895 and also in U.S. Pat. No. 4,491,455, which are fully
incorporated herein by way of reference. Preferred polyoxyalkylene
esters, ethers and ester/ethers have the general formula III
R.sup.19[O--(CH.sub.2).sub.y].sub.xO--R.sup.20 where [0110]
R.sup.19 and R.sup.20 are each independently R.sup.21,
R.sup.21--CO--, R.sup.21--O--CO(CH.sub.2).sub.z-- or
R.sup.21--O--CO(CH.sub.2).sub.z--CO-- [0111] where R.sup.21 is
linear C.sub.1-C.sub.30-alkyl, [0112] y is a number from 1 to 4,
[0113] x is a number from 2 to 200, and [0114] z is a number from 1
to 4.
[0115] Preferred polyoxyalkylene compounds of the formula III in
which both R.sup.19 and R.sup.20 are R.sup.21 are polyethylene
glycols and polypropylene glycols having a number-average molecular
weight of from 100 to 5000. Preferred polyoxyalkylenes of the
formula III in which one of the R19 radicals is R.sup.21 and the
other is R.sup.21--CO-- are polyoxyalkylene esters of fatty acids
having from 10 to 30 carbon atoms, such as stearic acid or behenic
acid. Preferred polyoxyalkylene compounds in which both R.sup.19
and R.sup.20 are an R.sup.21--CO-- radical are diesters of fatty
acids having from 10 to 30 carbon atoms, preferably of stearic acid
or behenic acid.
[0116] The polar nitrogen compounds (d) which are advantageously
oil-soluble may be either ionic or nonionic and preferably have at
least one, more preferably at least 2, substituent(s) of the
formula >NR.sup.22 where R.sup.22 is a
C.sub.8-C.sub.40-hydrocarbon radical. The nitrogen substituents may
also be quaternized, i.e. be in cationic form. An example of such
nitrogen compounds is that of ammonium salts and/or amides which
are obtainable by the reaction of at least one amine substituted
with at least one hydrocarbon radical with a carboxylic acid having
from 1 to 4 carboxyl groups or with a suitable derivative thereof.
The amines preferably contain at least one linear
C.sub.8-C.sub.40-alkyl radical. Suitable primary amines are, for
example, octylamine, nonylamine, decylamine, undecylamine,
dodecylamine, tetradecylamine and the higher linear homologs.
Suitable secondary amines are, for example, dioctadecylamine and
methylbehenylamine. Also suitable are amine mixtures, in particular
amine mixtures obtainable on the industrial scale, such as fatty
amines or hydrogenated tallamines, as described, for example, in
Ullmann's Encyclopedia of Industrial Chemistry, 6th Edition, 2000
electronic release, "Amines, aliphatic" chapter. Acids suitable for
the reaction are, for example, cyclohexane-1,2-dicarboxylic acid,
cyclohexene-1,2-dicarboxylic acid, cyclopentane-1,2-dicarboxylic
acid, naphthalenedicarboxylic acid, phthalic acid, isophthalic
acid, terephthalic acid and succinic acids substituted with
long-chain hydrocarbon radicals.
[0117] A further example of polar nitrogen compounds is that of
ring systems which bear at least two substituents of the formula
-A-NR.sup.23R.sup.24 where A is a linear or branched aliphatic
hydrocarbon group which is optionally interrupted by one or more
groups selected from O, S, NR.sup.35 and CO, and R.sup.23 and
R.sup.24 are each a C.sub.9-C.sub.40-hydrocarbon radical which is
optionally interrupted by one or more groups selected from O, S,
NR.sup.35 and CO, and/or substituted by one or more substituents
selected from OH, SH and NR.sup.35R.sup.36 where R.sup.35 is
C.sub.1-C.sub.40-alkyl which is optionally substituted by one or
more moieties selected from CO, NR.sup.35, O and S, and/or
substituted by one or more radicals selected from
NR.sup.37R.sup.38, OR.sup.37, SR.sup.37, COR.sup.37, COOR.sup.37,
CONR.sup.37R.sup.38, aryl or heterocyclyl, where R.sup.37 and
R.sup.38 are each independently selected from H or
C.sub.1-C.sub.4-alkyl; and R.sup.36 is H or R.sup.35.
[0118] A is preferably a methylene or polymethylene group having
from 2 to 20 methylene units. Examples of suitable R.sup.23 and
R.sup.24 radicals are 2-hydroxyethyl, 3-hydroxypropyl,
4-hydroxybutyl, 2-ketopropyl, ethoxyethyl and propoxypropyl. The
cyclic system may be homocyclic, heterocyclic, fused polycyclic or
nonfused polycyclic systems. The ring system is preferably carbo-
or heteroaromatic, in particular carboaromatic. Examples of such
polycyclic ring systems are fused benzoid structures such as
naphthalene, anthracene, phenanthrene and pyrene, fused nonbenzoid
structures such as azulene, indene, hydrindene and fluorene,
nonfused polycycles such as diphenyl, heterocycles such as
quinoline, indole, dihydroindole, benzofuran, coumarin,
isocoumarin, benzothiophene, carbazole, diphenylene oxide and
diphenylene sulfide, nonaromatic or partially saturated ring
systems such as decalin, and three-dimensional structures such as
.alpha.-pinene, camphene, bornylene, norbornane, norbornene,
bicyclooctane and bicyclooctene.
[0119] A further example of suitable polar nitrogen compounds is
that of condensates of long-chain primary or secondary amines with
carboxyl group-containing polymers.
[0120] The polar nitrogen compounds mentioned here are described in
WO 00/44857 and also in the references cited therein, which are
fully incorporated herein by way of reference.
[0121] Suitable polar nitrogen compounds are also described, for
example, in DE-A-198 48 621 and DE-A-196 22 052 or EP-B 398 101,
which are incorporated herein by way of reference.
[0122] Suitable sulfo carboxylic acids/sulfonic acids or their
derivatives (e) are, for example, those of the general formula IV
##STR4## where [0123] Y is
SO.sub.3.sup.-(NR.sup.25.sub.3R.sup.26).sup.+,
SO.sub.3.sup.-(NHR.sup.25.sub.2R.sup.26).sup.+,
SO.sub.3.sup.-(NH.sub.2R.sup.25R.sup.26),
SO.sub.3.sup.-(NH.sub.3R.sup.26) or SO.sub.2NR.sup.25R.sup.26,
[0124] X is Y, CONR.sup.25R.sup.27,
CO.sub.2.sup.-(NR.sup.25.sub.3R.sup.27).sup.+,
CO.sub.2.sup.-(NHR.sup.25.sub.2R.sup.27).sup.+,
R.sup.28--COOR.sup.27, NR.sup.25COR.sup.27, R.sup.28OR.sup.27,
R.sup.28OCOR.sup.27, R.sup.28R.sup.27, N(COR.sup.25)R.sup.27 or
Z.sup.-(NR.sup.25.sub.3R.sup.27), [0125] where [0126] R.sup.25 is a
hydrocarbon radical, [0127] R.sup.26 and R.sup.27 are each alkyl,
alkoxyalkyl or polyalkoxyalkyl having at least 10 carbon atoms in
the main chain, [0128] R.sup.28 is C.sub.2-C.sub.5-alkylene, [0129]
Z.sup.- is one anion equivalent and A and B are each alkyl, alkenyl
or two substituted hydrocarbon radicals or, together with the
carbon atoms to which they are bonded, form an aromatic or
cycloaliphatic ring system.
[0130] Such sulfo carboxylic acids and sulfonic acids and their
derivatives are described in EP-A-0 261 957, which is fully
incorporated herein by way of reference.
[0131] Suitable poly(meth)acrylic esters (f) are either homo- or
copolymers of acrylic and methacrylic esters. Preference is given
to acrylic ester homopolymers which derive from
C.sub.1-C.sub.40-alcohols. Preference is given to copolymers of at
least two different (meth)acrylic esters which differ in the
esterified alcohol. Optionally, the copolymer contains another
different copolymerized olefinically unsaturated monomer. The
weight-average molecular weight of the polymer is preferably from
50 000 to 500 000. A particularly preferred polymer is a copolymer
of methacrylic acid and methacrylic esters of saturated C.sub.14-
and C.sub.15-alcohols, in which the acid groups have been
neutralized with hydrogenated tallamine. Suitable poly(meth)acrylic
esters are described, for example, in WO 00/44857, which is fully
incorporated herein by way of reference.
e) Additive Packages
[0132] The present application finally provides an additive
concentrate comprising an inventive polymer as defined above and at
least one diluent, and also optionally at least one further
additive, in particular selected from the above coadditives.
[0133] Suitable diluents are, for example, the fractions resulting
from crude oil processing, such as kerosene, naphtha or
brightstock. Also suitable are aromatic and aliphatic hydrocarbons
and alkoxy alkanols. Diluents used with preference in the case of
middle distillates, in particular in the case of diesel fuels and
heating oils, are naphtha, kerosene, diesel fuels, aromatic
hydrocarbons, such as Solvent Naphtha heavy, Solvesso.RTM. or
Shellsol.RTM. and also mixtures of these solvents and diluents.
[0134] The inventive copolymer is present in the concentrates
preferably in an amount of from 0.1 to 80% by weight, more
preferably from 1 to 70% by weight and in particular from 20 to 60%
by weight, based on the total weight of the concentrate.
[0135] The invention will now be illustrated in detail with
reference to the nonlimiting examples which follow.
EXPERIMENTAL SECTION
Preparative Examples 1 to 23
[0136] A total of 23 different inventive polymers were prepared by
high-pressure polymerization of ethylene, 2-ethylhexyl acrylate
(EHA) and vinyl acetate (VAC).
[0137] Table 1 compares the properties of the polymers used in the
test examples which follow.
[0138] The content of ethylene, EHA and VAC in the resulting
polymers was determined by NMR spectroscopy. The viscosities were
determined to Ubbelohde DIN 51562. TABLE-US-00001 TABLE 1 Polymer E
VAC EHA Viscosity No. [Mol %] [Mol %] [Mol %] [mm.sup.2/s] M.sub.n
M.sub.w M.sub.w/M.sub.n 1 88.0 4.2 7.8 60 2088 4189 2.01 2 88.0 4.4
7.6 150 2959 6666 2.25 3 88.1 4.4 7.5 605 4635 12811 2.76 4 86.6
3.9 9.5 60 2124 4285 2.02 5 86.4 4.3 9.3 150 3022 6754 2.23 6 86.4
4.1 9.5 595 4797 13238 2.76 7 83.8 4.1 12.1 60 2064 4280 2.07 8
83.2 4.4 12.4 150 2994 7203 2.41 9 83.1 4.4 12.5 600 4744 14503
3.06 10 80.2 4.5 15.3 150 3038 7279 2.40 11 80.4 4.1 15.5 600 4681
15697 3.35 12 89.6 8.0 2.4 60 1977 3910 1.98 13 89.8 7.9 2.3 150
2831 6212 2.19 14 89.2 8.2 2.6 605 3862 11098 2.87 15 89.8 8.4 4.8
60 1928 3902 2.02 16 86.5 8.4 5.1 150 2926 6337 2.17 17 86.3 8.5
5.2 620 4613 12019 2.61 18 84.2 8.1 7.7 60 2003 4025 2.01 19 83.1
8.7 8.2 150 2855 6382 2.24 20 84.3 8.0 7.7 615 4858 13061 2.69 21
81.1 7.9 11.0 60 2100 4276 2.04 22 80.8 8.0 11.2 150 2878 6634 2.31
23 81.1 7.6 11.3 630 4774 14263 2.99 E: ethylene EHA: 2-ethylhexyl
acrylate VAC: vinyl acetate
b) Test Examples 1 to 4
[0139] The polymers 1 to 23 prepared above were used to carry out
the experiments which follow. For comparative purposes, the
following conventional MDFIs were also tested: [0140] Comparative
product A: ethylene-vinyl acetate-based polymer mixture; polymer
content 60% (Keroflux 6100, BASF AG) [0141] Comparative product B:
ethylene-vinyl acetate-based polymer; polymer content 50% (Keroflux
6103, BASF AG) [0142] Comparative product C: ethylene terpolymer;
polymer content 75% [0143] Comparative product D: ethylene-vinyl
acetate-based polymer mixture; 60% polymer content
[0144] Conventional middle distillate fuels with the above
inventive or conventional cold flow improvers were additized in
different dosages and the lower mixing temperature, the CP value
(cloud point), the PP value (pour point) and the viscosity of the
additives, and also the CFPP value (cold filter plugging point) of
the additized fuels were determined. The lower mixing temperature
was determined to QSM FKL 103; section 5.4.2 (ARAL Research), the
CP value to ASTM D 2500, the PP value of the additives to ISO 3016,
the viscosity of the additives to DIN 51512 and the CFPP value to
DIN EN 116.
Test Example 1
Lower Mixing Temperature
[0145] The lower mixing temperature in the middle distillate was
investigated by using 50% solutions of the polymers used in
accordance with the invention in Solvent Naphtha heavy. The lower
mixing temperature is of importance especially for those refineries
which mix the additives unheated into fuel oils or mix additives
into unheated fuel oils. When the lower mixing temperature of the
additive is high, the unheated mixing may lead to filter
problems.
[0146] Middle distillate used: diesel fuel, CP=-5.degree. C.,
CFPP=-9.degree. C., 25% n-paraffins, 90-20=70.degree.C.
[0147] Dosage of the additives: 500 ppm TABLE-US-00002 TABLE 2
Additive Lower mixing temperature [.degree. C.] no additive <10
Polymer No. 1 10 Polymer No. 4 10 Polymer No. 7 10 Polymer No. 8 10
Polymer No. 12 10 Polymer No. 13 10 Polymer No. 15 10 Polymer No.
16 10 Comparative product A 20 Comparative product C 15 Comparative
product D 35
[0148] As the above results show, the polymers used in accordance
with the invention in the 50% solution exhibit a distinctly lower
mixing temperature than the solution of the conventional
additives.
Test Example 2
Pour Point (PP) of the Additives
[0149] The PP of the additives was determined to ISO 3016, by using
50% solutions of the polymers in Solvent Naphtha heavy. The pour
point of the additives plays an important role for the handling
when they are mixed into the fuel oil. A very low PP enables the
convenient handling of the additives even in the case of mixing at
low temperatures and saves heating costs for additive tanks.
TABLE-US-00003 TABLE 3 Additive PP [.degree. C.] Polymer No. 2 6
Polymer No. 4 12 Polymer No. 7 -36 Polymer No. 9 -6 Polymer No. 16
-6 Polymer No. 17 18 Polymer No. 19 -18 Polymer No. 20 6
Comparative product A 21
[0150] As the above results show, the inventive additives in the
50% solution have a distinctly lower pour point than the solution
of the conventional additive.
Test Example 3
Viscosity
[0151] The viscosity was determined at 50.degree. C. to DIN 51512,
by using 50% solutions of the polymers used in accordance with the
invention in Solvent Naphtha. The viscosity of the additives is
also important for their handling when they are mixed in at low
temperatures. TABLE-US-00004 TABLE 4 Additive .eta. [mm.sup.2/s]
Polymer No. 2 40 Polymer No. 7 18 Polymer No. 12 27 Polymer No. 13
52 Polymer No. 16 40 Polymer No. 19 35 Comparative product A 55
[0152] As the above results show, the additives used in accordance
with the invention in the 50% solution have a distinctly lower
viscosity than the solution of the conventional additive.
Test Example 4
Improvement in the Cold Flow Properties of Middle Distillates
Example a
[0153] Middle distillate used: LGO, The Netherlands, CP=1.7.degree.
C., CFPP=-1.degree. C., 25% n-paraffins, 90-20=70.degree. C.
[0154] Dosage of the additives: 1500 ppm TABLE-US-00005 TABLE 5
Additive CFPP [.degree. C.] Polymer No. 2 -15 Polymer No. 3 -15
Polymer No. 6 -15 Polymer No. 13 -14 Polymer No. 16 -13 Polymer No.
17 -16 Comparative product A -7 Comparative product B -10
Comparative product C -6 Comparative product D -10
Example b
[0155] Middle distillate used: diesel, Belgium, CP=-17.degree. C.,
CFPP=-19.degree. C., 19% n-paraffins, 90-20=89.degree. C.
[0156] Dosage of the additives: 300 ppm TABLE-US-00006 TABLE 6
Additive CFPP [.degree. C.] Polymer No. 5 -25 Polymer No. 16 -25
Comparative product A -23 Comparative product B -23 Comparative
product C -24 Comparative product D -23
Example c
[0157] Middle distillate used: diesel fuel, Japan, CP=-3.6.degree.
C., CFPP=-5.degree. C., 21% n-paraffins, 90-20=90.degree. C.
[0158] Dosage of the additives: 1500 ppm TABLE-US-00007 TABLE 7
Additive CFPP [.degree. C.] Polymer No. 6 -14 Polymer No. 16 -16
Comparative product A -8 Comparative product B -6 Comparative
product C -11 Comparative product D -14
Example d
[0159] Middle distillate used: diesel fuel, Germany,
CP=-3.3.degree. C., CFPP=-5.degree. C., 18% n-paraffins,
90-20=101.degree. C.
[0160] Dosage of the additives: 150 ppm TABLE-US-00008 TABLE 8
Additive CFPP [.degree. C.] Polymer No. 3 -20 Polymer No. 12 -20
Polymer No. 13 -20 Polymer No. 14 -21 Polymer No. 17 -20
Comparative product A -16 Comparative product B -18 Comparative
product C -18 Comparative product D -18
Example e
[0161] Middle distillate used: LHO, Belgium, CP=0.degree. C.,
CFPP=-1.degree. C., 18% n-paraffins, 90-20=125.degree. C.
[0162] Dosage of the additives: 350 ppm TABLE-US-00009 TABLE 9
Additive CFPP [.degree. C.] Polymer No. 2 -19 Polymer No. 3 -19
Polymer No. 6 -19 Polymer No. 16 -16 Polymer No. 17 -17 Polymer No.
20 -18 Comparative product A -13 Comparative product B -13
Comparative product C -15 Comparative product D -13
Example f
[0163] Middle distillate used: diesel, The Netherlands,
CP=-5.degree. C., CFPP=-9.degree. C.
[0164] Dosage of the additives: 400 ppm TABLE-US-00010 TABLE 10
Additive CFPP [.degree. C.] Polymer No. 16 -21 Polymer No. 20 -21
Comparative product A -18 Comparative product B -18 Comparative
product C -19 Comparative product D -19
Example g
[0165] Middle distillate used: diesel, Poland, CP=-12.degree. C.,
CFPP=-13.degree. C., 12% n-paraffins, 90-20=73.degree. C.
[0166] Dosage of the additives: 600 ppm TABLE-US-00011 TABLE 11
Additive CFPP [.degree. C.] Polymer No. 2 -23 Polymer No. 15 -22
Polymer No. 16 -24 Comparative product A -18 Comparative product B
-17 Comparative product C -21 Comparative product D -20
[0167] The test results compiled in Tables 5 to 11 demonstrate a
surprisingly good performance of the polymers used in accordance
with the invention as cold flow improvers in middle distillate fuel
compositions. The inventive additives thus make it possible firstly
to set CFPP values comparable to those with conventional MDFIs, but
at lower dosage, or improved CFPP values at the same dosage.
[0168] As test examples 1 to 3 show, the polymers used in
accordance with the invention also enable better and more
convenient handling, since they can be mixed in at low temperatures
and also have a lower viscosity and a lower pour point than
conventional additives, so that they do not have to be warmed up,
or have to be warmed up to a lesser extent, before they are mixed
into the fuel oils.
* * * * *