Note: Descriptions are shown in the official language in which they were submitted.
90~)
ESTER-CONTAINING HALOPOLYALKY~ENES
This invention relates to halogenated poly-
alkylenes whose halo~ens have been partially or totally
replaced by ester groups and to the use thereof as cold
flow pour depressants in middle distillate fuels,
In storage and use of heavy oils, such as
lubricating oils, proklems associated with pour point have
long been in existence and have been recognized in the art.
The pour point of an oil is defined as the lowest
temperature at which the oll will pour or Elow when
chilled without disturbance under specified condition.s.
In the past, it has been discovered that pour-point
problems also exist in the storage and use o-E distillate
fuel oils, particularly at low temperatures. Pour-point
problems arise through the formation of solid or semi-
~solid waxy particles within an oil composi-tion. For
example, in the storage o~ furnace oils or diesel oils
during the winter months -temperatures may decrease to a
point as low as -26 to ~40C. The decreased temperatures
oEten cause crystalli~ation and solidification of wax
inthe dis-tillate fuel oil.
Chlorinated polye-thylenes and ethylene vinyl
ester type copolymers have been employed as cold flow
improvers for hydrocarbon fuels.
The following paten-~ illustrates chlorinated
polyethylenes used as cold flow improvers:
U.S.P. 3,337,313
~i
.~ .
` :~ h
~L2~
-2~
U.S.P. 3,04~,479
U.S.P, 3,093,623
U.S.P. 3,131,168
Often both types do not function equally in the ; .
same fuel. One type may ~e effective in one type of fuel
while the other may be effective in another type oE fuel.
We have now discovered ester-containing!
polyalkylenes prepared by partially or totally replacing the
halo groups of the halopolyalkylenes with e~ter groupsO
We have now'discovered that these ester-
containing halopol~alkylenes are o~ten effective as pour
depressants or improvè cold 1Ow in those ~uels where the
original halopolyalkylenes are not. Thus~ the compositions
of this invention broaden the effectiveness of halopoly-
alkylenes in such fuel.
The starting compositions of this invention
are oil soluble chlorine-containing low molecular weight
polyalkylenes which are essentially ree of crosslinking
and prefera~ly have a.chlorine content of not more than
about 35~ by weight. Polyal~ylenes include polyethylenes
and copolymers of ethylene with mono-olefinic hydrocarbons
having, for example, 3-20 carbon atoms. The,copolymers
pre~erably'have a-t least 50 mole percent ethylene.
The starting chlorine-containing polymers o~
this invention maybe advantageously prepared from non-
chlorina-ted ethylene polymers of low molecular weight but
have an average molecular weight of.at least about 1,000.
They advantageously have average molecular weights in the
range of a~ou-t 1,000-12,000 and preferably, for the
purposes of this invention, about 1,000-7,000. Thay are
chlorinated to a chlorine content of not more than about
40% by weight, and the resulting chlorine-containing
polymers therefore have average molecular weights oE about
1,000-16,000 and preferably about 1,000-9,500.
,,1 ,~, '
~2~
Too high'arl average molecular weiyht in the
polymer may adversely affec-t its.solubility i.n the fuel
oil. Therefore, polymers with very high molecular weiyhts,
such as -those from a Ziegler process, are not considered
suitable for use in this inven-tion in fuel oil.
The average molecular weigh-ts of the above
polymers may conveniently be.determined by means of an
ebulioscope or an osmome-ter. Ano-ther method is by means
of the in-trinsic viscosity of the polymer ~D-1601~to-T in
decalin solvent at 135C).
As sta-ted above, the polymer.or copolymer includes
both polyethylene and copolymers of ethylene with mono-
olefinic hydrocarbons having 3-~0 carbon atoms with the
copolymer having at least 50 mole percent e-thylene.
Advantageously,:the polyethylene tprior to chlorination)
has a brarlch index (number of substituent groups per 100
carbon atoms) of not more than about 5. Advantageously,
the copolymer is one of ethylene with propylene having
(prior to chlorination) a branch index or a-t least 6 and
preferably abou-t 6-20. A very advantageous polyethylene
is one having a branch index of abou-t 2-3 and a molecular
weigh-t of about 2,000. A very advantageous copolymer of
ethylene and propylene is one having a branch index of
about 10-14 and an average molecular weight of about 1,800.
When the ethylene polymers are chlorinated,
na-turally the branch index is increased. However, in
iden-tifying the chlorine-containing polymer i-t has been
found more convenient to describe the chlorine content of
the new polymer in terms o weight percent.
For purposes of this invention, the ethylene
polymers described herein have little, if any~ crosslinking;
although, as described above, they include branched
polymers.
These polymers may be dessribed as being
essen-tially free of crosslinking.
i
--4~
The present invention covers po~yalkylene polymers
or copolymers containing halogen in the amount of 0-35~
and ester groups, the bond between the carbon atoms of -the
poly~lkylene and the ester groups being represented by the
formula
o
O - C - R
C -- C -- C --
~1
wherein R is alkyl, alkenyl, cycloalkyl, aryl, aralkyl,
.alkaryl, R containing 1-30 carbon atoms, the polyalkylene
being essentially free of cross-linking. The polyalkylene
polymers or copolymers are prepared by reacting an halogena-ted
essen-tially linear polyalkylene having a halogen conten-t of
1 up to 40% and a molecular weight of 1000 - 16,000 wi-th a
salt of a carboxylic acid of formula RCOOs~l wherein R is
as indicated hereinabove and replacing the halogen a-toms
wholly or partially with ester groups.
According to one embodiment of the invention, the
polyalkylene is linear pol~ethylene substituted by halogen
and ester groups.
Accordiny to-the preferred embodiment of the inven-
tion, the halogen is chlorine.
According to a specific embodimen-t of the invention,
linear polyethylene of molecular weigh-t about 1500 to 3000,
with a chlorine cont~nt from about 1 to 30% base.d on weight
of polyethylene is used and the ester content is from about
5 to 200~ based on weight of polye-thylene.
The ester groups are from an organic carboxylic acid
which is acetic, propionic, butyric, valeric, hexanoic, hep-
tanoic, octanoic, lauric, palmitic, stearic, oleic, benzoic
or substituted benzoi.c.
,~? .,
s
-5-
The inven-tion also covers the process of preparing
the polyalkylene contc~ning ester groups with 0-35~ halogen
content which consis-ts of reacting a chlorina-ted polyalkylene
polymer or copolymer of molecular weigh-t 1000 - 16,000 with
ca salt of a carboxylic acid in a solvent system which pro-
vides a-t least partial solubility of said halogenated
polyalkylene and the salt of said carboxylic acid.
The invention also covers fuel oil compositions
containing a sufficient amount oE the polyalkylene polymers
or copolymers substituted by ester groups and 0-35% halogen
`atoms to be effec-tive as a pour depressant.
.A~ i`' / ,
The chlorine-containin~ ethylene polymers
usable in accordance with this invention are oil soluble.
Generall.y, this means tha-t -they are completely soluble in
distillate fuel oils in concentrations of at least about
10% by weigh~ (slight hazé is permissable~ at room
temperature (25C~.
However, it is not always necessary that the
non-chlorinated polymers possess good oil solubili-ty.
To illustratel a polyethylene having a lower order of oil
solubility, a crystallinity of about 60-70, a branch index
of abou-t 2-3, and an average molecular weight of about
2,00~ has been chlorinated to produce a chlorine-containing
polymers having good oil solubility, together with
exceptional pour-point depressant properties.
Suitable polyethylene for chlorination are
advantageously products or by-products from the peroxide
catalyzed polymerization of ethylene. Polymerization
reactions using peroxide ca-talysts are well known in the
art and any o these may, for example, be used to produce
the desired pour-point depressor of this invention. The
low molecular weight polyethylene by-products are
usually oily liquid hydrocarbon mixtures, hydrocarbon
greases, or hydrocarbon waxes obtained in small quantities
in the mass polymerizatio~ of ethylene at elevated
temperatures and pressures using a ~ree radical poly-
merizakion catalyst, and such by-products rom poly-
merization catalyzed by the presence o~ peroxides
(or oxygen which form~ peroxides) are particularly
suitable. Another example o a product which may be
used is the homopolymer by-produc-t described by J. W.
Ragsdale, U.S. 2,863,850 paten-ted December 9, 1958.
Other such products are well known in the art.
~Z~90~
The copolymer of ethylene with a
mono-oleEinic hydrocaxbon having from about 3-20 carbon
a-toms has at least 50 mole percen-t ethylene. The mono-
olefinic hydrocarbon includes propylene, butylenes,
pentylenes, hexylenes, and up to 20 carbons, and mixtures
thereof. Preferably, -the mono-olefinic hydrocarbon is
propylene. The copolymers are prepared by methods known
in the ar-t. Advantageously, the copolymer of ethylene
with propylene is prepared by subjecting the combination
to polymerization by peroxide catalyst, or a tetraphenyl
tin-aluminum chloride-vanadium tetrachloride catalyst system
or a te-tra-alkyl lead-vanadium tetrachloride catalyst
system.
Usable polymers for chlorina-tion in accordance
herewith may also be ob-tained by extrac-tion of low molecular
weight polymers having branch indexes hereinbefore defined.
Extraction may be accomplished using a solvent or a solvent-
antisolvent. The extracted polymer is usable if it falls
within the definition of the polymers of this inven-tion as
to characteristics~ Such extracted fraction usually has a
higher branch index and a lower intrinsic viscosity than
the starting material, as well as a higher concentra-tion
oE total solubility in dis-tillate fuels and a lower
crystallinity. Examples of suitable solvents are the
low molecular weight hydrocarbons such as bu-tane, pentane,
hexane, heptane, etc., and example of antisolvents, usable
therewith, are the low molecular weight alcohols such as
methanolr ethyl alcohol, isopropyl alcohol, n-butanol,
etc. Naphtha is a particularly advantageous solvent
because it does not require the use of an antisolvent.
However, because polymers having the desired characteristics
are available commercially and because such polymers can
be "tailor-made" to have the desired characteristics, it
is particularly preferred tc use such polymers which do no-t
need prior extraction. Extraction adds an expensive s-tep
to preparation of the polymers.
.,
8--
Such polymers Eor chlorination as described
above are well known in the ar-t ana are readily available
con~ercially. Many of the usable polymers for chlorina-tion
are obtained as by-produc-ts from commercial polymerization
processes as undesirable low molecular weight ma-terials and
because of their availability and economic attractiveness
such by-produc-t polymers are advantageous for use herein.
The chlorination of these polymers produces
chlorine subs-ti~uen-ts on the polymer chain. These chlorine
substituents increase the pour-point depressant properties
of the polymer ! A preferred me-thod of prep~ring the
chlorine-containing e-thylene polymer oE this invention (and
thereby adding the chlorine substituents on the polymer
chain) is carried out by treating the above-defined
ethylene polymer with chlorine under sui-table reac-tion
conditions to produce the chlorinated ethy~ene polymer.
This process is carried ou-t until the desired chlorine
content of the resulting polymer is reachedO Preferably,
this conten-t is not more than about 35% by weight of the
polymer. Increased amounts o~ chlorine tend to lessen
the pour-point properties of the polymer and therefore
are not preEerred.
The chlorination may be carried out by one oE
several procedures, In one process, chlorine is bubbled
through the molten polymer usually under temperature
conditions of at least 65.5C and advantageously between
65 and 205C. A second process is carried:out by bubbling
chlorine through the polymer suspended in an.inert solvent,
such as carbon tetrachloride (and other chlorinated
methanes, ethanes, and the li]~e) under temperature conditions
o~ at leas-t 24C. The rate of reaction may be accelerated
b~ using an actinis light source~ A third process is
carried out by bubbling chlorine through an aqueous
suspension of -the polymer. The first two proc~sses are
preferred since it is believed that in their use the
chlorine contacts a greater portion of-the inner polymer chain.
9L9 ~)0
_9 _
~t is -to be understood that the chlorine addition includes
the use of known chlorina-ting compounds such as sulfuryl
chloride, oxalyl chloride, phosgene, and the like.
It is fur-ther believed, but again not known
absolutely, that the chlorina-tion of the ethylene polymer
produces the chlorine-containing polymer having the chlorine
atoms wi-th such a distribution on the polymer chain as to
provide exceptional pour-point depressant properties in
the polymer.
The ~hlorination i5 carried out to produce a
chlorine-containing polymer having preferab~y less than
about 35% chlorine by weight. More preferable and op-timum
chlorine contents are dependent somewhat on the par-ticular
polymer being ¢hlorinated. To illustrate, a polyeth~lene
having a branch index of no-t more than about 5 and a
molecular weight of about 1,500-2,500 is preferably
chlorinated to a chlorine content of about 10-30% by
weigh-t. More optimum pour-point depressant properties
for this polymer result when it has an average molecular
weight of about 2,000, a branch index of about 2-3, and
a chlorine content of about 16-23% by weight. Another
illustration is a copolymer of ethylene and propylene having
a branch index o~ about 6-20, an average molecular weight
oE about 1,500-2,000, and a chlorine con-tent of about 4-13
by weigh-t. More optimum pour-point depressant properties
are obtained when this polymer has a branch index of about
10-14; an average molecular weight of about 1,800, and a
chlorine content of about 8-11% by weight. More exact
values Eor these ranges are dependent on the particular
fuel oil being utilized.
We have discovered that the halopolyalkylenes
can be converted to ester-containing halopolyalkylenes
by replacing the halo- ~roups with carboxylgroup so as
i
~,~
~...
~2~ 3()~
--10--
to yield ester groups
O .
Cl O ~-C-R
-C -C - C- ~ R C O M~ C-l - C ~ ~ M ~ Cl
~ H
where R is a hydrocarbon group, for example alkyl,
alkenyl, cycloalkyl, aryl, aralkyl, alkaryl, etc., where
R has from 1 to 30 carbons.
Suitable carboxylic acids include the following:
acetic, propionic, butyric, valeric, hexanoic, heptanoic,
oc-tanoic r lauric, palmitic, s-tearic, oleic, benzoic,
substituted benzoic acid, olefinic acids.
The preferred carboxylic acids are alkane-
carboxylic acids having from 1-30 carbon atoms but
preferably from 1-18 carbon atoms.
In practice, the carbo~ylic acids are reacted
in salk forms such as sodium, potassium,etc., salts.
In the compositions of this invention, at least
about 1~ of the halogens are replaced, such as from abou-t
1 to lnO% of the halogens replaced, for example fxom
about 10 to 80% of the halogens replaced, but preferably
from about 15 to 75~
Where all chlorines are not removed the structure
of the product is a combination of chlorinated polye-thylene
and ethylene vinyl ester copolymer in the same molecule.
In addition, there is olefinic unsatura-tion due to elimina-
tion oE IICl. NMR analysis gîves a quantitive determination
of the structure since it de-termines the ratio of chlorine
to ester to olefin because the adjacent hydroyens to those
structural groups are well separated in the NMR. The
products contain the following groups:
-11~
Cl o - C - R ~ I
-- C -- 1 -- C -- . . , ~ C = C --
~) '' (~ '
The product has a unique s-tructure of a partially
chlorinated e-thylene-vinyl ester copolymer with some
olefinic unsaturation in the backbone. In the case of
linear polyethylene these materials differ radically from
normal EVA structures because the backbone is totally
linear while ethylene-vinyl ester copolymers have
subs-tantial branching.
~ problem tha-t exists is that the mild basici-ty
of sodium carboxyla-tes leads to a certain amount of
elimination of HCl from the backbone of the polymer to
form internal olefin. This reaction competes with the
substi-tution reaction. The forma-tion of internal oleEin
is known to be harmful to its cold flow activity and this
side reaction must be r; nim; ~ed. This elimination side
reaction varies depending on temperature, solvent and
structure of tha carboxylate anion. It is difficult to
eliminate this reaction completely and as far as cold
flow activity is concerned we have to make up in
substi-tution what we lose by olefin formationO In
general the ratio of substitution to elimination ranges
from 3/1 to 6/1.
The conversion of chlorinated polye-thylene to a
chlorinated ethylene-vinyl ester type copolymer or a
halo~en-free product is not a simple task because the sodium
salts of carboxylic acids are not soluble in the common
nonpolar solven~s that dissolve chlorinated polyethylene.
This incompatibillty problem can be handled in three ways.
49~
-12-
1. The reaction can be carried out in a
nonpolar solvent in the presence oE,a crown e-ther (such
as 18-crown 6) which essen-tially solubilizes the me-tal
ion carboxyla-te in-the organic medium and allows for a
homogeneous reaction.
2. The reaction can also be carried out in
the presence of a phase transfer catalyst system. This
entails dissolving the sodium carboxylate and an oil-
water soluble quaternary ammonium compound in water and
conducting a two phase reaction with the chlorinated
polyekhylene dissolved in a nonpolar organic solvent.
-The reaction proceeds because the quaternary ammonium
salt transfers the carboxylate anion as part o~ its own
structure to -the organic phase so that the actual
reaction proceeds homogeneously.
3. The reaction can be carried ou-t in a solvent
mixture where there is partial solubility of both the
¢hlorina-ted polymer and the salt of the organic acid.
The first two reaction methods are less
economical because of the high cos-t of crown e-thers
and quaternary ammonium compounds. ~.ethod 9 is the
most economical]y commercial.
We have found that blends of alcohols, and
blends of alcohols and ketones ("Ethyl Cellosolve"/methyl
isobutyl ke-tone, methyl carbitol/diisobu-tyl ketone) allow
us to conduct the displacement reaction in an effective
manner.
The following examples are presented for purposes
of illustration and not of limit~tion. The chlorinated
polyethylene employed herein is a chlorina-ted linear
polyethylene having a molecular weight of about 2000 and
a weight % chlorine content o about 24%.
,~
4~:~0~
-13-
Example 1
A mixture oE 20 gms chlorinated linear poly-
ethylene, 24 gms of potassium ace-tate (.153 mole) and
2 gms (~00756 mole) of 18 crown-6(1,4,7,10,13,16,-hexa-
oxacyclo-oc-tadecane) was stirred in 30g of Solvent 14.
The -total was heated at 130C for 24 hours. The reac-tion
mix-ture was cooled slightly and fil-tered. Evaporation
of the solvent lef-t a waxy residue. An infrared spectrum
of the residue showed strong carbonyl absorption a-t
1740 cm~l. The proton NMR showed the following:
(CC14 solvent, TMS in-ternal standard) 1.'24 ~(mul-tiplet, CH2~
1.96d~(sing1et, O-C-CH3) 3.58 ~(singlet, crown ether CH2's)
3.82 (CHCl) 4.77df(CH-O-C-CH3) 5.32 of(olefinic CI12).
The following is the analytical determination of the extent
of reaction by integra-tion of the respective CH absorp-tions.
Cl~ ~ ester, % Olefin = 15:70:15.
Example 2
A mixture of 20.0g chlorinated linear poly-
ethylene, 17.0g (0.207 mole) of sodium acetate, 100 ml
of methyl isobutyl ketone, 10 ml o;E water, and 2.4g
(.0066 mole) of hexadecyl-trime-thylammonium bromide was
stirred and heated in a stainless steel reactor at 125C
for 3 days. The reac-tion mixture was then cooled and
250 ml of methanol was added and the mixture stirred for
15 minutes. The methanol portion was decanted and this
washing process was repeated three times. The residue
was then transferred to a 400 ml beaker and dissolved in
cyclohexane and toluene by heating and stirring. The
mixture was filtered and evapora-tion of the solvent rom
a sample of the filtrate left a waxy residue. The IR
and NMR spectra had characteristic absorptions similar
to those of the previous example and the following
relative analysis was determined from the NMR spectrum~
% Cl: % Ester: ~ Olefin - 51:39:10.
~.
~ ,~
o~
Examp~e 3.
~ 13 gms of lauric acid was dissolved in 90 mls
of'~utyl Cellosolve"and 15 mls of ethylene glycol. To
this was added 3~5 gms of sodium methoxide and the mixture
was heated -to 120DC until it became clear (forma-tion of
sodium laurate). 20 gms oE chlorinated linear poly-
ethylene was added and the reaction was stirred vigorously
at 145C for 22 hours. The reac-tion was cooled and a
large excess of methanol was added to precipitate the
polymer. The polymer was washed with met.hanol and then
redissolved in.cyclohexane. NMR analysis.shows the
following results~ % Cl % Ester: ~ Olefin = 54:35:10.
- EXample 4
19 gms of lauric acid was dissolved in 100 mls
of methyl.carbitol and 25 mls of diisobutyl ketone. To
this was added 5.1 gms of sodium methoxide in order to
form the sodium laurate. 20 gms of chlorinated linear
polyethylene was added and the reaction was heated at
155~C for 24 hours. The polymer was precipita-ted in
methanol, washed and redissolved in cyclohexane. NMR
analysis shows the ra-tio o~ ~ Cl: ~ ~ster: ~ Olefin
45:43:12.
Example 5
Using the same reaction conditions as Example 4,
the following acids were used for conversion to thei.r
sodium salts and subsequen~ displacement of chlorines
~rom chlorinated polyethylene
(a) propionic tb) octanoic acid
(c) oleic acid (d) s-tearic acid.
The ester-containing chlorine-containing
ethylene polymers of this invention are very useful for
depressing pour points of :Euel oils. Most hydrocarbon
uels yield crystals of solid wa~ as their temperature
is lowered below the cloud point. In a usual distillate
fuel oil composition containing a pour-point depressant
addition agent, the crystals of solid wax do not hinder
. .,
g~
~15-
flow through pumps, Eilters,.screens,.e-tc., even at
temperatures well below the pour point of the. base oil,
Eor example, dis-tilla-te Euel oil. In such cases the
crys-tals are small and therefore do not hinder flow.
However, in some fuel blends the crystals which form are
sufficiently large and dense.so tha-t an immobile layer of
crystals is formed at the bottom oE storage tanks.
Such crystals of solid wax are not susceptible to
treatment by most pour-point depressants tailored for
distillate fuels and the crystals can therefore cause
severe flow problemsO The flow problems arise when it
is attempted to pump the fuel from one location to another.
Pump parts, filters, and~the like tend to become clogged
with the crys-tals of solid wax which concen-trate in the
fuel oil at the bottom of storage tanks. The polymers
of the present invention, when used as pour-point
depressants, serve to improve the pumpability of a
distillate fuel oil, normally tendiny to produce wax
crys-tals of sufficient size and densi-ty (formed even
in the presence of conventional pour-point depressant
to inhibit pumpability, in addition to lowering the
pour point).
The polymers of this invention advan-tageously
imp~ove pumpability; for example, a chlorine-containing
polyethylene of the above-defined characteristics is
very active in modifying the wax crys-tals formed in or
precipitated from troublesome fuels normally tending to
form large dense crystals at lower temperatures. Although
the ~ormation o~ the wax is not actually inhibited when
using the polymer additive of.this invention, the wax
appears as a vary finely divided ~luffy material which
should be pumpable under most conditions.
~,
~ ~ .
~2~90~
16-
The fuel oil composition of this invention
comprises a major amount of a dis-tillate fuel oil and as
an improved pour-point depressan-t, a small but effective
amoun-t of -the above-defined chlorine-containing ethylene
polymer. Usually the chlorine- and ester containing
polymer is present in an amount ~rom about 0.001 to about
5 weight percent, advan-tageously ~rom about 0.001 to
about 0.1 weight percent, and preferably from about 0.005
to about 0.03 weight percen-t. The chlorine- and es-ter-
containing polymer may be added directly to the fuel oil
or may be formulated in concentrated form ~n a hydrocarbon
solven-t such as benzene, toluene, xylene, and the like.
Additional suitable solvents are more specifically
described hereinbelow.
The fuel oil is a hydrocarbon oil such as,
for example, a diesel fuel, a jet fuel, a heavy industrial
residual fuel (e.g. Bunker C), a furnace oil, a hea-ter
oil fraction, kerosene, a gas oil, or any other like
ligh~ oil. O~ course, any mixtures of distillate oils
are also intended. The dis-tillate fuel oil may be
virgin and/or cracked petroleum fractions. The distillate
fuel oil may advantageously boil in the same ranye of
from about 120 to about 400C. The distillate fuel
oil may contain or consist of cracked components such
as for example, those derived from cycle oils or cycle
oil cuts boilin~ heavier than gasoline, usually in the
ranye of from about 230 to about 400C and may be derived
by catalytic or thermal cracking. High-sulfur-containing
and low-sulfur-containing oils such as diesel oils
and the like may also be used. The distillate oil may,
of course, contain other components such as addition,
agents used to perform particular functions, for example,
rust inhibitors, corrosion inhibitors, antioxidants,
sludge stabilizing compositions, etc.
-17-
The preferr~d distillate fuel oils have an
initial boiling point in the range of from abou-t 120 to
abou-t 246C and an end poin-t in -the range of from about
260 -to about 400C. The dis-tilla-te Euel oil may
advantageously have an A.P.I. gravi-ty of about a-t least
30 and a flash point ~Tag closed cup) not lower than
about 43C and preferably above about 46C.
The ester-containing chlorine-containing
polymers of this invention may, for convenience, be
prepared as concentrates as additives for fuels.
Accordingly, the polymer is dissolved in a'suitable
organic solven-t therefor in amounts greater than 10% and
preferably from about 10% to about 75%. The solvent in
such concentrates may conveniently be present in amounts
rom about 25-~ to about 90~. The organic solvent
preferably boils within the range of from about 38C
to about 372C. The preferred organic solvents are
hydrocarbon solven-ts, for example, petroleum fractions
such as naph-tha, heater oil, mineral spirits, and the
like; aroma-tic hydrocarbons such as benzene, xylene
and toluene; paraffinic hydrocarbons such as hexane,
pentane, etc. The solvents selected should, of course,
be selected with regard to possible beneficial or adverse
effects they may have on the ultimate fuel oil composition.
Cold flow activity is determined according to
the procedure of ASTM D 97.
i ~
!
~Q~10~
-18-
Table 1~
Cold Flow Activity
C~undsOil A Oil B Oil C Oil D
ppm0 300 600 800 0 ~00 600 0 -300 ~00 0 600 900
Oom~rcial
EU~-5 -15 -~0 -~S ~20 -10 -10 : -5 -~S -40
*Linear
Chlorina~ed
Polyethyl~ne -5 -10 -10 -10 -~20 - O - B ~25 -15 -15 -5 - 5 -10
.Example 1 -5 -10 -5D -50
Example 3 -S -10 -10 -S0 ~0 -10 --20 -~25 -20 -40 .
E~ample 4 . ~ - 5 - 5 -25
*This linear chlorinated polye-thylene was that employed as
a s-tarting material in preparing the chloro-esters of
Examples 1, 3 and 4.
; . . Table 2 . .
Cold Filter Plugging Point ~CFPP) IP309/~0*
- . Oil A . Oil B Oil C
,
CFPP Blank C -5 ~5 ~10
Compounds
PPM 1500 . 1950 1750
Commercial E~A~ 10 -1 ~ 5
Commercial EVA-2 -11.5 -3 . ~ 1
Chlorinated Polye-thylene - 8 . .-~2 ~ 5
Example 5D -14 ~3 - 5.5
Example 5B . . 1~.5 -6 - 8 .
I
.; ~ .
~i f 3~ s o ~
-19-
* IP sook of Standards, pp. 309.1-3.09.6. The CFPP is
defined as -the highes-t tempera-tuxè ~expressed as a multiple
of 1C) at which fuel, when cooled under prescribed
conditions, either will not flow through the filter or
requires more -than 60 seconds for 20 ml. to pass through.
Irable 3
Low Temperature Flow Test (LTFT)*
.. . Oil A (Cloud - 24.4C)
Compound ~ . ~ PPM . LTFT Flow (-27.dC)
Commercial ~VA . . 2000 - Fai.l
. 2250 Fail
Chlorinated Polyethylene 2000 Fail
. .2250 Fail
Exampl.e 5C 2000 26 seconds
Example 1 - . 2250 25 seconds
Example 5A . 2250 33 seconds
. Oil B ~Cloud -17.~C)
. ' LTFT Flow (~21~1C)
Commercial EVA 200 Fail
300 Fail
400 38 seconds
Chlorinated Polyethylene 200 - Fail
. 300 Fail
- . . 400 . Fail
Example 5C - 200 .Fail
300 . 34 secollds
` 400 - 30 seconds
* rrest developed by Exxon Research and Engineering Co. to
determine the low.temperature operabiiity of diesel fuels
in autodiesel equipment. Diesel fuels passing the test
are expected to provide satisfactory operability (free
of wax plugging) in autodiesel equipment at fuel
temperatures equal to or higher than that of the test.
Low temperature operability of the test fuel at a given
j,
.... ~
30~
-20-
temperature is considered satisfactory iE passage of the
fuel -through a prescribed screen ls comple-ted in less -than
60 seconds.
In summary, this invention relates to halogenated
polyalkylenes whose ha.logens have been wholly or partially
replaced by es~er groups. The preferred polyalkylene is
polye-thylene and the preEerred embodiment thereof be.ing
a linear polye-thylene.
The polyethylenes have a molecular, weigh-t of
from about 1000 to 30,000, such as from about 1500 to
10,000, bu-t preferably from about 1500 to 3000, and a
halogen content of f.rom about 1 -to 40, such as from about
5 to 30, but preferably from about 10 to 25.
The percent of halogens replaced with ester
groups can vary from about 1 to 100, such as from about
10 to 80, but preferably from about 15 to 75.
The invention also relates to the use o the
above compositions as pour depressant or cold flow
improvers.
The amount of pour depressant employed based
on wgt. of Euel is from about 1 to 2000 ppml such as from
about 10 to 1800 ppm, for example from about 50 to 1800 ppm,
but preferably about 100 to 1500 ppm.
