CA2135136A1

CA2135136A1 - Cloud point depressant composition

Info

Publication number: CA2135136A1
Application number: CA002135136A
Authority: CA
Inventors: Gregory L. Hiebert
Original assignee: Gregory L. Hiebert; The Lubrizol Corporation
Current assignee: Lubrizol Corp
Priority date: 1993-11-09
Filing date: 1994-11-04
Publication date: 1995-05-10
Also published as: FI945203A; JPH07188501A; NO944198L; EP0654526A2; NO944198D0; FI945203A0; EP0654526A3

Abstract

ABSTRACT OF THE DISCLOSURE
A composition of a polymer of an 8 to 40 carbon hydrocarbyl ester of an ethylenically unsaturated acid, short chain ester-containing monomers, and short chain alkyl ether monomers; and a mixture of hydrocarbyl-substi-tuted polynuclear aromatic compounds, is effective to reduce the cloud point of paraffinic liquids.

Description

~ 2135136 ~
.

26nRt~ TITLE
CLOUD POINT DEPRESSANT COMPOSITION
BACKGROUND OF THE INVENTION
The present invention relates to a composition useful for reducing the cloud point of paraffinic liquids.
When diesel fuels, home heating oils, and other paraffinic liquids are cooled, solidification occurs progressively, normally over a range spanning some 10 to 15 C. This solidification is generally undesirable for materials which are normally handled in the liquid state, and efforts to measure and ameliorate this phenomenon have been pursued. Cloud point is the measurement of the temperature at which paraffin crystals firs~ appear when such a material is cooled. This value is determined by standardized methods such as ASTM D 2500. The cloud point of a particular material depends on the paraffin (particu~
larly n-paraffin~ concentration in the liquid, on the molecular weight of the particular paraffins, and on the chemical nature of the non-paraffin component of the liquid~ For instance, the presence of higher molecular weight paraffinic molecules generally leads to higher cloud points. At temperatures below the cloud point, the materi~
al becomes increasingly solid, until the pour point (ASTM
D 97) is reached, tha~ is, the temperature at which the material has essentially solidified. Although there are many materials which are known to be suitable as pour point depressants, a reduction of cloud point is considerably more difficult to achieve. The present invention provides for the reduction of the cloud point of paraffinic liquids, thus permitting!the wider use of paraffinic liquids as fuel and lubricants, particularly at low temperatures.
A fuller discussion of the phenomenon of cloud point, including the measurement thereof by differential scanning calorimetry, is found SAE Technical Paper Series No.
861527, "New Additives for Diesel Fuels: Cloud-Point Depressants," Faure et al., 0ctober 6-9, 1986. This paper also discloses the use of copolymers of linear ~-olefins ~ '" - '. .:. ' ., ~` 21~3~

' with acrylic, vinylic and maleic unsaturated compounds as additives to reduce cloud point.
U.S. Patent 2,491,683, Munday et al., December 20, 1949, discloses a lubricant composition consisting of a major proportion of waxy mineral lubricating oil having dissolved therein about 0.07 to 0.20 % of a wax-naphthalene pour depressor (the condensation product of 100 parts chlorinated paraffin~ wax with~naphthalene) and 0.05 to 0~.25% of a polymeriæation product ~e.g. a copolymer) of fumaric acid esters of mixed alcohols obtained by hydroge-na~ion of coconut ~o~ Small amounts o~ the additive mixture give better results~ in depressing pour point than do either component individually.
; U.S. Patent 3,475,321, Henselman et al., October 28, ~ 1969,~ discloses~ solvent dewaxing using a synergistic dewaxing~ald of a mixture of ;vinyl~ester polymer and chlorinated wax-naphthaléne Friedel-Crafts condensation product. ;~; The condensation~product ~1s prepared by the reacti~n~of a halogenated~paraffln with~an~aromatic hydro~ 5 ~20 ~ carbon. ~The haloge~atèd paraffin may, for example, contain from about~8 to about ~O ~carbon atoms.~ The aromatic hydrocarbon is~ preferably ~naphthalene. The~ vinyl ester po ~ er~is~contalns~long~chain vinyl esters monomers, e.g.
containing substantially l~inear alkyl~side chains of at ;25 . least I} carbon atoms.
U.S~ Patent 4,43~9,~308,~Gudelis et al., March 27, 1984, discloses~ a procéss~for~solvent ~dewaxing~of bright~stock~
waxy raffinate oil. The dewaxing aid is a mixture of poly `di-àlkyl ;fumarate/vlnyl~acetate copolymers and~ a wax~
30~ naphthalene~condensate.~ The~;condensate has a molecular weiqht~of about l,~OOO~and greater.~
SUMMARY OF THE INVENTION
The~present~inventlon~provldes a~compositlon~compris-ing~(a) a polymer~of (i)~;a hydrocarbyl~ester of an ethyl-35 ~; enical~ly unsaturated;~acid-of 3~to 6 carbon atomsj~wherein the~hydrocarbyl group contains about 8 to about 40 carbon ~ ~ 213~136 atoms, ~iij an ester-containing monomer selected from the group consisting of alkyl esters of ethylenically unsatu~
rated acids o~ 3 to 6 carbon atoms wherein the alkyl group contains fewer than 8 carbon atoms and vinyl alkanoates wherein the alkanoate group contains up to about 8 carbon atoms, and (iii) an alkyl ether monomer wherein the alkyl group contains up to about 8 carbon atoms: and (b~ a polynuclear aromatic material, substituted on at least one ring with at least one hydrocarbyl group having about 8 to about 20 carbon atoms and with at least one hydrocarbyl group having about 21 to about 4Q carbon atoms, wherein the amounts of components (a) and (b) are such that the composition, when added to a paraffinic liquid, pro-vides a reduction in the cloud point thereof.
The invention ~urther provides a method for reducing the cloud point of a paraf~inic liquid, comprising adding thereto an effective amount of such compositions; and further such compositions such additives in paraffinic liquids.
DETAILED DESCRIPTION OF THE INVENTION
The first important component (a) of the present inven~ion is a polymer of a hydrocarbyl ester of an ethyl~
enically unsaturated acid. This is a polymer which has a substantially carbon chain backbone derivable from the addition polymerization of àn ethylenically unsaturated acid and other comonomers, described below. The polymer-ized acid groups are at least partly and preferably sub-stantially completely in the form of hydrocarbyl esters;
reference h`erein to polymerization of acids is not intended to be limiting to the use of the actual acid in ~he poly~
~erization reaction, but encompasses polymerization of esters and ather materials which can be converted into esters, including anhydrides and acid halides.
The acids which are capable of polymerization are genera.ly those ethylenically unsaturated acids having 3 to 6 carbon atoms, including those with ~ ethylenic unsatur-~ 2~3513~

ation. Specific materials include acrylic acid, crotonic acid, methacrylic acid, ethacrylic acid, fumaric acid, maleic acid, itaconic acid, and citraconic acid and their reactive equivalents. The diacids are preferred, and of these fumaric acid is most pre~erred; the corresponding dialkyl ester is a dialkyl fumarate. It is understood that maleic acid and fumaric acid become sub~tantially equiva-lent after they are polymerized, since their double bond becomes a single bond during the polymerization reaction.
However, details of the stereochemistry of the resulting polymer may in some cases differ depending on whether maleic (cis) or fumaric (trans) monomer is used. In some instances it may be more convenient to use one material rather than the other; maleic acid, for example, can form a cyclic anhydride which can be polymerized as such, while fu~aric acid cannot. Generally, however, references herein to polymers of fumaric acid or ~umaric esters are intended to include polymers similarly derived from maleic acid, maleic anhydride, or maleic esters.
The polymer can be prepared directly from the ester of the acid, or it can be prepared from the acid itself or (in the case of certain diacids) the anhydride or other reac-tive monomers. If the polymer is prepared from one of the materials other than the ester it can be converted into the ester form by reaction of the polymer with a suitable alcohol or by other well-known reactions.
The alcohol with which the acid monomer or the poly~
meric acid functionality is reacted to form the ester is an alcohol with a hydrocarbyl chain containi;ng 8 to 40 carbon atoms, more preferably 10 to 28 carbon atoms, and most preferably 12 to 14 carbon atoms. The hydrocarbyl group need not be derived from a single alcohol of a single chain length, however, but can be derived from a mixture of alcohols if desired, provided that at least some of the chain lengths of the alcohol portion are within the desired range. Moreover, the specific chain length of the hydro~

`" 2~35~36 carbyl groups can be selected to correspond to the type sf paraffinic fluid in which the polymer is employed, as described in more detail below.
The polymer of component (a) also contains other mono-mers derived from ethylenically unsaturated compounds.
These comonomers are, first, short chain ester-containing monomers. Examples of short chain ester-containing mono-mers include vinyl alkanoates where the alkanoate moiety contains up to ~ carbon atoms and preferably up to 4 carbon atoms, such as vinyl acetate, vinyl propionate, and vinyl butyrate. Other examples are short chain esters of unsatu-rated acids, having fewer than 8 carbon atoms, and pre~er~
ably up to 4 carbon atoms in the alcohol-derived moiety.
Such short chain esters include methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, propyl acrylate or methacrylate, and n-butyl, t-butyl, and isobu-tyl acrylate or methacrylate. Secondly, the polymer of component (a) contains short chain alkyl ether comonomers, where the alkyl group has up to 8 carbon atoms and prefera-bly up to 4 carbon atoms. Examples ar~ the alkyl vinyl ethers such as ethyl vinyl ether, propyl vinyl ether, and the butyl vinyl ethers. 2xamples of suitable polymers ;:. ., include terpolymers of fumaric esters with vinyl acetate and ethyl vinyl ether, terpolymers of fumaric esters with ~
vinyl propionate and propyl vinyl ether, terpolymers of : `-fumaric esters wikh methyl acrylate and ethyl vinyl ether, and terpolymers of fumaric esters with n-butyl acrylate and ;~
propyl vinyl ether. Preferred polymers are terpolymers of !, ! I fumaric esters with vinyl acetate and ethyl vinyl ether, the latter comonomers being in relative molar amounts of 1:9 to 9:1. Preferably each of the latter comonomers will comprise a minor portion of the polymer, typically 1 to 15 percent by weight and preferably 3 to 10 percent. Particu ~ ~`
larly preferred polymers are described in greater detail in U.S. Patent 3,250,715. --" '' :~ ' :, ~J~

., .

The polymer of component (a) may also contain other copolymerizable monomers such as the ~-olefins, including ethylene, propylene, or styrene, as well as carbon monoxide or sulfur dioxide. The amount of these and other supple-mental comonomer~, if any, is preferably sufficiently lowthat the pol~mer substantially retains its character as a hydrocarbyl alkenoate polymer, modified by the presence of the above-defined comonomers.
The polymers of component (a) can be prepared by known }0 methods. In a preferred case di-(C12-Cl4) fumarate i5 mixed with an appropriate amount of vinyl acetate and ethyl vinyl ether. The polymerization is carxied out by mixing and heating the reactants with or without a solvent or diluent in the presence of a small amount of an initiator at a temperature of from 25C to 150~C, preferably up to 100C.
Since the polymerization is exothermic, cooling may be required to maintain the reaction mixture at the desired temperature. It is often convenient to add one of the reactants to the other reactant or reactants over a period of time in order to control the rate of the reaction.
The polymerization can be carried out in the presence of a small amount of an initiator such as an organic peroxide or azo-bis-isobutyronitrile. Organic peroxides such as benzoyl peroxide are especially useful. Generally 0.01 to 1.5% of the initiator is used.
The reaction time will vary from 1 to 30 hours depend~
ing on the temperature, reactivity of the monomers,- and other reaction conditions. The polymerization can be run ' cbntinuously or`batchwise. Details o~ such polymerizations are well known to those skilled in the art and are reported in greater detail in U.S. Patent 3,250,715.
The molecular weight~of the resulting polymer will depend on a variety of factors under the control of the skilled operator, including concentrations of monomars and catalyctO ~The polymer of the present invention ordinarily . .

~ 2135~l36 . . . . .

- , :, , , -- :

has a weight average molecular weight of 3,000 to 300,000, generally 5,000 to lO0,000, preferably about 20,000.
The second important component (b~ of the present invention i6 a compound with fused aromatic rings, that is, polynuclear aromatic compounds in which the aromatic rings share at least one side. The polynuclear aromatic compound is substituted on at least one such ring with at least one hydrocarbyl group having chain length defined below.
Typical fused ring aromatic systems include ~aphthalene, with two rings, anthracene and phenanthrene, with three rings, and naphthacene, chrysene, triphenyl~el and pyrene with four rings. ~Naphthalene is the preferred fused ring aromatic hydrocarbon.
The polynuclear aromatic compound is substituted on at least one ring by at least one hydrocarbyl group having 8 to 40 carbon atoms. The overall composition of component (b) is such that it contains a mixture of hydrocarbyl substituents of different lengths. The different hydrocar~
byl substituent may appear on a single aromatic molecule or on different molecules within the mixture. Alternatively, component (b) can be a mixture of different types of molecules, some having one type of hydrocarbyl substitu~
tion, some having another, and some having mixed types of substitution on the same mole~cule.
The substitution of the material of component (b) comprises a fraction of relatively shorter chain hydrocarb~
yl groups, containing 8 to 20 carbon atoms, and a second fraction of relatively longer chain hydrocarbyl (or hydro-; I i carbylene~groups, containing 21 to 40 carbon atoms. The longer chain groups are preferably derived from chlorinated `~ hydrocarbons or are materials of similar structure although derived from precursors other than chlorinated hydrocar-bons. Chlorinated hydrocarbons typically contain at least a fraction of molecules which are polychlorinated, which fraction can result in hydrocarbylene substitution on the aromatic molecules, that isj formation of hydrocarbylene ~ 2~35~3~
.`, ...
" ~ ,, . ~

linkages among aromatic nuclei. (As used herein, the term "hydrocarbyl" is to be construed to include hydrocarbyl-ene). Formation of hydrocarbylene linkages increases the effective molecular weight of the molecules. In the preferred material at least a portion of the aromatic nuclei are so linked. The polyfunctional reactants which lead to hydrocarbylene groups~ and the linkage of aromatic moieties preferably contain at least about 14 carbon atoms, and more preferably at least about 22 carbon atoms. That 0 ~ :i5, preferably the polyfunctional reactants constitute the longer ~hain fraction~of the hydrocarbyl substituents.
The~ relative weight ratios of the ~horter chain hydrocarbyl substituents to the longer chain hydrocarbyl ~ubstituents are preferably 10:1 to 1:1, and more prefera~
15~ ~ bly 5:1 to 3~
The hydrocarbyl group or~groups are preferably alkyl (or alkylene) ~roups. Alkyl or~alkylene groups can be attaahed to an aromatic ring by any of a variety of meth~
ods~,; the commonest being known as the Friedel-Crafts 20~ reaction.~ A~chlorinatcd~alkane~or a~ chlorinated wax, for example,~ aan be condensed ~with the~aromatic ring in the presenae~of an appropriate amount~of~inert solvent, using ; a~small amount of~a~catalyst such as aluminum chloride. A
chl inated~materlal;~with a~ single ~chlorine ;atom will 25 ~ provlde~an~alkyl~cha~in:~a material~with~;~ultiple chlorine atoms will~provide~alk lene substitution and l~in age~of multiple~aromatic~irings~into an oligomeric or polymeric structure. Alternatively, the starting material can be an oiefin~whiich is~reacted ~wit~ aluminùm chloride in !situ.
3~0 ~ m e reaation can~be~started~at room~temperature~and, after~
the~catalyst and~reàctants have all been mixed, the reac-tion~mixture~can~be~heated to a~final temperature of 30 to lOO~C.~ A~ter~the;;reaction has been completed ~(generally ;reg~ir~ng~l/2~hour~to~10 hoursl; residual~catalyst ~can be 35 ~ : hydrolyzed~; by addlng~: ~;wat2r and~ bAse and the~ cataly8t removed~;by ~an appropriate method such as filtration or `~ 213~6 ..... ~ ' ~,' '' , :, ' '; ',,,:
washing with water. The product can be purified if desired by known methods, although this may not be necessary.
In a preferred embodiment, an alkylation of naphtha-lene ~s conducted using a chlorinated alkane having a molecular weight of about 242, that is, having a carbon chain length of about 24, followed by a commercial mixture of C16 to Cl8 ~-olefins. The product is naphthalene having mixed 16-18 and about 24 carbon alkyl substitution and is believed to be a mixture of mono- and poly-alkylated materials. It is further believed that the product also contains a fraction of material with naphthalene nuclei which are bridged by alkylene chains derived from alkyla-tion of the naphthalene by di- or polychlorinated alkanes.
Such bridqed materials may he considered polymeric materi~
als, the term being interpreted broadly to include oligo-maric materials containing e.g. 2 or 3 or several aromatic groups as well as structures with higher molecular weights.
Such materials are included within the definition of hydro-carbyl~sub tituted aromatic compounds, and in such cases the hydrocarbyl substituents are to be construed to contain the number of carbon atoms contained in the chlorinated alkane, that is, discounting the effects of the polymeriza-tion.
The relative amounts of ~omponents (a) and (b~ are such *hat the combination, when added to a paraffinic : liquid, provides a reduction in the cloud point of the liquid. In practice is has been found preferable in some cases to use a modest excess of tbe hydrocarbyl-substituted aromatic compound. Thus generally components (a) and (b) are used in rela ive amounts of 90:10 to 5:95 by weight;
preferably the relative amounts o~ components (a~ and (b) are 80:20 to 10:90, and most preferably the relative amounts are 50:50 to 20:80.
Components (a) and (b) (and any further optional compon^nts, described below) can be combined by any convenient means, or they can be added separately to a ; .

, 213~13~
!

paraffinic liquid. Combining of the components can be e~fe~ted by blending at ambient temperatures with moderate mixing for 10 minutes to 2 hours, typically about 30 minutes. Gentle heating, to e.g. 50-80C (preferably about 65C) often improves the ease of mixing.
Components (a) and (b) are ~added to a paraffinic ~` liquid and serve to reduce its cloud point. Paraffinic liguids include reflned and unrefined petroleum, including ~1 condensate crude oils (oils~ obtained~from gas wells, ;~; 10 comprising predominantly low~ molecular weight materials ;~with`a high molecular weight fraction). Crude petroleum contains a wide variety of~ componénts, in particular alkanes having up~ to about~ 28 carbon atoms and above.
Among the fractions derived from~crude oil by distillation ~ are middle~distillàtes, loosely~characterized by ~normal boiling points~of 177-454C (350-850F), and diesel~fuels, loosely~characterized~by normal boiling pcints of~l77-343C
(350-650~F).~ These~boil~ing~points~ correspond roughly to those~of~a1kanes in~th~e;C~2~to~C~8 rangè~for middle distil~
' 20 ~;1ates~and~the;Cl2~to~Cl6~range;~for d~iesel fuels.
The~ present; inYention is~ also applicable~to lighter distil~lation~cuts~including~gasoline~or~naphtha,~as vell~as to~synthetic~oils whicb~have~a~paraf~finic component. ~Such i;c~ oils~ include~thosé ~made~ by ~polymerization of 25;~ olefins~or~other~ unsaturated~'aliphatic olefins.~ The invention~is~applicable¦to~paraffinic~liquids which can~be~
used~;as~l ~ ricants~ as'~fuels,~as~;func~tional fluids~(includ~
ing hydraulic fluids), or for~any other use. ~ 'i.f.,~
"~'The~ch;àin~llëngtha~of~the~substituënts of~compcnents 30~ ~ (a~ and~(b)~are preferably~sel~ected~to correspond~, at least~
approximately~,~ to~the~length~of the;~carbon chains~in~the paraf~f~inic~ iquid~ That~is~ when ~the~composition~is used ;as~a Gloudlpoint dèpre~ssant;in~a~die~el;~fuel, the hydrocar~
byl or alkyl~groùps~in the~alcohollc-derived moiety~cf the~
35~ ester group~préerably contain~10 to l6,~and more prefera~
bly 12`to~14~càrbcn~atoms. When the~composition;is~used~in ~;` 213513~

, , . .
11 - ,.. ...
other middle range distillates, the alcohol-derived moieties can preferably contain 12 to 20, and more pre~era-bly 14 to 18 carbon atoms. For higher boiling fractions, the alcohol-derived moieties can contain 18 to 28 carbon atoms. The hydrocarbyl or alkyl groups on the polynuclear aromatic material can be similarly selected. Suitable selection of hydrocarbyl chain length provides optimum solubility and compatibility properties.
The amount of the total additive composition (a) plus ~b) is an a~ount sufficisnt to cause a reduction of the - c~oud point of the paraffinic liquid to which it is added.
Often this amount is 50 to 2000 parts per million, pr2fera~
bly 100 to 600 parts per million (i.e. 0.01 to 0.6 percent by weight of the compositîon).
15Components (a) and (b) can also be used in the form of a concentrate in a diluent oil or other suitable medium.
When this is the case the absolute amounts of the individu~
al component will be much higher than their concentration in the final composition. Typically a concentrate will contain up to 50~ or more by weight of a diluent oil.
Calculation of the appropriate concentrations of active ingredients in a concentrate ~or any given application iæ
well within the abilities of those skilled in the art.
Other customary additives can also be present in the aompositions o~ the present invention. When the composi-tion is used as a fuel or a lubricant it can contain such materials as octane improvers, cetane improvers, antioxi~
dants such as 2,6-di-tertiary-butyl-4-methylphenol, rust 'inhibitors such as alkylated succinic acids and anhydrides, bacteriostatic agents, gum inhibitors, metal deactivators, and dispersants such as esters o~ a mono- or polyol and a high molecular weight mono-or polycarboxylic acid acylatin~
agent, especially those containing at least 30 carbon atoms in the acyl moiety. Other additives which can be pr~sent include detergents, antiweaF agents, -extreme pFessure ~ 213~136 agents, emulsifier~, demulsifier~, friction modifiers, and dyes.
Although the compositions of the present invention have been discussed and described principally as cloud point depressant, they are also themselves effective as pour point depressants. Thus the addition of an effective amount of the combination of components (a) and (b) will not only reduce the cloud point of a paraffinic liquid, but will normally also reduce the pour point. This further increases the utility of the present compositions, since they can be used not only to inhibit the onset of paraffin crystal formation, but also to retard the general solidifi~
cation of the liquid.
It is preferred, however, that, along with the combi~
nation of components (a) and ~b) and any optional customary ingredients, there is also present an effective amount of an (add~itional) polymeric pour point depressant. The ombination of the present additives with certain supple~
mental pour point depressants exhibit especially superior ~ properties of pour Point reduction. Materials which are use~ul as pour point depressants are well known and include such materials as alkyl acrylate polymers, alkyl methacry-late~polymers, esters of olefin-maleic anhydride polymers (including esters of ethylene/maleic anhydride copolymers 25~ ~and styrene/maleic anhydride copolymers), and in particular ethylene vinyl~acetate (E~A) copolymers.
VA aopolymers are well known materials, typically made by free-radial polymerization of vinyl acetate and thylene, op~ionally with other comonomers. Pre~erred ~;~;materials~ for use in the present invention are bina ~
copolymers which contain lS to 40 weight percent, and more pre~erably 33 to 38 weight percent copol~merized vinyl acetate. The number average molecular weight o~ the supplemental polymeric pour point depressant is not partic-~S ularly cri~ical but ~or EVA copolymers i preferably lO00to lO,OOO,;more pre~eràoly~l500 to 2600.
~`1~

~` 2135~36 ;
...

The desirable amount of the supplemental polymeric pour point depressant is that amount which will produce the desired reduction in pour point and will vary with the chemical nature of the polymer and of the paraffinic liquid in which it is to be employed. Effective amounts are typi-cally 0.1 to 10 times the amount of the total of components (a) and 5b), and preferably 005 to 2 times the amount. In a more absolute sense the amount of the supplemental polymeric pour point depressant typically comprises 100 to 2000 parts per million by weight of the final composition, preferably 200 to 400 parts per million. This supplemental material can also be present in a concentrate along with components (a) and (b) and other additives, if any; if this i5 the case the absolute amount of the material will be adjusted accordingly.
Each of the materials used in the present invention may be available as the pure chemical or may be present as a concentrate with a diluent such as miner~l oil. The choice of ~orm of the constituent materials is generally irrelevant to the present invention, so long as the amoun~
; ~ of diluent i5 taken into consideration in selecting the amount of activ agent employed.
As used herein, the term "hydrocarbyl substituent" or "hyd~ocarbyl group!' is used in its ordinary sense, which is 25 ~ well-known to those skilled in the art. Specifically, it refers to a group having a carbon atom directly attached to the remainder of the molecule and having predominantly hydrocarbon characterO Such groups include hydrocarbon 'groups, substituted hydrocarbon groùps, and hetero groups, 30 that is, groups which, while primarily hydrocarbon in character, contain atoms other than carbon present in a chain or ring otherwise composed of carbon atoms.
EXAMPLES
Examples 1-10. Compositions are prepared of a stan~
dard diesel fuel (Amoco~ Whi~ing base ~uel) containing various amounts o~ the composition of the present invention .,. :
- ., ~ - 213~136 , ,,~ , and, for comparison, no additive. The additive repre6enta~
tive of the present invention ii5 a mixture of a C12l4 fuma~
rate/vinyl acetate/ethyl vinyl ether copolymer (5.5% vinyl acetate moiety content and 3.1% ethyl vinyl ether content, by weight, weight average molecular weight about 20,000) and an alkylated naphthalene, in the parts by weight indicated. The alkylated naphthalene is substituted by a mi~ture of alkyI and alkylene groups and is prepared by alkylation of 1 part of naphthalene first with 1.9 parts by weight of a chlorinated ~hydrocarbon mixture having on average about 24 carbon atoms per molecule_ and having on average about 2 chIorine atoms per hydrocarbon chain, and thereafter with 7.4 parts by weight of a mixture of C16-Cl8 olefins, using 0.2 parts by weight AlCl3 catalyst. S~me of the li ted co~ponents are available as concentrates con~
taining a certain amount (up to 37~) of diluent oil. The compositions are reported:in Table I on an active chemical :~~ basis ~i.e. excluding the diluent oiI) and are tested by : the~ procedure of ASTM D 2500 "Cloud point o~ petroleum oils." Results of the test are reported to the nearest :3C, the temperature reported being the lowest temperature ;at which the sample is clear; at a temperature 3~ colder, cry6tal for6at10n is observed~

, ~, . .~ - ., -``~` 213~136 -TABLE I
¦EX. Fumarate Alkylated Cloud copolymer naphtha- point, :.- . .--ppm lene, ppm C ~ `
- - o -12, ~:
_ ~ _ _ ". ,"~, 3 76 : 180 -18 4 lO1 240 -18 ~ 18~ 450 _-18 lQ 7 252 600 -18 _ 97 96 18 9 19~ ~ 92 1-18 _ ~ ~
10 1630 1500 1_15 :-: .- :' . .
Examples 11-28. Examples l-10 are substantially ~1-~; ~ repeated in a diesel fuel from Star Enterprise. The -~
; : aoncentrations and results are shown in Table II~

:: : :; ~-, . ~ :

,: ~ - , , ,::
: :

21 3 ~ 1 3 6 ,, ,-, :, 16 ::
" ":, TABLE II ~ :~
Fumarate alkylated Cloud l ; ~;
copolymer naphtha- point, ppm lene, ppm C :~
= ~ -- ., "' :,'~
11 O ~f o6 ,'~';''"' ~
_ . ~,~-: ~ ~,,,."'.,' 12 630 1000 _9 . --_ , , ''~
13 630 1000 _9 ~ -~ 756 1000 _9 -_ , .. _ _ .
882 1000 _9 :- -16 1008 ~ 1000 _9 . ;
= ~_ ''~"'~'''' :"' '''"''' : 17 630 :~ 800 _9 ~ 10 18 630 600 _9 _ _ . ~, , . . _ _ ,`, ~ f, ~
: : l9 194 192 -6 ~ `;
: : 20 388 385 _9 -;;.
: 21 582 577 : : -6 ~
: _ _ . ~
22 776 ~ ~ 769 _ _ . . , ~.... "~, 23 970 9~2 _9 -~
: ~ ~ _ _ : : ~,.,~
24 1164 : 115~ ; -3 _ . ,~
~: 25 1552 1538 _9 .
, .: ! ' f ~ 26 1940 ~ 1923 ~ ~ _g j j j f . ~
, __ _ _ ~' " '" ~ ' ' ': ',-: ,:-, -27 252 600 ~ _9 -,.~
~ - _ . . ~-,.",~:, ~
20 : 28 126 300 _9 : _ -- - ._ ','~
: :
xample 29. The above procedure is repeated in a i~
diesel fuel dP~ignated DDR-490, Which has a cloud point o~
-6C. ~a) Addition o~ 386 to 773 ppm of the additive :~ ~
=~

~ 2~3~:136 combination of Example 8 reduces the cloud poi.nt to -9C.
(b) Addition of 213 to 639 ppm of the additive combination of Example 2 does not lead to a measurable change in cloud point at a measurement interval of 3C. More precis~
measurements, made u~ing an interval of less than 3C or using a differential scanning calorimetry method, will detect the reduction in cloud point.
Examles 30-33. The oil of Example 1 is treated with the following materials, defined as for Example 2, and the cloud point is determined:
TABIE III _ . .
Ex.Fumarate Alkylated . ..
copolymer, naphthalene, ::

321800 ~ 200 ~ :
33200 19~0 Example 34. Example 33 is repeated except that the alkylated naphthalene is replaced in turn by a correspond~
ing amount of the following ~aterials~
a. naphthalene, mono- and di-alkylated by a .
mixture of C-12 alkyl groups and C-22 to C-30 alkyl and alkylene groups.
j b. naphthalene, predominantly~monoalkylated by a mixture of C-~0 and C-30 alkyl groups.
c. l-nonylanthracene, reacted with chlorinated ~ .
C-24 paraffin wax.
Exam~e 35. Example 33 is repeated except that the fumarate copolymer:is replaced in turn by a corre~ponding -amount of khe ~ollowing materials~
a. a C12 14 alkyl fumarate/vinyl acetate/ethyl vinyl ether/ethylene tetrapolymer (5.5% vinyl acetate ,~ , ..;
18 ~ -moiety content, 3.1~ ethyl vinyl ether content, and 2%
~thylene muiety content, by weight), weight average molecu-lar weight about 4000.
b. a polymer of (di-(C12 to C1~ alkyl)) fumarate, n-butyl acrylate, and propyl vinyl ether, in relative weight percentages of 96.5%, 1.5%, and 2%, weight average ~ .:
~olecular weight 8,000.
c. methyl acrylate/vinyl acetate/ethyl vinyl etherjdi(Cl6 to C18 alkyl~fumarate tetrapolymer, having about 10 percent by weight copolymerized methyl acrylate, 2 percent by weight vinyl acetate, and l pe~cent by weight ethyl vinyl ether, weight average molecular weight 60,000.
In a separate example, this additive composition is added -.;;~
to a middle disti~late of predominantly C-14 - C-20 hydro~
carbons.
Example 36. A composition is prepared of 60 parts of the alkylated naphthalene and 40 parts of the alkyl fuma~
rate/vinyl acetate/ethyl vinyl ether copolymer of claim ~
To the diesel oil of ExampIe 1 is added a total of 213 parts psr million o~ the above alkylated naphtha-lene/fu~arate composition and 125 parts per million of an e~hylene vinyl acetate copolymer (33.5 weight percent vinyl acetate monomer, number average molecular weight 1900 2500).
Example 37. Example 36 is repeated except that the amount of the alkylated naphthalene/fumarate composition is - -426 parts per mlllion and the amount of the EVA copolymer is 250 parts per million.
~; Each of the documents referred to above is incorps ;~
rated herein by reference. Except in the Examples, or where otherwise explicitly indicated, all numerical quanti~
ties in this description specifying amounts of materials, reaction conditions, molecular weights, number of carbon atoms, and the like, are to be understood as modified by ` ~-the word "about." Unless otherwise indicated, each chemi~
cal or composition referred to herein should be interpreted .
-, ~i 2135~36 as being a commercial grade material which may contain the isomers, by-products, derivatives, and other such materials which are normally understood to be present in the commer-cial grade. However, the amount of each chemical component is presented exclusive of any so}vent or diluent oil which may be customarily present in the commercial material, unless otherwise indicated. As used herein, the expression "consisting essentially of" permits the inclusion of substances which do not materially affect the basic and novel characteristics of the composition under consider-ation.

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Claims

1. A composition comprising:
(a) a polymer of:
(i) a hydrocarbyl ester of an ethylenically unsaturated acid of 3 to 6 carbon atoms, wherein the hydro-carbyl group contains about 8 to about 40 carbon atoms, (ii) an ester-containing monomer selected from the group consisting of alkyl esters of ethylenically unsaturated acids of 3 to 6 carbon atoms wherein the alkyl group contains fewer than 8 carbon atoms and vinyl alkano-ates wherein the alkanoate group contains up to about 8 carbon atoms, and (iii) an alkyl ether monomer wherein the alkyl group contains up to about 8 carbon atoms; and (b) a polynuclear aromatic material, substituted on at least one ring with at least one hydrocarbyl group having about 8 to about 20 carbon atoms and with at least one hydrocarbyl group having about 21 to about 40 carbon atoms, wherein the amounts of components (a) and (b) are such that the composition, when added to a paraffinic liquid, provides a reduction in the cloud point thereof.

2. The composition of claim 1 wherein the polymer of (a) comprises about 1 to about 15 percent by weight of the ester-containing monomer (ii) and about 1 to about 15 percent by weight of the alkyl ether monomer (iii).

3. The composition of claim 2 wherein the ester-containing monomer (ii) and the alkyl ether monomer (iii) are present in relative molar amounts of 9:1 to 1:9.

4. The composition of claim 1 wherein the polymer is a polymer of a dialkyl fumarate or a dialkyl maleate, a vinyl alkanoate, and an alkyl vinyl ether.

5. The composition of claim 4 wherein the alkyl groups of the dialkyl fumarate or dialkyl maleate contain about 10 to about 16 carbon atoms.

.. . .

6. The composition of claim 4 wherein the alkyl groups of the dialkyl fumarate or dialkyl maleate contain about 12 to about 20 carbon atoms.

7. The composition of claim 4 wherein the alkyl groups of the dialkyl fumarate or dialkyl maleate contain about 18 to about 28 carbon atoms.

8. The composition of claim 4 wherein the copolymer is a copolymer of the dialkyl fumarate or the dialkyl maleate with vinyl acetate and ethyl vinyl ether.

9. The composition of claim 1 wherein the polymer has a number average molecular weight of about 3,000 to about 300,000.

10. The composition of claim 9 wherein the polymer has a number average molecular weight of about 5,000 to about 100,000.

11. The composition of claim 1 wherein the weight ratio of the hydrocarbyl groups in (b) of about 8 to about 20 carbon atoms to the hydrocarbyl groups of about 21 to about 40 carbon atoms is about 10:1 to about 1:1.

12. The composition of claim 1 wherein the polynuclear aromatic hydrocarbon is naphthalene.

13. The composition of claim 12 wherein the naphtha-lene is substituted by a mixture of alkyl and alkylene groups, in part about 16 to about 18 carbon atoms and in part about 22 to about 26 carbon atoms in length.

14. The composition of claim 12 wherein the substitu-tion on the naphthalene component comprises at least in part alkylene groups of at least about 14 carbons atoms, which alkylene groups link at least a portion of the naphthalene moieties into a polymeric structure.

15. The composition of claim 1 wherein components (a) and (b) are present in relative amounts of about 90:10 to about 5:95 by weight.

16. The composition of claim 15 wherein the relative amounts of components (a) and (b) are about 80:20 to about 10:90.

17. The composition of claim 16 wherein the relative amounts of components (a) and (b) are about 50:50 to about 20:80.

18. The composition of claim 1 further comprising a concentrate-forming amount of an organic hydrocarbon liquid.

19. A composition of a paraffinic liquid and an amount of the composition of claim 1 sufficient to reduce the cloud point of said paraffinic liquid.

20. The composition of claim 19 wherein the total amount of (a) and (b) is about 50 to about 2000 parts per million.

21. The composition of claim 20 wherein the total amount of (a) and (b) is about 100 to about 600 parts per million.

22. The composition of claim 19 wherein the paraffin-ic liquid is a middle distillate.

23. The composition of claim 1 further comprising a pour point depressant in an amount sufficient to reduce the pour point of a paraffinic liquid.

24. The composition of claim 23 wherein the pour point depressant is an ethylene/vinyl acetate copolymer.

25. The composition of claim 19 further comprising an amount of an ethylene/vinyl acetate copolymer sufficient to reduce the pour point of the composition.

26. The composition of claim 25 wherein the pour point depressant is an ethylene/vinyl acetate copolymer.

27. A process for reducing the cloud point of a paraffinic liquids, comprising adding thereto an effective amount of a combination of:
(a) a polymer of (i) a hydrocarbyl ester of an ethyl-enically unsaturated acid of 3 to 6 carbon atoms, wherein the hydrocarbyl group contains about 8 to about 40 carbon atoms, (ii) ester-containing monomers selected from the group consisting of alkyl esters of ethylenically unsatu-rated acids of 3 to 6 carbon atoms wherein the alkyl group contains fewer than 8 carbon atoms and vinyl alkanoates wherein the alkanoate group contains up to about 8 carbon atoms, and (iii) alkyl ether monomers wherein the alkyl group contains up to about 8 carbon atoms; and (b) a polynuclear aromatic material, substituted on at least one ring with at least one hydrocarbyl group having about 8 to about 20 carbon atoms and with at least one hydrocarbyl group having about 22 to about 40 carbon atoms.