Comb polymers

The present invention relates to comb polymers KP, produced from macromonomers of formula (I) ##STR1## where X represents a group which comes from the initiator system, preferably an alkyl group with 1-50 C atoms; R1 represents an alkyl group with 1-18 C atoms, preferably 1-10 C atoms, particularly preferably 1-4 C atoms; R2 and R3 each represent an alkyl group with 1-8 C atoms; and B represents a terminal alkene group with at least 2 and not more than 12 C atoms; wherewith the compound of formula (I) is converted, by means which are per se known, to a compound of formula (II) which contains an active hydrogen substituent in the terminal position: ##STR2## where X, R1, R2, a, b, and c are as defined above, and a represents the group B modified by introduction of the active hydrogen function; wherewith the compound of formula (II) in turn is acylated to a macromonomer of formula (IV) by a reagent MR which introduces the (meth)acryloyl group: ##STR3## where X, R1, R2, R3, A, a, b, and c are as defined above, and R4 represents hydrogen or methyl; and the macromonomers of formula (IV) thus obtained are converted to the comb polymers KP by radical polymerization with monomers M chosen from the group comprised of: (meth)acrylic acids of C.sub.1 -C.sub.28 -alkanols, functionalized radically polymerizable monomers, vinyl esters of fatty acids and vinylaromatic monomers.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The invention relates to comb polymers and a method of manufacturing same 
from macromonomers having a terminal double bond. 
2. Discussion of the Prior Art 
In the prior art, anionic oligomerization is recommended for synthesizing 
functional oligomers, particularly telechic oligomers with a narrow 
molecular weight distribution. In particular, with respect to monomers 
such as styrene, 1,3-butadiene, and isoprene, the literature describes 
manufacture of alpha,omega-bifunctional oligomers by initiation with 
bifunctional initiators and termination with suitable reagents. 
Macromonomers are suitable for a number of interesting applications, such 
as use as starting materials for the manufacture of comb polymers. (See 
Houben and Weyl, "Methoden der Organischen Chemie", 4th Ed., Vol. E20, 
pub. Georg Thieme, pp. 647-648, 1166-1167 (1987); Rempp, P. F., and 
Franta, E., Adv. Polym. Sci., 58, 1-3 (1984); and Mark, H. F., et al., 
"Encyclopedia of polymer science and technology", Vol. 9, pub. J. Wiley, 
pp. 195-204 (1987)). The unpublished Eur. Pat. App. 94-105,648.3 discloses 
the manufacture of comb polymers by radical copolymerization of 
olefin-copolymer macromonomers of formula 
##STR4## 
where R' represents hydrogen or methyl; 
R represents the organic group in an organolithium compound; 
[A] represents a segment formed by 1,4-addition of butadiene, optionally 
substituted with an alkyl group with 1-6 C atoms; 
[A'] represents a segment formed by vinyl addition of butadiene, optionally 
substituted with an alkyl group with 1-6 C atoms; and 
n and m each represent an integer from 10 to 3000; with 
(meth)acrylic acid esters of C.sub.1 -C.sub.26 -alkanols. 
wherein, R is contributed from the organolithium catalyst used in the 
anionic polymerization. Preferably R is a butyl or phenyl group. 
Comb polymers comprised of a polyalkyl (meth)acrylate main chain and high 
molecular weight hydrocarbon side chains have extraordinary behavior in 
solutions, in addition to other technically interesting properties. The 
properties of such comb polymers suit them for use as viscosity index 
improving agents (V.I.-improvers) in the lubricants sector, as described, 
e.g., in the above-cited Eur. Pat. App. 94-105,648.3. (See Ullmann's 
Encyclopedia of Industrial Chemistry, 5th Ed., Vol. A 15, pub. VCH, pp. 
448-449 (1990)). 
The macromonomers used according to the cited Eur. Pat. App. as starting 
materials for the comb polymers are produced on the basis of dienes. This 
route of synthesis comprises a hydrogenation step in addition to the 
polymerization and functionalization. It would be preferable to use a 
direct method of manufacturing saturated olefinic polymers having a 
reactive terminal group. Devising such a method is the underlying problem 
of the invention. In solving the problem, one advantageously exploits 
catalysis with metallocene catalysts (see Muehlhaupt, R., Nachrichten aus 
Chemie und Technik, 41, 1341 (1993)). 
DESCRIPTION OF THE INVENTION 
Accordingly, the invention relates to comb polymers KP produced from 
macromonomers of formula (I): 
##STR5## 
where 
X represents a group contributed from the initiator system, and which is 
preferably an alkyl group with 1-50 C atoms; 
R.sub.1 represents an alkyl group with 1-18 C atoms, preferably 1-10 C 
atoms, particularly preferably 1-4 C atoms; 
R.sub.2 and R.sub.3 each represent an alkyl group with 1-8 C atoms; and 
B represents a terminal alkene group with at least 2 and not more than 12 C 
atoms, which group is preferably chosen from the group comprising: 
##STR6## 
with the following provisions: (1) If the parameter c represents a molar 
percentage of greater than 0 mol %, the parameter a represents a molar 
percentage of zero mol %, of the monomers in the macromonomer of formula 
(I); 
(2) The sum of the parameters (a+b) equals 100 mol % of the monomers in the 
macromonomer of formula (I), wherewith a should be at most 80 mol %, or 
(3) The sum of b and c should equal 100 mol % of the monomers in the 
macromonomer of formula (I); and 
(4) If a is zero, R1 becomes R1', which represents an alkyl group with 
2-18, preferably 2-10, particularly preferably 2-4 C atoms; 
wherewith the compound of formula (I) is converted, by means which are per 
se known, to a compound of formula (II) which contains an active hydrogen 
substituent in the terminal position: 
##STR7## 
where 
X, R1, R2, R3, a, b, and c are as defined above, and 
A represents the group B modified by introduction of the active hydrogen 
function; 
wherewith the compound of formula (II) in turn is acylated to a 
macromonomer of formula (IV) by a reagent MR which introduces the 
(meth)acryloyl group: 
##STR8## 
where 
X, R1, R2, R3, A, a, b, and c are as defined above, and 
R4 represents hydrogen or methyl; and the macromonomers of formula (IV) 
thus obtained are converted to the comb polymer KP by radical 
polymerization with monomers M selected from the group consisting of: 
(meth)acrylic acids of C.sub.1 -C.sub.28 -alkanols, 
functionalized, radically polymerizable monomers, 
vinyl esters of fatty acids, and 
vinylaromatic monomers. 
The macromonomers of formula (I) are saturated except for the terminal 
unsaturation. 
DETAILED DESCRIPTION OF THE INVENTION 
The invention particularly relates to comb polymers KP manufactured 
starting with the macromonomers of formula (I), which macromonomers are 
reacted with a hydroxyl-group-transferring reagent of formula (III) 
EQU Q--R--OH (III) 
where 
Q represents a function which adds to the double bond in B in formula (I), 
and 
R represents an inert organic group with 2-16 C atoms; 
resulting in compounds of formula (II-A) 
##STR9## 
where 
X, R1, R2, R3, a, b, and c are as defined above, and 
--B'--Q'-- represents the moiety formed by addition of Q to B across the 
double bond; 
and the compounds of formula (II-A) are acylated to macromonomers of 
formula (IV-A) by a reagent MR which introduces the (meth)acryloyl group: 
##STR10## 
where 
X, R1, R2, R3, R4, a, b, c, B', Q', and R are as defined above; 
and, further, the macromonomers of formula (IV) thus obtained are converted 
to the comb polymers KP by radical polymerization with monomers M selected 
from the group consisting of: 
(meth)acrylic acids of C.sub.1 -C.sub.28 -alkanols, 
functionalized monomers, 
vinyl esters of fatty acids, and 
vinylaromatic monomers, such as styrene and C.sub.1 -C.sub.4 
-alkylstyrenes. 
In general, the weight ratio of macromonomer IV to monomer M is in the 
range 2:98 to 100:0. As a rule the proportion of (meth)acrylic acid esters 
in the monomer M is in the range 60-100 wt. %, preferably 75-100 wt. %, 
particularly preferably 95-100 wt. %. 
Preferably the monomers M are selected from the group comprised of: 
(meth)acrylic acid derivatives of formula (V) 
##STR11## 
where 
R4' represents hydrogen or methyl, 
R5 represents an alkyl group with 1-24 catoms, particularly 4-24 C atoms, 
and 
Z represents oxygen or a group NR7 where 
R7 represents hydrogen or an alkyl group with 1-6 C atoms; 
functionalized monomers of formula (VI) in the amount of 0-75 wt. %, 
preferably 0.5-50 wt. %, particularly preferably 2-15 wt. %, based on the 
total weight of the monomers M 
##STR12## 
where 
R4" represents hydrogen or methyl, and 
Bs represents an (inert) heterocyclic 5- or 6-membered ring or a group 
##STR13## 
where 
Z' represents oxygen or a group --NR7', and 
V represents a hydrocarbon bridge, optionally alkylated, having a total of 
2-50 C atoms which may be interrupted by oxygen bridges, the number of 
which 0-bridges is preferably in the range 
EQU 2 to (q-1), 
where 
q is the number of C-bridge atoms in the chain, and 
R6 represents --OR7' or --NR8R9, 
where 
R7' and R7" represent 
hydrogen or 
an alkyl group with 1-24 C-atoms, preferably 8-22 C atoms or 
alkyl-substituted alkyl groups, preferably phenyl groups having C.sub.1 
-C.sub.18 -alkyl substituents, particularly preferably phenyl groups 
having C.sub.6 -C.sub.16 -alkyl substituents, where R8 and R9 each 
independently represent an alkyl group with 1-6 C atoms, or together with 
the nitrogen atom and possibly other hetero atoms represent a 5- or 
6-membered heterocyclic ring; 
wherewith, preferably, 
R7' represents hydrogen or an alkyl group with 1-6 C atoms; 
vinyl esters of formula (VII), in the amount of preferably 0-80 wt. %, 
particularly preferably 5-20 wt. %, of the total weight of the monomers M 
##STR14## 
where R10 represents an alkyl group, optionally branched, with 1-13 C 
atoms; and 
vinylaromatics of formula (VIII), in the amount of preferably 0-60 wt. %, 
particularly preferably 0.5-40 wt. %, of the total weight of the monomers 
M 
##STR15## 
where R11 and R12 represent hydrogen or an alkyl group with 1-4 C atoms. 
As a rule, the weight-percentages of the monomer components M add up to 100 
wt. %. All of these monomers may be known. For certain applications, 
nitrogen-free comb polymers are preferred. 
In addition to (meth)acrylic acid esters of formula (V) having 1-6 C atoms 
(particularly in the form of mixtures of such esters), compounds of 
formula (V) may be used in which R5 has 6-24 C atoms; wherewith such 
compounds of formula (V) are present in amounts of 40-100, preferably 
80-100 parts by weight, based on the total weight of the monomers of 
formula (V). Here the alkyl groups of R5, represent an alkyl in the range 
9-20 C atoms, more particularly 10-18 C atoms, with degrees of branching 
ranging from 25-80% or more, and may be contributed from products of, 
e.g., large scale manufacturing processes such as the oxo process. 
Suitable materials of formula (V) are, e.g., the commercial product 
Lincol.RTM. of the firm Condea, esters of Dobanol.RTM. alcohols (Shell), 
esters of Alfol.RTM. alcohols (Condea), esters of Lorol.RTM. alcohols, 
esters of tallow fat alcohols, etc. Of particular interest are, e.g., 
esters of alcohol mixtures of isomeric isodecyl alcohols, esters of 
alcohol mixtures of isomeric isoundecyl alcohols, or esters of a mixture 
of alcohols with an average 13.2-13.8 C atoms, principally comprised of 
alcohols with 12-15 C atoms (Dobanol.RTM. 25 L). Other good candidates are 
esters of cyclic alkanols, e.g. having 5-8 ring carbon atoms, e.g. 
cyclopentanol, cyclohexanol, cyclooctanol, benzyl alcohol, and 
alkyl-substituted cyclohexanols such as 4-tert-butylcyclohexanol. 
Representative examples are methyl (meth)acrylate, ethyl (meth)acrylate, 
butyl (meth)acrylate, ethylhexyl (meth)acrylate, octyl (meth)acrylate, 
dodecyl (meth)acrylate, hexadecyl (meth)acrylate, eicosyl (meth)acrylate; 
and compounds of formula (V) where Z represents NR7, e.g. 
(meth)acrylamide, N-methyl (meth)acrylamide, N,N-dimethyl 
(meth)acrylamide, and N-t-butyl (meth)acrylamide. Copolymers may be formed 
with, e.g., 
monomers of formula (VI) such as methyl methacrylate, 2-dimethylaminoethyl 
methacrylate, or butyl acrylate, as monomers M, and 
2-(4-morpholinyl)ethyl methacrylate or N-dimethylaminopropyl 
methacrylamide, as monomers of formula (VI). 
In certain proportions, e.g. up to 20 parts by weight, based on the total 
weight of the monomers of formula (V), R5 may also be replaced with an 
aromatic or cyclic group, particularly a phenyl, naphthyl, or benzyl 
group, which group may be substituted with, e.g., an alkyl group having 
1-4 C atoms, or fluorine, or a group analogous to R6. 
Representative examples are phenyl (meth)acrylate, 1-phenylethyl 
(meth)acrylate, benzyl (meth)acrylate, N-phenyl (meth)acrylamide, N-benzyl 
(meth)acrylamide, 4-hydroxyphenyl (meth)acrylate, naphthyl (meth)acrylate, 
9-fluorenyl (meth)acrylate, and pentafluorophenyl (meth)acrylate. Examples 
of cycloalkyl (meth)acrylate compounds are: cyclopentyl-, cyclohexyl-, and 
cyclooctyl (meth)acrylate; 3,3,5-trimethylcyclohexyl (meth)acrylate, 
3-cyclohexylpropyl (meth)acrylate, N-cyclohexyl (meth)acrylamide, 
4-hydroxycyclohexyl (meth)acrylate, and 4-fluorocyclohexyl (meth)acrylate. 
Examples of monomers of formula (VI) are heterocyclic vinyl compounds, 
particularly vinyl lactams, vinylimidazoles, vinylpyridines, and 
vinylcarbazoles (see Ger. OS 26 34 033). A preferred Example is 
N-vinyl-2-pyrrolidone. 
Particular heteroatoms which may be present in the monomers of formula (VI) 
are nitrogen, oxygen, and sulfur. Particularly important compounds of 
formula (VI) are functionalized (meth)acrylate esters and 
(meth)acrylamides, particularly those having at least one ether bridge, 
and preferably being of a relatively high degree of alkoxylation. 
Examples of compounds of this type are, e.g., (meth)acrylic acid esters of 
alkoxylated aliphatic alcohols, e.g. alkoxylated butanol, and other 
alkoxylated alcohols, with candidates for the underlying alcohols being, 
among others: 
methanol, ethanol, propanol, pentanol, and isomers thereof, hexanol, and 
isomers thereof, cyclohexanol, methylcyclohexanol, 2-ethylhexanol, and 
higher aliphatic monohydric alcohols, such as isodecyl alcohol, isoundecyl 
alcohol, isotridecyl alcohol, fatty alcohols produced from natural raw 
materials, etc. 
Other candidates are: 
alkoxylated phenols, e.g. based on phenol, alkyl-substituted phenols (e.g. 
tert-butylphenol and 2,6-dimethylphenol), isomeric mixtures and technical 
alkylphenols (comprising, e.g., octylphenol, nonylphenol, and/or 
dinonylphenol), 
naphthol, and alkyl-substituted naphthols. 
Further, addition products of ethylene oxide or propylene oxide to 
substituted alcohols, e.g.: furfurol, tetrahydrofurfurol, 
2-methoxybutanol, 2-dimethylaminoethanol, 1-dimethylamino-2-propanol, 
3-dimethylamino-1-propanol, 2-morpholinoethanol, 2-(2-pyridyl)ethanol, 
N-(2-hydroxyethyl)piperidine, and N-(2-hydroxyethyl)pyrrolidone. 
Of special interest are alcohols which represent (statistical) addition 
products of ethylene oxide and propylene oxide to an alcohol such as, 
e.g., butanol. A preferred Example is (meth)acrylic acid esters of 
ethoxylated fatty alcohol mixtures, e.g. esters of C.sub.16 -C.sub.18 
-fatty alcohol mixtures with degrees of ethoxylation in the range 11-50. 
A suggested molecular weight range for the preferred monomers with a high 
degree of alkoxylation is, e.g., the range up to about 2000 Dalton. 
However, this is not a limitation. Depending on the degree of alkoxylation 
and the size of the group R2, higher molecular weights up to about 5000 
Dalton may be used. The monomers of formula (V) may be present as 
mixtures, comprised of methacrylates of various of the above-described 
alkoxylated alcohols. 
Also of interest are 
alkyl esters, substituted with at least one hydroxyl group, having 2-50 C 
atoms in the alkyl group, e.g., 2-hydroxyethyl (meth)acrylate, 2- and 
3-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, or 
amides such as N-(2-hydroxyethyl)methacrylamide and 
N-(3-hydroxy-2,2-dimethylpropyl)methacrylamide. 
Further, 
(meth)acrylic acid esters of amino alcohols, such as diethylaminoethyl 
(meth)acrylate, 2-(dimethylamino)propyl (meth)acrylate, 
3-dimethylamino-2,2-dimethylpropyl (meth)acrylate, 2-tert-butylaminoethyl 
(meth)acrylate, 2(dimethylamino)ethoxyethyl (meth)acrylate, and 
corresponding amides, such as N-dimethylaminomethyl (meth)acrylamide, 
N-(3-dimethylamino)propyl (meth)acrylamide, N-(1-piperidinyl)methyl 
(meth)acrylamide, N-(3-morpholinylpropyl) (meth)acrylamide, 
2-(1-imidazolyl)ethyl (meth)acrylate, N-methacryloyl-2-pyrrolidone, etc. 
Particularly interesting candidates as monomers of formula (VII) are vinyl 
acetate and vinyl propanoate. 
Monomers of formula (VIII) which might be particularly mentioned are 
styrene, .alpha.-methylstyrene, and p-methylstyrene. 
The preparation of the macromonomers of formula (I) from the 
hydroxyl-group-containing compounds of formula (II) by means of a reagent 
MR which transfers (meth)acryloyl groups proceeds analogously to known 
acylations. Thus, e.g., MR may be a (meth)acrylic acid anhydride, or a 
(meth)acrylic acid halide, or particularly the chloride. However, it is 
preferred to carry out the acylation by transesterification with 
(meth)acrylic acid esters of lower alcohols, e.g. the alcohols with 1-4 C 
atoms, with the preferred such ester being methyl (meth)acrylate. The 
transesterification may be acid- or base-catalyzed. It has been found to 
be advantageous, e.g., to carry out the transesterification with 
orthotitanates, e.g. isopropyl titanate, in the suggested amounts of 0.1-1 
wt. %, based on the weight of the alcohol, at elevated temperature, e.g. 
at the boiling point of the lower (meth)acrylic acid ester which ester 
also serves as a solvent (see U.S. Pat. No. 5,254,632). 
Of technical interest also is transesterification using a combination of a 
lithium compound, e.g. lithium hydroxide, and calcium oxide. 
In all cases it is recommended that polymerization inhibitors be used, e.g. 
sterically hindered phenols such as 4-methyl-2,6-di-tert-butylphenol (see 
Ullmann's Encyclopedia of Industrial Chemistry, 5th Ed., Vol. A 20, pub. 
VCH, pp. 461-475 (1992)). 
The transesterification may also be carried out with free (meth)acrylic 
acid by the DCC (dicyclohexylcarbodiimide) method, particularly if the 
terminal group B'--Q'--ROH in formula (II-A) is produced by the addition 
of maleic anhydride with subsequent imidification with an alkanolamine. 
(For methods, see Guanon, Y., and Rempp, P., Makrom, Chem., 188, 2111-2119 
(1987)). Various methods may be used to produce the hydroxyl-group 
containing compounds of formulas (II) and (II-A) from the macromonomer of 
formula (I). Of particular interest is direct production by 
hydroformylation. E.g., one may employ the reaction with a reagent of 
formula (III) where Q represents a thiol group and B represents an alkyl 
group with 2-8 C atoms, particularly an alpha,omega-thioalcohol, e.g. 
thioethanol, thiopropanol, or thiobutanol. 
Another method of converting the compounds of formula (I) to the 
hydroxyl-group-containing compounds of formula (II) is to react the 
compound of formula (I) (ENE-reaction) with maleic anhydride, followed by 
imidization with an alpha,omega-aminoalcohol, e.g. ethanolamine. 
Advantageously, the method may be as follows: The compound of formula (I) 
is reacted, without solvent, with maleic anhydride, in a molar ratio of 
1:2.5, at about 200.degree. C., under nitrogen, with stirring, for about 
12 hr. Then, preferably excess maleic anhydride is distilled off under 
vacuum (about 20 mbar) at about 160.degree. C. 
Advantageously, the imidization of the maleic anhydride adduct with the 
alpha,omega-aminoalcohol, e.g. ethanolamine, is carried out in a molar 
ratio of 1:3, again without a solvent. The reaction mixture is thoroughly 
intermixed at about 100.degree. C., and is then heated for about 3 hr at 
160.degree. C., followed by distillation-off of the excess ethanolamine at 
160.degree. C. at &lt;5 mbar (for about 4 hr). Advantageously in this case a 
combination of (meth)acrylic acid and DCC is used (as reagent MR) for the 
acylation. Thus, for example, the esterification is carried out with the 
imidized maleic anhydride adduct, as a compound of formula (II-A), and the 
(meth)acrylic acid, in the presence of an organic base such as, e.g., 
4dimethylaminopyridine and dicyclohexylcarbodiimide, in a molar ratio of 
1:1.2:1.4:1.2, with addition of a polymerization inhibitor such as, e.g., 
200 ppm of 4-methyl-2,6-di-tertbutylphenol (10% in a suitable inert 
solvent such as, e.g., dichloromethane), over a relatively long duration, 
e.g. 72 hours. The dicyclohexylurea which is liberated should be as 
insoluble as possible in the solvent, so that it can be removed by 
filtration. The product may be refined, e.g., using column chromatography 
(e.g. a kieselgel 60 column, comprising silica gel). The number average 
molecular weight Mn of the macromonomers of formula (IV) is in the range 
500-50,000 g/mol, preferably 1,000-20,000 g/mol (determined by size 
exclusion chromatography (SEC) (see Ullmann's, loc.cit., Vol. A20, pp. 
520-533, (1992)). The inventive comb polymers can be produced by radical 
polymerization of the monomers M in the presence of the macromonomers of 
formula (IV) or (IV-A) (see Rauch-Puntigam, H. and Voelker, Th., "Acryl- 
und Methacrylverbindungen", pub. Springer-Verlag (1968)). 
Smaller reaction mixtures may be accommodated, e.g., in a Schlenk vessel. 
With larger reaction mixtures one uses a reactor with a stirrer, gas feed 
means, and heating means. The macromonomer of formula (IV) and the monomer 
M of formulas (V)-(VIII) are dissolved in a suitable inert solvent L, e.g. 
in toluene or xylene, in the amount of about 50 wt. %. In a typical 
reaction mixture these monomer components are present in a ratio of 1:1 by 
weight. Degassing is carried out by addition of dry ice, and purging with 
nitrogen for about 10 minutes. Advantageously, the reaction mixture is 
heated to approximately the polymerization temperature, e.g. 77.degree. 
C., and the initiator is added, e.g. in a 1% solution in the solvent L. 
Candidates for use as initiators are the known initiators, e.g., azo 
compounds such as azobisisobutyronitrile (AIBN), or peroxy-compounds, in 
the usual amounts, e.g. 0.1-1 wt. % (based on the weight of the monomers). 
Advantageously, additional initiator is post-added at certain intervals, 
e.g. after 4 hr and after 6 hr. The overall duration of the polymerization 
process is ordinarily on the order of 1 day. 
The comb polymer KP formed has a main chain essentially comprised of alkyl 
(meth)acrylate of formula (V) and side chains comprised of macromonomers 
of formula (IV). 
The macromonomers of formula (I) have been made available by virtue of 
various recent developments in the art. Particularly noteworthy is, e.g., 
the possibility of producing terminally unsaturated olefin-macromonomers 
by means of metallocene catalysis. Suitable starting compounds are, e.g., 
ethylene, propylene, or other .alpha.-olefins, and combinations thereof. 
Preferred is (referring to the above description of the invention) 
the variant of case (2) (case 2') wherein b is 100 mol % (see Muehlhaupt, 
R., Nachr. Chem. Techn. Lab. (pub. VCH), 41., (12):1241-1351(1993)), or 
the variant of case 3' wherein c is 100 mol %, preferably produced by 
cationic polymerization of isobutylene. 
As starting compounds one might mention, e.g., industrially produced 
macromonomers of the "reactive polyisobutylene" type, having reactive 
exo-double bonds. These macromonomers can be hydroformylated, to form, 
among other things, macroalcohols of formula (II). The molecular weights 
are preferably in the range 1000-5000. Also of interest are propene 
macromonomers with a terminal double bond; suggested number average 
molecular weights Mn are in the order of about 800-5000 g/mol. 
The inventive comb polymers are particularly suited for use in tribology, 
or as lubricating oil additives as viscosity index improvers with 
particularly desirable rheological properties, as dispersants of the 
"ashless" type, etc.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
Having generally described this invention, a further understanding can be 
obtained by reference to certain specific examples which are provided 
herein for purposes of illustration only and are not intended to be 
limiting unless otherwise specified. 
EXAMPLES 
In the Examples, macromonomers and comb polymers based on macroalcohols 
prepared from polyisobutylene (PIB) and atactic polypropylene (PP) are 
described. The effectiveness of comb polymers as dispersants is 
demonstrated in laboratory dispersion tests. The advantages of 
non-dispersant comb polymer viscosity index improvers (hereinafter, 
V.I.-improvers) in comparison to conventional linear PAMA V.I.-improvers 
are shown. The key benefit is an improved relation between thickening and 
shear stability. 
Materials Used 
The macroalcohols are products having primary OH groups; these products are 
prepared by hydroformylation and subsequent hydrogenation of terminally 
unsaturated PIB or PP. 
Table of materials: 
KEY to Table: 
(a) Name; 
(b) Molecular weight Mn (by vapor pressure osmosis); 
(c) Thickening action, KV100 test (ASTM D 445), at 10 wt. % in 
mineral-oil-based 150N measuring oil. 
(a) PIB-OH-I; (b) 2230; (c) 9.42 centistoke (cSt). (a) PIB-OH-II; (b) 2950; 
(c) 10.27 cSt. (a) PP-OH; (b) 1440; (c) 8.13 cSt. 
Additional Materials Used 
100N=100N-oil. 
Tempol=4-hydroxy-2,2,6,6-tetramethylpiperidinoxyl. 
HME=hydroquinone monomethyl ether. 
LiOMe=lithium methanolate. 
MMA=methyl methacrylate. 
DMA=i-decyl methacrylate. 
AMA-1=methacrylate of a mixture of C.sub.11 -C.sub.16 -alcohols. 
AMA-2=methacrylate of tallow fatty alcohols. 
BMA=butyl methacrylate. 
MEMA=2-N-morpholinoethyl methacrylate. 
VP=N-vinylpyrrolidone. 
S=styrene. 
IN-1=tert-butyl perpivalate. 
IN-2=tert-butyl per-2-ethylhexanoate. 
IN-3=tert-butyl per-isononanoate. 
Production of the Macromonomers by Transesterification of the Macroalcohols 
PIB-OH and PP-OH 
Example 1 
Production of the macromonomer PIB-MM-I (50% in 100N) 
Apparatus: 4-liter three-necked flask with an electrical heating mantle, 
sickle-shaped stirrer, internal thermometer, air inlet, and distillation 
head with packed column. 
900 g PIB-OH-I was dissolved in 900 g 100N-oil by stirring 12 hr at 
100.degree. C. After cooling, 1063 g MMA, 85 mg Tempol, and 350 mg HME 
were added. After heating to reflux while air was passed through the 
mixture, about 160 g MMA was distilled-off to effect azeotropic drying. 
After cooling to about 95.degree. C. and addition of 1.7 q LiOMe, the 
mixture was refluxed for 3 hours, following which 300 g MMA was distilled 
off along with a small amount of methanol. As a further refinement step, 
the excess MMA was removed in a rotary vacuum evaporator at 50.degree. C. 
and 1 mbar. 
Yield: 1800 g oil solution of the macromonomer PIB-MM-I. 
Example 2 
Production of the macromonomer PIB-MM-II (50% in 100N) 
The apparatus and procedure were analogous to Example 1, but 900 g of the 
macroalcohol PIB-OH-II was used instead of PIB-OH-I. 
Yield: 1800 g oil solution of the macromonomer PIB-MM-II. 
Example 3 
Production of the macromonomer PP-MM (50% in 100N) 
The apparatus and procedure were analogous to Example 1, but 900 g of the 
macroalcohol PP-OH was used. 
Yield: 1800 g oil solution of the macromonomer PP-MM. 
Production of Dispersant Comb Polymers 
Example 4 
Production of a dispersant comb polymer V.I.-improver KP-4 
Apparatus: 200-mL three-necked flask with oil heating bath, sickle-shaped 
stirrer, internal thermometer, and N.sub.2 pass-over. 
The following were charged to the vessel: 
13.2 g MEMA 
105.6 g PIB-MM-II 
1.2 g 100N 
After heating to 75.degree. C. under nitrogen, a mixture of 0.1 g IN-1 and 
0.1 g IN-2 was added and the temperature of the oil bath was adjusted to 
95.degree. C. An additional dose of 0.13 g IN-2 was added 4 hours 
following the first initiator addition, and again after another 2 hr. The 
temperature was maintained at 95.degree. C. for 6 hours after the last 
initiator dosing. 
Yield: 120 g 55% oil solution of the dispersant comb polymer KP-4. 
Example 5 
Production of a dispersant comb polymer V.I.-improver KP-5 
The following were charged to the apparatus of Example 4: 
9.9 g DMA 
3.3 g MEMA 
105.6 g PIB-MM-I 
1.2 g 100N 
After heating to 75.degree. C. under nitrogen, a mixture of 0.2 g IN-1 and 
0.2 g IN-3 was added and the temperature of the oil bath was adjusted to 
105.degree. C. An additional dose of 0.13 g IN-3 was added 4 hours 
following the first initiator addition. The temperature was maintained at 
105.degree. C. for 6 hours thereafter. 
Yield: 120 g 55% oil solution of the dispersant comb polymer KP-5. 
Example 6 
Production of a dispersant comb polymer V.I.-improver KP-6 
The following were charged to the apparatus of Example 4: 
9.9 gBMA 
3.3 g MEMA 
105.6 g PIB-MM-I 
1.2 g 100N 
The procedure was otherwise as in Example 5. 
Yield: 120 g 55% oil solution of the dispersant comb polymer KP-6. 
Example 7 
Production of a dispersant comb polymer V.I.-improver KP-7 
The following were charged to the apparatus of Example 4: 
36.3 g AMA-1 
3.3 g MEMA 
52.8 g PIB-MM-I 
27.6 g 100N 
After heating to 75.degree. C. under nitrogen, a mixture of 0.2 g IN-1 and 
0.2 g IN-3 was added and the temperature of the oil bath was adjusted to 
105.degree. C. An additional dose of 0.13 g IN-3 was added 4 hours 
following the first initiator addition. The temperature was maintained at 
105.degree. C. for 6 hr thereafter. 
Yield: 120 g 55% oil solution of the dispersant comb polymer KP-7. 
Example 8 
Production of a dispersant comb polymer V.I.-improver KP-8 
The following were charged to the apparatus of Example 4: 
9.9g AMA-1 
3.3 g MEMA 
105.6 g PIB-MM-I 
1.2 g 100N 
After heating to 75.degree. C. under nitrogen, a mixture of 0.10 g IN-1 and 
0.10 g IN-3 was added and the temperature of the oil bath was adjusted to 
105.degree. C. An additional dose of 0.13 g IN-3 was added 4 hours 
following the first initiator addition, and again after another 2 hours. 
The temperature was maintained at 95.degree. C. for 6 hours after the last 
initiator dosing. 
Yield: 120 g 55% oil solution of the dispersant comb polymer KP-8. 
Example 9 
Production of a dispersant comb polymer V.I.-improver KP-9 
The following were charged to the apparatus of Example 4: 
6.6g AMA-1 
3.3 g VP 
3.3 g S 
105.6 g PIB-MM-I 
1.2 g 100N 
After heating to 75.degree. C. under nitrogen, a mixture of 0.2 g IN-1 and 
0.2 g IN-3 was added and the temperature of the oil bath was adjusted to 
105.degree. C. An additional dose of 0.13 g IN-3 was added 4 hours 
following the first initiator addition, and again after another 2 hours. 
The temperature was maintained at 95.degree. C. for 6 hours after the last 
initiator dosing. 
Yield: 120 g 55% oil solution of the dispersant comb polymer KP-9. 
Example 10 
Production of a dispersant comb polymer V.I.-improver KP-10 
The following were charged to the apparatus of Example 4: 
9.9 g AMA-2 
3.3 g MEMA 
105.6 g PIB-MM-II 
1.2 g 100N 
The procedure was otherwise as in Example 9. 
Yield: 120 g 55% oil solution of the dispersant comb polymer KP-10. 
Example 11 
Production of a dispersant comb polymer V.I.-improver KP-11 
The following were charged to the apparatus of Example 4: 
6.6 g AMA-1 
6.6 g MEMA 
105.6 g PIB-MM-II 
1.2 g 100N 
After heating to 75.degree. C. under nitrogen, a mixture of 0.2 g IN-1 and 
0.2 g IN-2 was added and the temperature of the oil bath was adjusted to 
95.degree. C. An additional dose of 0.13 g IN-2 was added 4 hours 
following the first initiator addition, and again after another 2 hours. 
The temperature was maintained at 95.degree. C. for 6 hours after the last 
initiator dosing. 
Yield: 120 g 55% oil solution of the dispersant comb polymer KP-11. 
Example 12 
Production of a dispersant comb polymer V.I.-improver KP-12 
The following were charged to the apparatus of Example 4: 
9.9 g AMA-1 
1.65 g MEMA 
1.65 g VP 
105.6 g PIB-MM-I 
1.2 g 100N 
The procedure was otherwise as in Example 9. 
Yield: 120 g 55% oil solution of the dispersant comb polymer KP-12. 
Example 13 
Production of a dispersant comb polymer V.I.-improver KP-13 
The following were charged to the apparatus of Example 4: 
9.9 g AMA-2 
3.3 g MEMA 
105.6 g PP-MM 
1.2 g 100N 
The procedure was otherwise as in Example 9. 
Yield: 120 g 55% oil solution of the dispersant comb polymer KP-13. 
Example 14 
Production of a dispersant comb polymer improver KP-14 
The following were charged to the apparatus of Example 4: 
9.9g AMA-1 
3.3 g MEMA 
105.6 g PP-MM 
1.2 g 100N 
The procedure was otherwise as in Example 11. 
Yield: 120 g 55% oil solution of the dispersant comb polymer KP-14. 
Example 15 
Production of a comb polymer V.I.-improver KP-15 
The following were charged to the apparatus of Example 4: 
27.9 g AMA-1 
32.1 g MEMA 
80.0 g PIB-MM-II 
41.8 g 100N 
After heating to 90.degree. C. under nitrogen, 0.5 g IN-1 was added and the 
temperature of the oil bath was adjusted to 90.degree. C. An additional 
dose of 0.2 g IN-1 was added 4.5 hours following the first initiator 
addition, and again after another 5 hours. 
Yield: 181.8 g 55% oil solution of the comb polymer V.I.-improver KP-15. 
Example 16 
Production of a comb polymer V.I.-improver KP-16 
The following were charged to the apparatus of Example 4: 
26.4 g AMA-1 
26.4 g S 
26.4 g PIB-MM-II 
14.8 g 100N 
After heating to 75.degree. C. under nitrogen, a mixture of 0.13 g IN-1 and 
0.13 g IN-2 was added and the temperature of the oil bath was adjusted to 
95.degree. C. An additional dose of 0.13 g IN-2 was added 4 hr following 
the first initiator addition, and again after another 2 hours. The 
temperature was maintained at 95.degree. C. for 6 hours after the last 
initiator dosing. After termination of the polymerization, the mixture was 
diluted with 26 g 100N-oil. 
Yield: 120 g 55% oil solution of the comb polymer V.I.-improver KP-16. 
Example 17 
Production of a comb polymer V.I.-improver KP-17 
The following were charged to the apparatus of Example 4: 
26.4 g AMA-1 
13.2 g S 
52.8 g PIB-MM-II 
1.6 g 100N 
The procedure was otherwise as in Example 16. 
Yield: 120 g 55% oil solution of the comb polymer V.I.-improver KP-17. 
Example 18 
Production of a comb polymer V.I.-improver KP-18: 
The following were charged to the apparatus of Example 4: 
16.5 g S 
99.0 g PIB-MM-II 
4.5 g 100N 
After heating to 75.degree. C. under nitrogen, a mixture of 0.13 g IN-1 and 
0.13 g IN-2 was added and the temperature of the oil bath was adjusted to 
95.degree. C. An additional dose of 0.13 g IN-2 was added 4 hours 
following the first initiator addition, and again after another 2 hours. 
The temperature was maintained at 95.degree. C. for 6 hours after the last 
initiator dosing. 
Yield: 120 g 55% oil solution of the comb polymer V.I.-improver KP-18. 
Example 19 
Production of a comb polymer V.I.-improver KP-19. 
The following were charged to the apparatus of Example 4: 
26.4 g S 
79.2 g PP-MM 
14.4 g 100N 
After heating to 75.degree. C. under nitrogen, a mixture of 0.13 g IN-1 and 
0.13 g IN-2 was added and the temperature of the oil bath was adjusted to 
95.degree. C. An additional dose of 0.13 g IN-2 was added 4 hr following 
the first initiator addition, and again after another 2 hours. The 
temperature was maintained at 95.degree. C. for 6 hours after the last 
initiator dosing. 
Yield: 120 g 55% oil solution of the comb polymer V.I.-improver KP-19. 
Example 20 
Production of a comb polymer V.I.-improver KP-20 
The following were charged to the apparatus of Example 4: 
13.2 g AMA-1 
26.4 g S 
52.8 g PIB-MM-II 
27.6 g 100N 
The procedure was otherwise as in Example 19. 
Yield: 120 g 55% oil solution of the comb polymer V.I.-improver KP-20. 
Example 21 
Production of a comb polymer V.I.-improver KP-21 
The following were charged to the apparatus of Example 4: 
30.0 g AMA-1 
30.0 g S 
80.0 g PIB-MM-II 
41.7 g 100N 
After heating to 90.degree. C. under nitrogen, 0.5 g IN-1 was added and the 
temperature of the oil bath was adjusted to 90.degree. C. An additional 
dose of 0.2 g IN-1 was added 4.5 hours following the first initiator 
addition, and again after another 5 hours. 
Yield: 181.8 g 55% oil solution of the comb polymer V.I.-improver KP-21. 
Example 22 
Production of a comb polymer V.I.-improver KP-22 
The following were charged to the apparatus of Example 4: 
50.0 g BMA 
100.0 g PP-MM 
31.8 g 100N 
After heating to 90.degree. C. under nitrogen, 0.7 g IN-1 was added and the 
temperature of the oil bath was adjusted to 90.degree. C. An additional 
dose of 0.2 g IN-1 was added 4.5 hours following the first initiator 
addition, and again after another 5 hours. 
Yield: 181.8 g 55% oil solution of the comb polymer V.I.-improver KP-22. 
Example 23 
Production of a comb ple 18olymer V.I.-improver KP-23 
The following were charged to the apparatus of Example 4: 
50.0 g BMA 
100.0 g PP-MM 
50.0 g 100N 
After heating to 90.degree. C. under nitrogen, 0.9 g IN-1 was added and the 
temperature of the oil bath was adjusted to 90.degree. C. An additional 
dose of 0.2 g IN-1 was added 4.5 hr following the first initiator 
addition, and again after another 5 hr. 
Yield: 200.0 g 55% oil solution of the comb polymer 
V.I.-improver KP-23. 
Characterization of the Comb Polymer V.I.-Improvers 
The dispersive action of the comb polymer V.I.-improvers was studied with 
laboratory tests. Using a toluene/water emulsifier test (T/W test) the 
interfacial activity of the dispersant V.I.-improvers can be 
characterized, as the ability to stabilize water-in-oil emulsions and/or 
generally the ability to disperse polar substances in a nonpolar organic 
medium. The T/W test serves as a model of the dispersion of polar sludges 
in motor oil. 
Using a carbon black spot test, the ability to disperse finely dispersed 
carbon black in oil was tested. This serves as a model of carbon-particle 
thickening of oils in diesel engines. 
Toluene/Water Emulsification Test 
The additive to be tested for its emulsifying capability was dissolved in 
toluene (to which 20 ppm Oracet Blue B had been added), at a polymer 
concentration of 1 wt. %. 7 mL distilled water and 13 mL of the 1% toluene 
solution were charged successively to a 20 mL graduated Schiff test tube, 
and the mixture was held 15 min in a water bath at 30.degree. C. A uniform 
emulsion was produced by vigorous shaking of the test tube, and the sample 
was re-immersed in the water bath. The separation of the emulsion into 
toluene-, emulsion-, and water layers was observed over the ensuing 24-hr 
period, wherewith, using the graduations, the interfaces (toluene/emulsion 
and emulsion/water) were read at times 5 min, 10 min, 100 min, and 24 hr 
(see FIG. 1a). 
Evaluation 
The emulsifying capability was quantified in units of percent according to 
the scheme presented in FIG. 1b, wherein a characterizing percentage of 
the emulsion present over the observation times from 5 min to 24 hr was 
obtained by determining the ratio of the area A to the total area A+B, 
expressed as a percentage. Polymers with good dispersant capability give 
values greater than 20%. 
Carbon Black Spot Test 
Two stock solutions comprised of the additive to be tested mixed into 
150N-oil (Enerpar (R) 11) were prepared: 
Stock Solution I, with 0.375% content of the polymer, and 
Stock Solution II with 0.75%. 
Two dispersion solutions were prepared from each Stock Solution (testing in 
duplicate). 1.5 g carbon black ("Degussa Spezialschwarz 4", a 
flame-produced carbon black) and 50 g Stock Solution were charged to a 150 
mL glass beaker in each case, and were stirred with an "Ultra-Turrax 
Intensiv" stirrer 30 min at 9000 rpm. Then 20 uL of each dispersion 
solution was delivered as a spot onto "Durieux 122" filter paper. After 48 
hr of uniform storage at 30.degree. C., the spots were evaluated. The 
evaluation was expressed as a percentage, as follows: 
carbon black spot diameter/oil spot diameter--100, for each spot, where the 
oil spot diameter is the diameter of the oil spot surrounding the carbon 
black spot. The overall evaluation of the spot test was expressed as the 
sum of the four percentage values. Products having poor carbon black 
dispersivity give overall values of about 70% or lower, whereas products 
having good carbon black dispersivity give .gtoreq.130%. 
Effectiveness of the Dispersive Comb Polymer V.I.-Improvers 
Table 1 presents the chemical compositions and viscosity data for 
dispersing comb polymer V.I.-improving agents KP-4 through KP-14, and 
their evaluations in the laboratory dispersion tests. All products showed 
good dispersivity in the carbon black spot test, thus capability to 
disperse finely divided carbon. Accordingly, these dispersive comb 
polymers are expected to provide good management of carbon particle 
thickening in diesel engine oils. 
The dispersing comb polymers KP-4, KP-8, KP-10, and KP-11 also showed good 
interfacial activity in the T/W test, and accordingly are expected to be 
well suited for dispersing polar motor oil sludges. 
Effectiveness of the Non-Dispersive Comb Polymer V.I.-Improvers 
Table 2 gives the chemical composition, viscosity data, and shear 
stabilities of comb polymer V.I.-improvers KP-15 through KP-23, as well as 
comparison data for currently used conventional V.I.-improvers based on 
linear PMMA. At equal thickening action KV100, the comb polymer 
V.I.-improvers showed superior shear stability, i.e. a lower permanent 
shear stability index, PSSI [(DIN 51382)), than for the linear PAMA. In 
comparisons of products having similar PSSIS, the comb polymer 
V.I.-improvers show higher thickening action, which leads to savings in 
the amount of polymer used, compared to linear PAMA V.I.-improvers. 
Moreover, in some cases the comb polymer V.I.-improvers show substantially 
higher viscosity indices (compare KP-22 to PAMA V.I.-improvers I, II, and 
III). 
TABLE 1 
__________________________________________________________________________ 
Dispersive Comb Polymer Viscosity Index Improvers 
Viscosity data for 5 wt % 
polymer solution in 150 
Evaluation in 
Dispersion 
measuring oil Test 
Polymer Composition 
Polymer content of 
KV40*) 
KV100*) Toluene/ 
Carbon Black 
Example 
wt % of Monomers Additives (wt %) 
(mm.sup.2 /s 
(mm.sup.2 /s 
VI B#) 
Water-Test 
Spot-Test 
__________________________________________________________________________ 
KP-4 (PIBMM-II)--MEMA 55 62,8 9,88 
142 56% 142% 
80--20 
KP-5 (PIBMM-I)--DNA--MEMA 
55 71,9 11,17 
147 1% 140% 
80--15--4 
KP-6 (PIBMM-I)--BMA--MEMA 
55 61,4 10,10 
151 11% 135% 
80--15--5 
KP-7 (PIBMM-I)--(AMA-1)--MEMA 
55 108,8 
11,97 
99 0% 138% 
40--55--5 
KP-8 (PIBMM-I)--(AMA-1)--MEMA 
55 104,5 
16,12 
166 19% 148% 
80--15--5 
KP-9 (PIBMM-I)--(AMA-1)--S--VP 
55 92,5 13,70 
150 3% 157% 
80--10--5--5 
KP-10 (PIBMM-II)--(AMA-2)--MEMA 
55 98,4 14,98 
160 31% 152% 
80--15--5 
KP-11 (PIBMM-II)--(AMA-1)--MEMA 
55 97,5 15,69 
172 24% 156% 
80--10--10 
KP-12 (PIBMM-I)--(AMA-1)--VP--MEMA 
55 70,0 10,32 
133 8% 164% 
80--15--2,5--2,5 
KP-13 (PPMM)--(AMA-2)--MEMA 
55 120,0 
18,04 
168 1% 148% 
80--15--5 
KP-14 (PPMM)--(AMA-1)--MEMA 
55 116,2 
17,36 
164 6% 161% 
80--15--5 
__________________________________________________________________________ 
*)Dynamic viscosity (KV) 
#)Viscosity index VI B: DIN ISO 2909 
TABLE 2 
__________________________________________________________________________ 
Non-dispersive comp polymer V.I.-improver 
Viscosity data for 5 wt % 
polymer solution in 150 N 
measuring oil (PSSI).noteq.) 
Polymer Composition 
Polymer content of 
KV40*) 
KV100*) DIN 51382 
ASTM-D93 
Example 
wt % of Monomers Additives (wt %) 
(mm.sup.2 /s 
(mm.sup.2 /s 
VI B#) 
(30 Cycles) 
Ref. 
__________________________________________________________________________ 
B 
KP-15 (PIBMM-II)--(AMA-1)--MEMA 
55 66,2 12,56 192 12,4 
40--27,9--32,1 
KP-16 (PIBMM-II)--(AMA-1)--S 
55 70,9 11,90 164 11,3 
20--40--40 
KP-17 (PIBMM-II)--(AMA-1)--S 
55 86,4 13,79 163 18,2 
40--40--20 
KP-18 (PIBMM-II)--S 55 68,7 10,43 139 3,5 15,8 
75--25 
KP-19 (PPMM)--S 55 73,6 12,57 171 13,4 29,2 
60--40 
KP-20 (PIBMM-II)--(AMA-1)--S 
55 62,7 10,51 157 15,5 
40--20--40 
KP-21 (PIBMM-II)--(AMA-1)--S 
55 78,4 12,54 159 10,2 29,2 
40--30--30 
KP-22 (PPMM)--BNA 55 75,9 15,83 223 24,9 
50--50 
KP-23 (PPMM)--BMA 50 66,6 12,87 197 16,6 
50--50 
Comparative Examples: Conventional Linear PAMA-VI-Improvers 
I 70,0 12,87 187 24 45 
II 64,0 11,55 177 14 37 
III 6 28 
__________________________________________________________________________ 
.noteq.PSSI = permanent shear stability index, DIN 51382; with Bosch 30 
pump cycles, ASTMD93 Ref. B; ultrasound method 
*)Dynamic Viscosity: ASTM D 445 
#)Viscosity Index VI B: DIN ISO 2909