U.S. patent application number 17/272049 was filed with the patent office on 2021-11-11 for use of specific copolymers for improving the cold properties of fuels or combustibles.
This patent application is currently assigned to Total Marketing Services. The applicant listed for this patent is Total Marketing Services. Invention is credited to Ana Maria CENACCHI-PEREIRA, Julie PREVOST.
Application Number | 20210348073 17/272049 |
Document ID | / |
Family ID | 1000005780060 |
Filed Date | 2021-11-11 |
United States Patent
Application |
20210348073 |
Kind Code |
A1 |
CENACCHI-PEREIRA; Ana Maria ;
et al. |
November 11, 2021 |
USE OF SPECIFIC COPOLYMERS FOR IMPROVING THE COLD PROPERTIES OF
FUELS OR COMBUSTIBLES
Abstract
The subject matter of the present invention is the use, for
improving the cold-resistance properties of a fuel or combustible
composition, of one or more copolymers comprising:--at least one
unit of formula (I): in which R.sub.1 is a hydrogen atom or a
methyl group; X is --O--CO--, or --CO--O-- or --NH--OO-- or
--CO--NH--; R.sub.2 is a C.sub.6 to C.sub.24 alkyl group; and at
least one unit of formula (II): in which R is a substituted or
unsubstituted imidazole ring. The invention also relates to
compositions of additives containing such a polymer, and also fuel
or combustible compositions to which such polymers have been added,
preferably in combination with a cold flow improver (CFI) additive
or a paraffin anti-settling additive (WASA). ##STR00001##
Inventors: |
CENACCHI-PEREIRA; Ana Maria;
(Saint Genis Laval, FR) ; PREVOST; Julie; (Lyon,
FR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Total Marketing Services |
Puteaux |
|
FR |
|
|
Assignee: |
Total Marketing Services
Puteaux
FR
|
Family ID: |
1000005780060 |
Appl. No.: |
17/272049 |
Filed: |
August 23, 2019 |
PCT Filed: |
August 23, 2019 |
PCT NO: |
PCT/EP2019/072598 |
371 Date: |
February 26, 2021 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C10L 1/146 20130101;
C10L 2200/0446 20130101; C10L 2200/0476 20130101; C10L 10/16
20130101 |
International
Class: |
C10L 1/14 20060101
C10L001/14; C10L 10/16 20060101 C10L010/16 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 28, 2018 |
FR |
1857716 |
Claims
1. A use, for improving the cold-resistance properties of a fuel or
combustible composition, of one or more copolymers comprising: at
least one unit of the following formula (I): ##STR00010## wherein
R.sub.1 is a hydrogen atom or a methyl group, X is --O--CO--, or
--CO--O-- or --NH--CO-- or --CO--NH--, and R.sub.2 is a C.sub.6 to
C.sub.24 alkyl group; and at least one unit of the following
formula (II): ##STR00011## wherein R is a substituted or
unsubstituted imidazole ring.
2. The use according to claim 1, characterised in that the group X
of formula (I) is selected from: --CO--O-- and --CO--NH--, it being
understood that the group X is linked to the vinyl carbon by the
carbon atom, and preferably the group X of formula (I) is the group
--CO--O--.
3. The use according to claim 1, characterised in that the group R2
of formula (I) is a linear or branched C.sub.8 to C.sub.24,
preferably C.sub.8 to C.sub.14 or C.sub.16 to C.sub.22, more
preferentially C.sub.12 to C.sub.14 or C.sub.18 to C.sub.22 and
more preferably C.sub.18 to C.sub.22 acyclic alkyl radical.
4. The use according to claim 1, characterised in that the unit of
formula (II) is N-vinylimidazole.
5. The use according to claim 1, characterised in that said
copolymer contains from 1 to 50% in moles of units of formula (II),
preferably from 5 to 40% in moles, more preferentially from 10 to
30% in moles, and more preferably from 10 to 25% in moles.
6. The use according to claim 1, characterised in that said
copolymer contains only units of formula (I) and units of formula
(II).
7. The use according to claim 1, characterised in that said
copolymer is a random copolymer, or a block copolymer, and
preferably said copolymer is a random copolymer.
8. The use of a copolymer according to claim 1, for lowering the
cold filter plugging point measured as per the standard NF EN 116
and/or the pour point measured as per the standard ASTM D 7346,
and/or for delaying or preventing the settling of crystals, and
preferably for lowering the cold filter plugging point measured as
per the standard NF EN 116.
9. The use according to claim 1, characterised in that said
copolymer is used in combination with at least one cold flow
improver additive, preferably selected from copolymers and
terpolymers of ethylene and vinyl and/or acrylic ester(s), alone or
in a mixture.
10. An additive composition comprising a copolymer as defined in
claim 1, and one or more cold-resistance additive(s) different from
the copolymers comprising units of formula (I) and units of formula
(II), preferably selected from cold flow improver additives,
paraffin anti-settling additives and/or dispersants, and mixtures
of these additives.
11. The additive composition according to claim 10, characterised
in that it contains at least one cold flow improver additive
selected from the copolymers of ethylene and vinyl ester(s), alone
or in a mixture; preferably selected from ethylene/vinyl acetate
(EVA) copolymers, ethylene/vinyl propionate (EVP) copolymers and
terpolymers of ethylene, vinyl acetate and another vinyl ester;
more preferentially selected from ethylene/vinyl acetate (EVA)
copolymers and mixtures thereof with a terpolymer of ethylene,
vinyl acetate and another vinyl ester, such as vinyl neodecanoate
in particular.
12. The additive composition according to claim 1, characterised in
that the weight ratio between the content of the copolymer(s)
according to the invention, on one hand, and the content of
copolymer(s) of ethylene and vinyl ester(s), on the other, is
within the range from 0.01:100 to 20:100, preferably from 0.1:100
to 10:100, and more preferably from 0.5:100 to 5:100.
13. A fuel or combustible composition, comprising: (1) at least one
hydrocarbon cut derived from one or more sources selected from the
group consisting of mineral, animal, plant and synthetic sources,
and (2) at least one copolymer as defined in claim 1.
14. The composition according to claim 13, characterised in that it
contains said copolymer(s) at a content of at least 0.0001% by
weight, preferably at a content ranging from 0.0001 to 0.01% by
weight, preferably from 0.0002 to 0.005% by weight, and more
preferably from 0.0003 to 0.003% by weight, with respect to the
total weight of the composition.
15. The composition according to claim 13, characterised in that it
further comprises at least one cold flow improver additive selected
from the copolymers of ethylene and vinyl ester(s), alone or in a
mixture.
16. The composition according to claim 14, characterised in that it
further comprises at least one cold flow improver additive selected
from ethylene/vinyl acetate (EVA) copolymers, ethylene/vinyl
propionate (EVP) copolymers and terpolymers of ethylene, vinyl
acetate and another vinyl ester; more preferentially selected from
ethylene/vinyl acetate (EVA) copolymers and mixtures thereof with a
terpolymer of ethylene, vinyl acetate and another vinyl ester, such
as vinyl neodecanoate in particular.
Description
[0001] The present invention relates to the use of specific
copolymers for improving the cold-resistance properties of fuels or
combustibles during the storage thereof and/or the use thereof at
low temperatures.
[0002] The present invention also relates to additive compositions
(or "additive packages") containing these copolymers, as well as
fuel and combustible compositions to which such copolymers have
been added, preferably in combination with a cold flow improver
additive (CFI) and/or at least one paraffin anti-settling additive
(WASA).
PRIOR ART
[0003] Fuels or combustibles containing paraffin compounds,
particularly compounds containing n-alkyl, iso-alkyl or n-alkenyl
groups such as paraffin waxes, are known to exhibit degraded flow
properties at low temperatures, typically below 0.degree. C. In
particular, it is known that the middle distillates obtained by
distillation from crude oils of petroleum origin such as diesel
fuel or heating oil, contain different quantities of n-alkanes or
n-paraffins depending from the source thereof. These compounds tend
to crystallise at low temperatures, blocking ducts, pipes, pumps
and filters, for example in motor vehicle fuel circuits. In winter
or under conditions of use of fuels or combustibles at temperatures
less than 0.degree. C., the crystallisation phenomenon of these
compounds can result in the reduction of the flow properties of the
fuels or combustibles and hence give rise to problems during the
transportation, storage and/or use thereof. The cold operability of
fuels or combustibles is a very important property, particularly to
ensure the cold starting of engines. If paraffins are crystallised
at the bottom of the tank, they can be entrained on starting into
the fuel circuit and particularly clog the filters and prefilters
disposed upstream from the injection systems (pump and injectors).
Similarly, for heating oil storage, if paraffins precipitate at the
bottom of the tank, they can be entrained and obstruct the conduits
upstream from the pump and the boiler supply system (spray nozzle
and filter).
[0004] These problems are well-known in the field of fuels and
combustibles, and numerous additives or additive mixtures have been
proposed and marketed to reduce the size of paraffin crystals
and/or change the shape thereof and/or prevent them from forming.
The smallest possible crystal size is preferred as it minimises the
risks of filter blocking or clogging.
[0005] Usual flow improvement agents known as cold flow improvers
(CFI) are generally co- and ter-polymers of ethylene and vinyl
and/or acrylic ester(s), used alone or in a mixture. These cold
flow improver additives (CFI), intended to lower the cold filter
plugging point (CFPP) and the pour point (PP), inhibit crystal
growth at low temperatures by promoting dispersion of the paraffin
crystals; these are for example polymers of ethylene and vinyl
acetate and/or vinyl propionate (EVA or EVP), also commonly
referred to as CFPP additives. This type of additives, very
extensively known by one skilled in the art, is systematically
added to conventional middle distillates at refinery outlets. These
distillates containing additives are used as diesel engine fuel or
as heating fuel. Additional quantities of these additives can be
added to the fuels sold in service stations particularly to meet
so-called Extreme Cold specifications.
[0006] To improve both the CFPP and the pour point of the
distillates, it is known to add to these CFI additives, additional
additives or "boosters" having the function of acting in
combination with the CFI additives so as to increase the efficiency
thereof. The prior art describes plenty of such additive
combinations.
[0007] By way of example, mention can be made of U.S. Pat. No.
3,275,427 describing a distillation cut middle distillate between
177 and 400.degree. C. containing an additive consisting of 90 to
10% by mass of an ethylene copolymer comprising from 10 to 30% of
vinyl acetate units of weight molar mass between 1000 and 3000
gmol.sup.-1 and from 10 to 90% by mass of a lauryl polyacrylate
and/or a lauryl polymethacrylate of weight molar mass ranging from
760 to 100.000 gmol.sup.-1.
[0008] Document EP0857776 proposes using alkylphenol-aldehyde
resins obtained from the condensation of alkylphenol and aldehyde
in association with ethylene/vinyl ester copolymers or terpolymers,
for improving the fluidity of mineral oils.
[0009] Patent application WO 2008/006965 describes the use of a
combination of a homopolymer obtained from an olefinic ester of
carboxylic acid of 3 to 12 carbon atoms and a fatty alcohol
comprising a chain of more than 16 carbon atoms and optionally an
olefinic double bond and a cold flow improver additive (CFI) of EVA
or EVP type, to increase the efficiency of CFI additives by
amplifying the effect thereof on the CFPP.
[0010] Patent application WO 2016/128379 describes the use, as a
fuel or combustible cold-resistance additive, of a block copolymer
comprising:
[0011] (i) a block A consisting of a chain of structural units
derived from one or more .alpha.,.beta.-unsaturated alkyl acrylate
or methacrylate monomers,
[0012] (ii) a block B consisting of a chain of structural units
derived from one or more .alpha.,.beta.-unsaturated monomers
containing at least one aromatic ring.
[0013] This additive is particularly useful as a CFPP booster in
association with a cold flow improver additive (CFI).
[0014] Besides improving the flow of the fuel or combustible
composition, a further aim of cold-resistance additives is that of
ensuring the dispersion of the paraffin crystals, so as to delay or
prevent the settling of such crystals and prevent the formation of
a paraffin-rich layer at the bottom of storage receptacles, tanks
or containers; these paraffin-dispersing additives are known as
anti-settling additives or WASA (acronym of the term "Wax
Anti-Settling Additive").
[0015] Modified alkylphenol-aldehyde resins were described in
document FR2969620 as an anti-settling additive in combination with
a CFPP additive.
[0016] Due to the diversification of fuel and combustible sources,
there is still a need to find new additives for improving the
properties of fuels or combustibles at low temperatures also known
as cold-resistance properties, and particularly the flow properties
thereof during the storage and/or use thereof at low
temperatures.
[0017] This need is particularly important for fuels or
combustibles comprising one or more paraffin compounds, for example
compounds containing n-alkyl, iso-alkyl or n-alkenyl groups tending
to crystallise at low temperatures.
[0018] In particular, the distillates used in fuels and
combustibles are increasingly obtained from more complex refining
operations than those obtained from direct petroleum distillation,
and can be obtained particularly from cracking, hydrocracking,
catalytic cracking processes and visbreaking processes. With the
growing demand for diesel fuels, the refiner tends to introduce
less readily usable cuts into these fuels, such as the heaviest
cuts obtained from cracking and visbreaking methods which are rich
in long-chain paraffins.
[0019] Moreover, synthetic distillates derived from the
transformation of gas such as those obtained from the Fischer
Tropsch process, as well as distillates resulting from the
treatment of biomasses of plant or animal origin, such as in
particular NexBTL and distillates comprising vegetable or animal
oil esters have appeared on the market, and represent a new range
of products usable as a base for formulating fuels or heating oils.
These products also comprising long paraffin chain
hydrocarbons.
[0020] Furthermore, the arrival of new crude oils onto the market
has been observed, much richer in paraffins than those commonly
refined and wherein the cold filter plugging point of the
distillates obtained from direct distillation was improved with
difficulty by conventional filterability additives in the same way
as those cited above.
[0021] It has been observed that the cold-resistance properties of
the distillates obtained by combining old bases and these novel
sources were hardly improved by adding conventional filterability
additives, inter alia due to the strong presence of long-chain
paraffins and the complex paraffin distribution in the composition
thereof. Indeed, in these novel distillate combinations,
discontinuous paraffin distributions have been observed, in the
presence of which known filterability additives are not always
sufficiently effective.
[0022] Therefore, there is a need to adapt cold-resistance
additives to these novel types of bases for fuels and combustibles,
considered particularly difficult to treat.
[0023] The present invention applies to fuels and combustibles
containing not only conventional distillates such as those obtained
from direct crude oil distillation, but also to bases obtained from
other sources, such as those described above.
[0024] Thus, the present invention aims at proposing novel
additives and concentrates containing them which can advantageously
be used as additives for improving the cold-resistance properties,
in particular the cold flow properties of these fuels or
combustibles, during the storage and/or use thereof at low
temperatures, typically less than 0.degree. C.
[0025] The present invention furthermore aims at proposing novel
additives for fuels and combustibles and concentrates containing
such additives, acting upon the Cold Filter Plugging Point (CFPP),
the pour point (PP), and delaying and/or preventing the settling of
crystals of hydrocarbon compounds, particularly paraffins.
[0026] Finally, the invention aims at proposing a fuel or
combustible composition having improved cold-resistance properties,
in particular at temperatures less than 0.degree. C., preferably
less than -5.degree. C.
OBJECT OF THE INVENTION
[0027] The applicant has now discovered that specific copolymers,
as described hereinafter, had unexpected properties for improving
the cold resistance of fuel and combustible compositions, including
those which are particularly difficult to treat.
[0028] The present invention thus relates to the use, for improving
the cold-resistance properties of a fuel or combustible
composition, of one or more copolymers comprising
[0029] at least one unit of the following formula (I):
##STR00002##
wherein R.sub.1 is a hydrogen atom or a methyl group,
X is --O--CO--, or --CO--O-- or --NH--CO-- or --CO--NH--, and
[0030] R.sub.2 is a C.sub.6 to C.sub.24 alkyl group; and at least
one unit of the following formula (II):
##STR00003##
wherein R is a substituted or unsubstituted imidazole ring.
[0031] According to a preferred embodiment, the polymer defined
above is used as a so-called "CFPP booster" additive, i.e. in
combination with a flow improvement additive or cold flow improver
additive (or CFI) wherein it improves the performances thereof.
[0032] The invention also relates to an additive composition
comprising such a copolymer in association with at least one
cold-resistance additive different from the copolymers according to
the invention, as well as an additive concentrate containing such a
composition. The cold-resistance additive is preferably selected
from copolymers and terpolymers of ethylene and vinyl and/or
acrylic ester(s), alone or in a mixture.
[0033] The invention also relates to a fuel or combustible
composition, comprising:
[0034] (1) at least one hydrocarbon cut derived from one or more
sources selected from the group consisting of mineral (preferably
petroleum), animal, plant and synthetic sources, and
[0035] (2) at least one copolymer as defined above.
[0036] According to a preferred embodiment, said composition
further comprises at least one cold-resistance additive different
from the copolymers according to the invention defined above.
[0037] Further aims, features, aspects and advantages of the
invention will emerge even more clearly on reading the description
and the examples which follow.
[0038] Hereinafter, and unless specified otherwise, the bounds of a
range of values are included in this range, particularly in the
expressions "between" and "ranging from . . . to . . . ".
[0039] Moreover, the expressions "at least one" and "at least" used
in the present description is equivalent to the expressions "one or
more" and "greater than or equal to".
[0040] Finally, in a manner known per se, the term CN compound or
group denotes a compound or a group containing N carbon atoms in
the chemical structure thereof.
DETAILED DESCRIPTION
[0041] Copolymer:
[0042] The invention uses a copolymer, comprising at least one unit
of the following formula (I):
##STR00004##
[0043] wherein
[0044] R.sub.1 is a hydrogen atom or a methyl group,
[0045] X is --O--CO--, or --CO--O-- or --NH--CO-- or --CO--NH--,
and
[0046] R.sub.2 is a C.sub.6 to C.sub.24 alkyl radical.
[0047] The group X of formula (I) is selected from:
[0048] X.dbd.--O--CO--, it being understood that X is then linked
to the vinyl carbon by the oxygen atom;
[0049] X.dbd.--CO--O--, it being understood that X is then linked
to the vinyl carbon by the carbon atom;
[0050] X.dbd.--NH--CO--, it being understood that X is then linked
to the vinyl carbon by the nitrogen atom; and
[0051] X.dbd.--CO--NH--, it being understood that X is then linked
to the vinyl carbon by the carbon atom.
[0052] According to a first embodiment, the group X of formula (I)
is selected from: --O--CO-- and --NH--CO--, it being understood
that the group X.dbd.--O--CO-- is linked to the vinyl carbon by the
oxygen atom and that the group X.dbd.--NH--CO-- is linked to the
vinyl carbon by the nitrogen atom. In this embodiment, the group X
of formula (I) is preferably the group --O--CO--.
[0053] According to a second embodiment, the group X of formula (I)
is selected from: --CO--O-- and --CO--NH--, it being understood
that the group X is linked to the vinyl carbon by the carbon atom.
In this embodiment, the group X of formula (I) is preferably the
group --CO--O--.
[0054] According to a particularly preferred embodiment, the group
X is a group --CO--O--, X being linked to the vinyl carbon by the
carbon atom.
[0055] The group R.sub.2 of formula (I) is a C.sub.6 to C.sub.24
alkyl radical. This alkyl radical can be linear or branched, cyclic
or acyclic. This alkyl radical can comprise a linear or branched
part and a cyclic part.
[0056] According to a first embodiment, the group R.sub.2 of
formula (I) is a linear or branched C.sup.6 to C.sub.14, preferably
C.sub.8 to C.sub.14, more preferentially C.sub.12 to C.sub.14
acyclic alkyl radical.
[0057] Mention can be made for example, non-restrictively, of alkyl
groups such as octyl, decyl, dodecyl, ethyl-2-hexyl, isooctyl,
isodecyl and isododecyl, C.sub.14 alkyl groups.
[0058] According to a particularly preferred embodiment, the group
X is a group --CO--O--, X being linked to the vinyl carbon by the
carbon atom, and the group R.sub.2 is a linear or branched C.sub.8
to C.sub.14, preferably Cm to C.sub.14, and more preferentially
C.sub.12 to C.sub.14 acyclic alkyl radical.
[0059] The units according to this embodiment correspond to those
derived from monomers selected from alkyl acrylates and
methacrylates having a C.sub.8 to C.sub.14, preferably Cm to
C.sub.14, and more preferentially C.sub.12 to C.sub.14 alkyl
group.
[0060] According to a second embodiment, the group R.sub.2 of
formula (I) is a linear or branched C.sub.14 to C.sub.24,
preferably C.sub.16 to C.sub.22, more preferentially C.sub.18 to
C.sub.22 acyclic alkyl radical.
[0061] According to a particularly preferred embodiment, the group
X is a group --CO--O--, X being linked to the vinyl carbon by the
carbon atom, and the group R.sub.2 is a linear or branched C.sub.14
to C.sub.24, preferably C.sub.16 to C.sub.22, more preferentially
C.sub.18 to C.sub.22 acyclic alkyl radical.
[0062] The units according to this embodiment correspond to those
derived from monomers selected from alkyl acrylates and
methacrylates having a C.sub.14 to C.sub.24, preferably C.sub.16 to
C.sub.22, and more preferentially C.sub.18 to C.sub.22 alkyl
group.
[0063] The copolymer used in the present invention also comprises
at least one unit of the following formula (II):
##STR00005##
[0064] wherein
[0065] R is a substituted or unsubstituted imidazole ring.
[0066] The substituent(s) optionally present on the imidazole
ring(s) can be saturated or unsaturated, and be particularly
selected from hydrocarbon, oxygenated, nitrogenous, halogenated,
etc. substituents.
[0067] According to an embodiment, the units of formula (II) are
derived from one or more vinyl monomers bearing a group R as
described above.
[0068] Mention can be made by way of particularly preferred example
of 1-vinylimidazole (or N-vinylimidazole):
##STR00006##
[0069] The copolymer used in the present invention can be
optionally cross-linked. Preferably, it is not cross-linked.
[0070] The copolymer used in the present invention can be
advantageously a random copolymer, or a block copolymer. According
to a particularly preferred embodiment, it is a random
copolymer.
[0071] The copolymer according to the invention contains
advantageously from 50 to 99% in moles of units of formula (I),
preferably from 60 to 95% in moles, more preferentially from 70 to
90% in moles, and more preferably from 75 to 90% in moles.
[0072] The copolymer according to the invention contains
advantageously from 1 to 50% in moles of units of formula (II),
preferably from 5 to 40% in moles, more preferentially from 10 to
30% in moles, and more preferably from 10 to 25% in moles.
[0073] Preferably, the copolymer used in the present invention only
contains units of formula (I) and units of formula (II).
[0074] The copolymer used in the present invention can be obtained
by copolymerising:
[0075] at least one monomer complying with the following formula
(IA):
##STR00007## [0076] wherein [0077] R.sub.1, X and R.sub.2 are as
defined above, the preferred variants of R.sub.1, X and R.sub.2
according to formula (I) described above also being preferred
variants of formula (IA), and
[0078] at least one monomer complying with the following formula
(IIA):
##STR00008## [0079] wherein R is as defined above, the preferred
variants of R according to formula (II) described above also being
preferred variants of formula (IIA)
[0080] When the group X of the monomer of formula (IA) is the group
--O--CO--, it being understood that the group --O--CO-- is linked
to the vinyl carbon by the oxygen atom, the monomer of formula (IA)
is, preferably, selected from alkyl vinyl esters having a C.sub.6
to C.sub.24 alkyl group, and more preferentially from alkyl vinyl
esters having a C.sub.12 to C.sub.14 or C.sub.18 to C.sub.22 alkyl
group. The alkyl radical of the alkyl vinyl ester is linear or
branched, cyclic or acyclic, preferably acyclic.
[0081] Of the alkyl vinyl ester monomers, mention can be made by
way of non-restrictive example of vinyl octanoate, vinyl decanoate,
vinyl dodecanoate, vinyl tetradecanoate, vinyl
2-ethylhexanoate.
[0082] When the group X of the monomer of formula (IA) is the group
--CO--O--, it being understood that the group --CO--O-- is linked
to the vinyl carbon by the carbon atom, the monomer or formula (IA)
is typically selected from alkyl acrylates and methacrylates having
a C.sub.6 to C.sub.24 alkyl group, and more preferentially from
alkyl acrylates and methacrylates having a C.sub.12 to C.sub.14 or
C.sub.18 to C.sub.22 alkyl group.
[0083] Of the alkyl (meth)acrylates capable of being used as
monomers in the manufacture of the copolymer of the invention,
mention can be made of C.sub.6 to C.sub.24 alkyl acrylates and
C.sub.6 to C.sub.24 alkyl methacrylates, and particularly, by way
of non-restrictive examples: n-octyl acrylate, n-octyl
methacrylate, n-decyl acrylate, n-decyl methacrylate, n-dodecyl
acrylate, n-dodecyl methacrylate, ethyl-2-hexyl acrylate,
ethyl-2-hexyl methacrylate, isooctyl acrylate, isooctyl
methacrylate, isodecyl acrylate, isodecyl methacrylate, C.sub.12 to
C.sub.14 alkyl acrylates and C.sub.12 to C.sub.14 alkyl
methacrylates, C.sub.18 to C.sub.22 alkyl acrylates and C.sub.18 to
C.sub.22 alkyl methacrylates. Using C.sub.12 to C.sub.14 alkyl
acrylates and C.sub.12 to C.sub.14 alkyl methacrylates is
particularly preferred.
[0084] The monomers of formula (IIA) are vinyl monomers bearing a
group R as described above.
[0085] Mention can be made by way of particularly preferred monomer
of formula (IIA) of 1-vinylimidazole (or N-vinylimidazole) of
formula:
##STR00009##
[0086] It is understood that it would not be outside the scope of
the invention if the polymer according to the invention were
obtained from different monomers from those of formula (IA) and
(IIA) above, insofar as the final copolymer corresponds to a
polymer comprising units of formula (I) and units of formula (II)
as defined above. For example, it would not be outside the scope of
the invention, if the polymer were obtained by polymerising
different monomers, followed by post-functionalisation. For
example, the units of formula (I) can be obtained using acrylic
acid, by a transesterification reaction.
[0087] The polymer according to the invention can be prepared
according to any known polymerisation method. The different
polymerisation and cross-linking techniques and conditions are
described extensively in the literature and are part of the general
knowledge of a person skilled in the art.
[0088] In the case of a random copolymer, conventional radical
polymerisation can particularly be performed: the procedure
generally involves mixing the different monomers in a suitable
solvent, and the copolymerisation is initiated by means of a
radical polymerisation agent.
[0089] In the case of a block copolymer, the procedure can
particularly involve sequenced and controlled polymerisation. Such
a polymerisation is, advantageously, selected from controlled
radical polymerisation; for example, by Atom Transfer Radical
Polymerisation (ATRP); Nitroxide-mediated polymerisation (NMP);
degenerative transfer processes such as iodine transfer radical
polymerisation (ITRP) or Reversible Addition-Fragmentation Chain
Transfer (RAFT); ATRP-derived polymerisations such as
polymerisations using initiators for continuous activator
regeneration (ICAR) or using activators regenerated by electron
transfer (ARGET).
[0090] The copolymer according to the invention has,
advantageously, a weight average molar mass (Mw) between 1000 and
50,000 gmol.sup.-1, more preferentially between 1000 and 20,000,
even more preferentially between 3,000 and 15,000 gmol.sup.-1.
[0091] The copolymer according to the invention has,
advantageously, a number average molar mass (Mn) between 1000 and
50,000 gmol.sup.-1, more preferentially between 1000 and 20,000,
even more preferentially between 2,000 and 10,000 gmol.sup.-1.
[0092] The number and weight average molar masses are measured by
Size Exclusion Chromatography (SEC).
[0093] Use:
[0094] The copolymer described above is used to improve the
cold-resistance properties of a fuel or combustible composition, in
particular, of a composition selected from diesel fuels,
biodiesels, B.sub.x type fuel oils, fuel oils, preferably, heating
oils.
[0095] The fuel or combustible composition is as described
hereinafter and advantageously comprises at least one hydrocarbon
cut obtained from one or more sources selected from the group
consisting of mineral, preferably petroleum, animal, plant and
synthetic sources.
[0096] Advantageously, said copolymer is used to improve the flow
properties at low temperatures of the fuel or combustible during
the storage and/or use thereof, at low temperatures, by lowering
the cold filter plugging point (or CFPP, measured as per the
standard NF EN 116) thereof and/or the pour point (or PP, measured
as per the standard ASTM D 7346) and/or by delaying or preventing
the settling of crystals, and preferably by lowering the cold
filter plugging point (CFPP, measured as per the standard NF EN
116) thereof.
[0097] The copolymer according to the invention can be used to
delay or prevent the settling of crystals of paraffins and more
specifically of n-alkanes, preferably, n-alkanes containing at
least 12 carbon atoms, more preferentially at least 20 carbon
atoms, even more preferentially preferably at least 24.
[0098] According to a preferred embodiment, the copolymer according
to the invention is used as a CFPP booster additive, i.e. in
combination with a flow improvement additive or cold flow improver
additive (or CFI).
[0099] The cold flow improver additive (CFI) is, preferably,
selected from copolymers and terpolymers of ethylene and vinyl
and/or acrylic ester(s), alone or in a mixture.
[0100] In this embodiment, the copolymer according to the invention
is used to amplify the fluidifying effect of the cold flow improver
additive, particularly by lowering the cold filter plugging point
(CFPP) thereof and/or the pour point, and/or by delaying or
preventing the settling of crystals, such as those containing
paraffins.
[0101] This effect is usually known as a "CFPP booster" effect
insofar as the presence of the copolymer according to the invention
improves the fluidifying property of the CFI additive. This
improvement results, in particular, in a significant reduction in
the CFPP of the fuel or combustible composition to which this
association has been added compared to the same fuel or combustible
composition to which only the CFI additive has been added, at the
same treatment rate. Generally, a significant reduction in the CFPP
results in a decrease of at least 3.degree. C. of the CFPP as per
the standard NF EN 116.
[0102] According to a particularly preferred embodiment, the
copolymer is used to amplify the fluidifying (flow) effect of the
cold flow improver additive (CFI) by improving the Cold Filter
Plugging Point (CFPP) of the fuel or combustible, the CFPP being
measured as per the standard NF EN 116.
[0103] The copolymer can be added to the fuels or combustibles in
the refinery, and/or be incorporated downstream from the refinery,
optionally, in a mixture with other additives, in the form of an
additive concentrate, also known as "additive package".
[0104] The copolymer is advantageously used in the fuel or
combustible at a content of at least 0.0001% by weight, with
respect to the total weight of the fuel or combustible
composition.
[0105] Preferably, the content of said copolymer ranges from 0.0001
to 0.01% by weight, preferably from 0.0002 to 0.005% by weight, and
more preferably from 0.0003 to 0.003% by weight, with respect to
the total weight of the fuel or combustible composition.
[0106] Additive Composition:
[0107] The invention also relates to an additive composition
comprising a copolymer as described above, and one or more
cold-resistance additive(s) different from the copolymer comprising
units of formula (I) and units of formula (II) as described
above.
[0108] According to a preferred embodiment, the cold-resistance
additive(s) are selected from cold flow improver additives,
paraffin anti-settling additives and/or dispersants, and mixtures
of these additives.
[0109] The cold flow improver additives (CFI) can particularly be
selected from copolymers and terpolymers of ethylene and vinyl
and/or acrylic ester(s), alone or in a mixture. By way of example,
mention can be made of ethylene and unsaturated ester copolymers,
such as the ethylene/vinyl acetate (EVA), ethylene/vinyl propionate
(EVP), ethylene/vinyl ethanoate (EVE), ethylene/methyl methacrylate
(EMMA), and ethylene/alkyl fumarate copolymers described, for
example, in the documents U.S. Pat. Nos. 3,048,479, 3,627,838,
3,790,359, 3,961,961 and EP261957. Mention can also be made of
terpolymers or ethylene, vinyl acetate and another vinyl ester, for
example vinyl neodecanoate.
[0110] According to a preferred embodiment, the composition
contains at least one cold flow improver additive (CFI) selected
from the copolymers of ethylene and vinyl ester(s), alone or in a
mixture, in particular ethylene/vinyl acetate (EVA) copolymers,
ethylene/vinyl propionate (EVP) copolymers and terpolymers of
ethylene, vinyl acetate and another vinyl ester; more
preferentially ethylene/vinyl acetate (EVA) copolymers and mixtures
thereof with a terpolymer of ethylene, vinyl acetate and another
vinyl ester, such as in particular vinyl neodecanoate.
[0111] In this embodiment, the weight ratio between the copolymer
content according to the invention, on one hand, and the ethyl and
vinyl ester copolymer content, on the other, is advantageously
within the range from 0.01:100 to 20:100, preferably from 0.1:100
to 10:100, and more preferably from 0.5:100 to 5:100. A
particularly preferred weight ratio is 1:100.+-.10%.
[0112] The paraffin anti-settling additives and/or dispersants
(WASA) can be particularly, but not restrictively, selected from
the group consisting of (meth)acrylic acid/alkyl (meth)acrylate
copolymers amidified by a polyamine, polyamine alkenylsuccinimides,
derivatives of phthalamic acid and double-chain fatty amine;
optionally grafted alkylphenol resins. Examples of such additives
are given in the following documents: EP261959, EP593331, EP674689,
EP327423, EP512889, EP832172; US2005/0223631; U.S. Pat. No.
5,998,530; WO93/14178.
[0113] The particularly preferred paraffin anti-settling additives
and/or dispersants (WASA) are selected from alkylphenol resins and
alkylphenol resins grafted for example with functional groups such
as polyamines.
[0114] The additive composition can also comprise one or more other
additives routinely used in fuels or combustibles, different from
the copolymer according to the invention and the cold-resistance
additives described above.
[0115] The additive composition can, typically, comprise one or
more other additives selected from detergents, anti-corrosion
agents, dispersants, demulsifiers, biocides, reodorisers, cetane
number improvers, friction modifiers, lubricity additives or
oiliness additives, combustion-aid agents (catalytic combustion and
soot promoters), anti-wear agents and/or conductivity modifying
agents.
[0116] Of these additives, mention can particularly be made of:
[0117] a) cetane number improvers, particularly (but not
restrictively) selected from alkyl nitrates, preferably 2-ethyl
hexyl nitrate, aryl peroxides, preferably benzyl peroxide, and
alkyl peroxides, preferably ter-butyl peroxide;
[0118] b) anti-foaming agents, particularly (but not restrictively)
selected from polysiloxanes, oxyalkylated polysiloxanes, and fatty
acid amides obtained from vegetable or animal oils. Examples of
such additives are given in EP861882, EP663000, EP736590;
[0119] c) detergent and/or anti-corrosion additives, particularly
(but not restrictively) selected from the group consisting of
amines, succinimides, alkenylsuccinimides, polyalkylamines,
polyalkyl polyamines, polyetheramines, quaternary ammonium salts
and triazole derivatives; examples of such additives are given in
the following documents: EP0938535, US2012/0010112 and
WO2012/004300. Block copolymers formed from at least one polar unit
and one nonpolar unit can advantageously be used, such as for
example those described in the patent application FR 1761700 held
by the Applicant;
[0120] d) lubricity additives or anti-wear agents, particularly
(but not restrictively) selected from the group consisting of fatty
acids and the ester or amide derivatives thereof, particularly
glycerol monooleate, and mono- and polycyclic carboxylic acid
derivatives. Examples of such additives are given in the following
documents: EP680506, EP860494, WO98/04656, EP915944, FR2772783,
FR2772784.
[0121] The additive composition can, advantageously, comprise from
0.1 to 50% by weight of copolymer as described above, with respect
to the total weight of the additive composition.
[0122] The present invention also relates to an additive
concentrate comprising an additive composition as described above,
in a mixture with an organic liquid. The organic liquid is
advantageously inert with respect to the constituents of the
additive composition, and miscible with fuels or combustibles,
particularly those derived from one or more sources selected from
the group consisting of mineral sources, preferably petroleum,
animal, plant, and synthetic.
[0123] The organic liquid is preferably selected from aromatic
hydrocarbon solvents such as the solvent marketed under the name
"SOLVESSO", alcohols, ethers and other oxygenated compounds, and
paraffinic solvents such as hexane, pentane or isoparaffins, alone
or in a mixture.
[0124] Fuel or Combustible Composition:
[0125] The invention also relates to a fuel or combustible
composition, comprising:
[0126] (1) at least one hydrocarbon cut derived from one or more
sources selected from the group consisting of mineral, animal,
plant and synthetic sources, and
[0127] (2) at least one copolymer as defined above.
[0128] The mineral sources are preferably petroleum.
[0129] The fuel or combustible composition according to the
invention advantageously comprises said copolymer(s) at a content
of at least 0.0001% by weight, with respect to the total weight of
the fuel or combustible composition. Preferably, the copolymer
content ranges from 0.0001 to 0.01% by weight, preferably from
0.0002 to 0.005% by weight, and more preferably from 0.0003 to
0.003% by weight, with respect to the total weight of the fuel or
combustible composition.
[0130] According to a preferred embodiment, said composition
further comprises at least one cold-resistance additive, selected
from cold-flow additives (CFI) and paraffin anti-settling additives
and/or dispersants (WASA), different from the copolymers according
to the invention comprising units of formula (I) and units of
formula (II). Such additives are advantageously selected from those
described above.
[0131] In this embodiment, the composition advantageously contains
at least 20 ppm, preferably at least 50 ppm, advantageously between
20 and 5000 ppm, more preferentially between 50 and 1000 ppm in
total of cold-resistance additive(s).
[0132] The fuels or combustibles can be selected from liquid
hydrocarbon fuels or combustibles, alone or in a mixture. The
liquid hydrocarbon fuels or combustibles particularly comprise
middle distillates of boiling point between 100 and 500.degree. C.
These distillates can for example be selected from distillates
obtained by direct distillation of crude hydrocarbons, vacuum
distillates, hydrotreated distillates, distillates obtained from
catalytic cracking and/or hydrocracking of vacuum distillates,
distillates resulting from ARDS (atmospheric residue
desulphurisation) and/or visbreaking type conversion processes,
distillates obtained from Fischer Tropsch cut valorisation,
distillates resulting from the BTL (biomass to liquid) conversion
of plant and/or animal biomass, taken alone or in combination,
and/or biodiesels of animal and/or plant origin and/or vegetable
and/or animal oils and/or oil esters.
[0133] The sulphur content of the fuels or combustibles is,
preferably, less than 5000 ppm, preferably less than 500 ppm, and
more preferentially less than 50 ppm, or even less than 10 ppm, and
advantageously free from sulphur.
[0134] The fuel or combustible is, preferably, selected from diesel
fuels, biodiesels, B.sub.x type diesel fuels and fuel oils,
preferably, heating oils.
[0135] The term B.sub.x type diesel fuel for a Diesel engine
(compression engine) denotes a diesel fuel which contains x % (v/v)
of plant or animal esters (including used cooking oils) converted
by a chemical process known as transesterification reacting this
oil with an alcohol in order to obtain fatty acid esters (FAE).
With methanol and ethanol, fatty acid methyl esters (FAME) and
fatty acid ethyl esters (FAEE) are respectively obtained. The
letter "B" followed by a number x ranging from 0 to 100, which
indicates the percentage of FAE contained in the diesel fuel. Thus,
a B99 contains 99% FAE and 1% middle distillates of fossil origin,
B20, 20% FAE and 80% middle distillates of fossil origin, etc.
Therefore, a distinction is made between B.sub.0 type diesel fuels
which do not contain oxygenated compounds, B.sub.x type diesel
fuels which contain x % (v/v) vegetable or animal oil or fatty acid
esters, most often methyl esters (VOME or FAME). When the FAE is
used alone in engines, the fuel is denoted using the term B100.
[0136] The fuel or combustible can also contain hydrogenated
vegetable oils, known to a person skilled in the art as HVO
(hydrogenated vegetable oil) or HDRD (hydrogenation-derived
renewable diesel).
[0137] According to a specific development, the fuel or combustible
is selected from diesel fuels, biodiesels and Bx type diesel fuels,
hydrogenated vegetable oils (HVO), and mixtures thereof.
[0138] The fuel or combustible composition can also contain one or
more additional additives, different from the copolymers and the
cold-resistance additives described above. Such additives can be
particularly selected from detergents, anti-corrosion agents,
dispersants, demulsifiers, anti-foaming agents, biocides,
reodorisers, cetane number improvers, friction modifiers, lubricity
additives or oiliness additives, combustion-aid agents (catalytic
combustion and soot promoters), anti-wear agents and/or
conductivity modifying agents.
[0139] These additional additives can be generally present in a
quantity ranging from 50 to 1000 ppm (each).
[0140] According to a further embodiment of the invention, a method
for improving the cold-resistance properties of a fuel or
combustible composition comprises the successive steps of:
[0141] a) determining the most suitable additive composition for
the fuel or combustible composition to be treated as well as the
treatment rate required to attain a given specification relative to
the cold-resistance properties for the specific fuel or combustible
composition, said additive composition comprising at least one
copolymer according to the invention and, optionally, at least one
cold-resistance additive, selected from cold flow improver
additives and paraffin anti-settling additives and/or dispersants,
different from the copolymers comprising units of formula (I) and
units of formula (II);
[0142] b) treating the fuel or combustible composition with the
quantity determined in step a) of said additive composition.
[0143] The method for improving cold-resistance properties is
typically intended for a fuel or combustible composition as
described above.
[0144] Step a) is carried out according to any known method and is
part of the routine practice in the field of fuel or combustible
additivation. This step involves defining a representative
characteristic of the cold-resistance properties of the fuel or
combustible, for example the low-temperature flow characteristics,
setting the target value then determining the improvement which is
required to attain the specification.
[0145] For example, a specification relative to cold resistance can
be a European Extreme Cold specification defining, in particular, a
maximum CFPP as per the standard NF EN 116. The determination of
the quantity of additive composition to be added to the fuel or
combustible composition to attain the specification will be carried
out typically by comparing with the fuel or combustible composition
without said additive composition.
[0146] The quantity of copolymer required to treat the fuel or
combustible composition can vary according to the nature and origin
of the fuel or combustible, in particular according to the content
and nature of the paraffinic compounds contained therein. The
nature and origin of the fuel or combustible can therefore also be
a factor to be taken into account for step a).
[0147] The method for improving the cold-resistance properties can
also comprise an additional step after step b) of verifying the
target attained and/or adjusting the treatment rate with the
additive composition.
[0148] The examples hereinafter are given by way of illustration of
the invention, and cannot be interpreted in such a way as to
restrict the scope thereof.
EXAMPLES
Example 1: Synthesis of Various Polymers
[0149] Starting Compounds: [0150] Monomer 1: C.sub.12/C.sub.14
alkyl acrylate (A12/14) (CAS 2156-97-0 and 21643-42-5) [0151]
Monomer 2: 1-vinylimidazole (NVI) (CAS 1072-63-5) [0152] Initiator:
2,2'-Azobis-(2-methylpropionitrile) (AIBN) (CAS 78-67-1) [0153]
Transfer agent: Butanethiol (CAS 109-79-5) [0154] Control agent:
Trithiocarbonate (CAS 558484-21-2) [0155] Solvent: 1,4-Dioxane (CAS
123-91-1)
[0156] Synthesis Protocol of a C.sub.12/C.sub.14 Alkyl Acrylate and
N-Vinylimidazole Random Copolymer with a Molar Ratio 80:20:
[0157] 8.84 g (35.4 mmol) of C.sub.12/C.sub.14 alkyl acrylate,
0.832 g (8.84 mmol) of 1-vinylimidazole, 0.146 g (1.62 mmol) of
butanethiol and 15.23 g (14.7 mL) of 1,4-Dioxane are introduced
into a 25 mL round-bottom flask equipped with a nitrogen inlet and
outlet. The mixture is then stirred and degassed with a nitrogen
stream for 30 minutes. In parallel, a solution of AIBN (0.097 g;
0.57 mmol) in 1,4-Dioxane (1 mL) is also prepared and placed under
degassing for 30 minutes. The round-bottom flask containing the
reaction medium is placed under heating and once the target
temperature has been attained (70.degree. C.), the initiator
solution is introduced to start the polymerisation. The reaction is
left for 6 h at 70.degree. C. At the end of the reaction, the
heating is switched off and the medium is exposed to air to stop
the polymerisation. The solvent is then evaporated in a vacuum to
retrieve the polymer.
[0158] The random polymers of the different examples for which the
characteristics are featured in table I hereinafter were
synthesised according to this protocol. The quantity and nature of
the monomers were adapted in each case.
[0159] Synthesis Protocol of a C.sub.12/C.sub.14 Alkyl Acrylate and
N-Vinylimidazole Block Copolymer with a Molar Ratio 80:20
[0160] Synthesis of Block 1:
[0161] 8.5 g (34 mmol) of C.sub.12/C.sub.14 alkyl acrylate, 0.329 g
(0.94 mmol) of trithiocarbonate and 9.0 g of 1,4-Dioxane are
introduced into a 25 mL round-bottom flask equipped with a nitrogen
inlet and outlet. The mixture is then stirred and degassed with a
nitrogen stream for 30 minutes. In parallel, a solution of AIBN
(0.015 g; 0.094 mmol) in 1,4-Dioxane (1 mL) is also prepared and
placed under degassing for 30 minutes. The round-bottom flask
containing the reaction medium is placed under heating and once the
target temperature has been attained (70.degree. C.), the initiator
solution is introduced to start the polymerisation. The reaction is
left at 70.degree. C. until the conversion into C.sub.12/C.sub.14
alkyl acrylate is greater than 95%.
[0162] Synthesis of Block 2:
[0163] 0.795 g (8.46 mmol) of 1-vinylimidazole is introduced into
the reaction medium obtained from the synthesis of block 1, and the
mixture is stirred and degassed with a nitrogen stream for 30
minutes. In parallel, a new solution of AIBN (0.015 g; 0.094 mmol)
is prepared in 1,4-Dioxane and placed under degassing for 30
minutes. The AIBN solution is then added to the reaction medium to
restart the polymerisation. The reaction is left for 6 h at
70.degree. C. At the end of the reaction, the heating is switched
off and the medium is exposed to air to stop the polymerisation.
The solvent is then evaporated in a vacuum to retrieve the
polymer.
[0164] The block copolymers of the different examples for which the
characteristics are featured in table I hereinafter were
synthesised according to this protocol. The quantity of the
monomers was adapted in each case.
[0165] The polymers were characterised by size exclusion
chromatography (SEC), in order to determine the composition and
molar mass of each copolymer.
[0166] The characteristics of the polymers synthetised according to
the protocols described hereinabove are compiled in table I
below:
TABLE-US-00001 M.sub.W M.sub.n Type of Monomer Monomer (g (g
polymer of formula (I) of formula (II) mol.sup.-1) mol.sup.-1)
Homopolymer C.sub.12/C.sub.14 alkyl -- 7750 4920 acrylate Random
C.sub.12/C.sub.14 alkyl N-vinylimidazole 8100 5700 copolymer
acrylate 20% in moles 80% in moles Random c C.sub.12/C.sub.14 alkyl
N-vinylimidazole 10230 6220 copolymer acrylate 10% in moles 90% in
moles Random C.sub.18/C.sub.22 alkyl N-vinylimidazole 5900 3400
copolymer acrylate 20% in moles 80% in moles Block
C.sub.12/C.sub.14 alkyl N-vinylimidazole 8613 7245 copolymer
acrylate 20% in moles 80% in moles Block C.sub.12/C.sub.14 alkyl
N-vinylimidazole 9559 7586 copolymer acrylate 10% in moles 90% in
moles
Example 2: Evaluation of Cold-Resistance Performances
[0167] The polymers described in example 1 were tested as
cold-resistance additives in a particularly difficult to treat
diesel fuel type fuel composition G, and the characteristics of
which are detailed in table II below:
TABLE-US-00002 Characteristic Method Value Density at 15.degree. C.
ISO 12185 831.2 kg/m.sup.3 Viscosity at 20.degree. C. ISO 3104 5.1
mm.sup.2/s Viscosity at 40.degree. C. ISO 3104 3.5 mm.sup.2/s Cloud
point (CP) .degree. EN 23015 -3.degree. C. Cold filter plugging EN
116 -2.degree. C. point (CFPP) Pour point (PP) ASTM D 7346
-12.degree. C. Paraffin content 21.42% by weight C16+ n-paraffin
content 11.30% by weight D86 distillation point ISO 3405 Starting
point 173.0.degree. C. Point at 5% vol. 196.6.degree. C. Point at
10% vol. 215.4.degree. C. Point at 20% vol. 243.4.degree. C. Point
at 30% vol. 261.9.degree. C. Point at 40% vol. 276.0.degree. C.
Point at 50% vol. 287.7.degree. C. Point at 60% vol. 299.3.degree.
C. Point at 70% vol. 311.4.degree. C. Point at 80% vol.
325.5.degree. C. Point at 90% vol. 343.7.degree. C. Point at 95%
vol. 356.2.degree. C. End point 359.0.degree. C. Distilled volume
97.4 ml Residue 0.6 ml Losses 1.8 ml
[0168] A package containing the following two conventional
commercial cold flow improver additives (CFI additives), in
Solvesso 150 solvent, was added to the diesel fuel composition G:
[0169] 0.5% by weight of CP7956C additive marketed by the company
Total Additifs Carburants S{acute over (p)}eciaux, and which is an
ethylene/vinyl acetate (EVA) copolymer; [0170] 0.5% by weight of
Dodiflow D4134 additive marketed by the company Clariant, and which
is an ethylene/vinyl acetate/vinyl neodecanoate terpolymer.
[0171] This package was incorporated in the diesel fuel composition
G at a content of 300 ppm by weight of active substance (i.e. 150
ppm by weight of each additive) with respect to the total weight of
the diesel fuel composition.
[0172] The additive-containing diesel fuel composition G1 was thus
obtained. It has a Cold filter plugging point (CFPP, standard EN
116) of -6.degree. C.
[0173] The performances as cold-resistance additives of each of the
polymers of example 1 were tested, by evaluating their ability to
lower the cold filter plugging point (CFPP) of the
additive-containing diesel fuel composition G1.
[0174] Each polymer was added at a content of 3 ppm by weight
(0.0003% by weight) to the composition G1, to produce the diesel
fuel G2, the CFPP of which was then measured, in accordance with
the standard EN 116.
[0175] The results obtained are featured in table III below:
TABLE-US-00003 CFPP (.degree. C.) Difference in CFPP: Type of
polymer Diesel fuel G2 CFPP G1 - CFPP G2 Homopolymer -7.degree. C.
1.degree. C. C.sub.12/C.sub.14 alkyl acrylate Random copolymer
-13.degree. C. 7.degree. C. C.sub.12/C.sub.14 alkyl acrylate/
N-vinylimidazole (80/20) Random copolymer -13.degree. C. 7.degree.
C. C.sub.12/C.sub.14 alkyl acrylate/ N-vinylimidazole (90/10)
Random copolymer -15.degree. C. 9.degree. C. C.sub.18/C.sub.22
alkyl acrylate/ N-vinylimidazole (80/20) Block copolymer
-11.degree. C. 5.degree. C. C.sub.12/C.sub.14 alkyl acrylate/
N-vinylimidazole (80/20) Block copolymer -12.degree. C. 6.degree.
C. C.sub.18/C.sub.22 alkyl acrylate/ N-vinylimidazole (90/10)
[0176] The above results show that using the copolymers according
to the invention results in a significant lowering of the CFPP,
ranging from 7 to 9 points for random copolymers, and from 5 to 6
points for block copolymers.
* * * * *