DE1165858B - Process for the preparation of copolymers from monomeric esters of polymerizable ethylene carboxylic acids - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Boarding school Class: C08f

Number:
File number:
Registration date:
Display day:

German class: 39 c -25/01

M 40531 IVd / 39 c

February 18, 1959

March 19, 1964

The invention relates to a process for the production of new and valuable copolymers which are suitable for producing excellently adhering surface protection coatings or films and which have unexpectedly valuable properties as lubricating oil additives ¹ .

Lubricating oils, especially those used in internal combustion engines; ³ tend däzu to become thinner and lose their Schmierwirkimg when the engine reaches its operating temperature. When choosing the oil to be used in each case, a compromise must be made in that the oil must not be so thick at normal or low temperatures that the engine can be started only with difficulty, and on the other hand not so thin that it does its lubricating effect loses at operating temperature. The viscosity index of the oil (determined according to ASTM method D 567-53) is generally regarded as a measure of its performance at high temperature: the higher the viscosity index, the better the performance.

Ideally, an additive to improve the viscosity index would be such that it would be a most favorable low temperature (e.g. room temperature or below) is oleophobic and dispersed in the oil remains without precipitating or thickening the oil at these temperatures. When the temperature of the oil increases in the direction of the operating temperature of the engine, the addition should progressively become more soluble and become more homogeneous (using the molecule method for the production of copolymers from monomeric esters of polymerizable ethylene carboxylic acids

Applicant:

Minnesota Mining and Manufacturing Company, St. Paul, Minn. (V. St. A.)

Representative:

Dr.-Ing. H. Ruschke, patent attorney, Berlin 33, Auguste-Viktoria-Str. 65

Named as inventor:

Carl L. Sandberg,

Paul I. Roth, Saint Paul, Minn. (V. St. A.)

Claimed priority:

V. St. v. America of February 19, 1958 (No. 716 013) · · ·· - ·>

Increase in temperature decreases. Usually, a greater stabilizing effect at a given concentration of additive at the expense of lauryl, stearyl, cetylacrylates and - «- methyl acrylates (methacrylates), and short chain acrylates such as ethyl, propyl, butyl; Amyl (fusel oil) acrylates and oi * methyl acrylates ^: (methacrylatesDj

state) in the oil so that it is exactly in 30 have already been used as lubricating oil additives, and is thickened to the extent to which its viscosity is actually included; many multigrade lubricating oils

smaller amounts of these copolymers as a means of improving the viscosity index. They have however, the disadvantages described above.

Thickening of the oil at 37.8 ⁰ C with high molecular weight 35 It is also-known that homopolymers of the additives or with lack of a portion of the Alkylphenoxyalkylacrylatmonomeren that achieves a group of possible improvement of the viscosity index of the inventively prepared Mischmonomeren a low molecular weight additive, which form, also an improvement in the viscosity initial thickening effect is decreased. Show index which is generally comparable to that of the commercial, although attempts have occasionally been made, to the thickening effect of the additive in the interests of the type indicated, which was initially customary open-chain acrylate copolymers. This homo of a good viscosity index improvement to polymers of aromatic substituted acrylate encountered by using a lighter oil, ζ. B. an SAE monomer show a significant improvement in the 10-oil, instead of a SAE 20 oil as a basis viscosity index at the expense of the shear strength and chose, so this process is often unsatisfactory, 45 do not act as a pour point depressant for the oil because the lighter lower boiling fractions of lubricating oils to which they have been incorporated; in

than the heavier oil contains.

The copolymers produced by the process of the invention are characterized by their ability to Narrowing this compromise range especially 5 & valuable as lubricating oil additives.

Copolymers of long-chain acrylates, as in some cases they even increase the pour point of the Lubricating oil blend significantly above that of the underlying lubricating oil.

It has been found, however, that the copolymers prepared according to the invention in certain fundamentally as both lubricating oil additives

409 539/587

The preferred mixed monomers have the following structural formulas:

A-OOC -C = CH ₂

where A is the remainder of the saturated aliphatic monohydric primary alcohol and Z = H or a lower alkyl, preferably a methyl group ,, is; · and

O Z

the copolymers of long and short-chain acrylates that do not contain any aromatic substituents, as well as the homopolymers with aromatic substituents and the homopolymers aromatically substituted acrylates are unexpectedly superior.

There has now been a process for the preparation of copolymers from monomeric esters of polymerizable Ethylenecarboxylic acids with 3 to 5 carbon atoms and molecular weights of not more than about 130, with the ethylene double bond in conjugation with a carboxyl group, found by polymerizing the monomers in the presence of catalysts, which is characterized is that one has two acids, one of which is saturated with a primary monohydric alcohol with 1 to 12 carbon atoms and no more than one heteroatom in the chain, which is oxygen,

and the other with a monoalkylphenyl ether in which R is an alkyl radical with 9 to 18 KonlenstofErtomen lower 1,2-alkylene glycol with less than 4 alkylene 20 j _st , ζ has the meaning given above and. η I, 2 oxy units in the glycol chain is esterified, poly or 3. merized.

The den

O - (CH ₂ - CH ₂ - O) _n C ₂ -C = CH

have the acids on which they are based, copolymers prepared according to the invention following general structural formula:

X-CH = C-COOH

A process for the preparation of the monoalkylphenyl ethers of lower 1 ^ -alkylene glycols and the subsequent esterification of the resulting phenyl-substituted Alcohol with a polymerizable ethylene carboxylic acid is used in the following for the preparation of 3-Pentadecylphenoxyäthyl'aeryrat be ^ wrote.

No protection is sought for the production of this compound and its homologues.

wherein X = H, CH ₃ or COOH, Y = H, CH ₃ , "". , _u -,. ,

C ₂ H ₅ or CH ₂ - COOH, X and Y are not the same - Preparation of 3-Pentadecylphenoxyathyterylat

early COOH groups can be, the number of a tared, 2 1 three-necked flask with

Carbon atoms, however, only 3 to 5 and the molecular stirrer, dropping funnel and distillation unit should not be more than about 130. To 35 was seen, was charged with 1,200 g (approximately 4 mol) of this group of acids including acrylic, methacrylic, 3-pentadecylphenol and to approximately 6O ⁰ C ethacrylic, itaconic, maleic and fumaric acids. heated, the 3-pentadecylphenol became liquid.

The preferred acids of this group are those which have been maintained at this temperature Acrylic acid series, namely acrylic, methacrylic and the dropping funnel 40 g (0.22 mol) potassium hydroxide Ethacrylic acid. These acids and their esters are added in methanol (30% solution). The mixture

^{was then heated to 90 °} C. under 1 mm Hg and the volatile constituents were distilled off. The resulting alkaline mixture was then ^{heated to 163 °} C. at atmospheric pressure and relieved at this temperature. The from esters of methacrylic acid 45, while through a large capillary tube a prepared copolymers have as a lubricating stream of ethylene oxide for about 2V ₄ hours oil additives better pour point depression properties were passed, whereupon 194 g (4.4 mol) absorbed than those from acrylic acid esters. were or reacted with the alkaline mixture

The first used in the method of the invention. Then the mass was reduced to about 100 ° C. mixed monomers is cooled in a known manner by 50 and with 15 g of concentrated hydrochloric acid in Esterification of one of the acids given above was neutralized with 15 g of water. This neutral mass

special acrylic and methacrylic acids and their esters, easily copolymerize in very different Proportions. Furthermore, they are available in large quantities, so that their application is extraordinary

the saturated aliphatic (or alicyclic) primary monohydric alcohol with 1 to 12 carbon atoms manufactured. Preferred are esters of

was freed from water at 100 ^° C. and 25 mm Hg. The dehydrated mass was then filtered through a Buchner funnel ^{at 100 to HO 0 C, and the filtrate}

short chain aliphatic alcohols from 1 to 55 were caught. It was then at 1.5 mm Hg

6 carbon atoms, such as methyl, ethyl, propyl, butyl, 2-ethylbutyl, amyl (amyl alcohol mixtures are available as fusel oil) or hexyl alcohol.

The second mixed monomer is also an ester of one of the acids listed above (which are the same Acid as in the first mixed monomer or a different one), the acid with a monoalkylphenyl ether a lower 1,2-alkylene glycol, d. H. Ethylene or propylene glycol, with less than

distilled in a 2 l flask on which a column of 2.2 x 30 cm filled with metal spirals was attached. 1209 g of practically pure / 3- (m-pentadecyl-phenoxy) -ethanol were collected between 222 and 224 ° C in four fractions which had the same melting point of 48.5 to 49.5 ° C. The percentage of free 3-pentadecylphenol was found to be less than 0.1%.
The compound obtained can easily be with

4 alkyleneoxy units are esterified in the glycol chain, 65 is esterifying acrylic or methacrylic acid. By and the alkyl substituent of the alkylphenyl ether group esterification are alkylphenoxyalkylacrylic acid esters

Contains 9 to 18 carbon atoms. The preferred monomer is 3-pentadecylphenoxyethyl methacrylate.

forms, such as B. 3-pentadecylphenoxyethyl acrylate. Generally these compounds can be used as alkylphenoxy

alkyl and alkylphenoxyalkoxyalkyl acrylates.

The methacrylate as well as other similar acrylates and methacrylates were used in a corresponding manner Terminal alkylphenoxy groups produced, including nonylphenoxyethyl acrylate, dodecylphenoxyethyl acrylate and 3-pentadecylphenoxypropyl acrylate.

The copolymers produced therefrom are in

generally translucent to transparent wax copolymers in amounts of about 20 to 95 molar substances to light, rubbery solids. percent of the polymer is included. Further should They are soluble in common organic solvents and stick well to common building materials such as Wood or metal. They can therefore be used as firmly adhering protective coatings for a large number of upper 15 surfaces serve and are characterized by increased light resistance. They also deliver when they are polymerized in emulsion, dispersions from which water-insensitive films are cast can. 20 meant the preferred monomer mixture.

The general method of the invention, according to which if the average chain length of the end

bound M _{1 can be found} in the finished copolymer.

The unexpected advanced properties of those made by the process of the invention Copolymers result from the following versions:

Copolymers in which the monomers are particularly effective as lubricating oil additives terminated with an alkylphenyl group in the finished

the polymer, in particular as an additive to oils based on paraffin or wax, is terminal in the side chain Alkyl groups with an average chain length of about 6.5 to 10 carbon atoms to have. By "terminal alkyl group" is either R, the alkyl group on the phenyl ring, or A, the alkyl (or Alkoxyalkyl) group which represents the remainder of the saturated monohydric primary alcohol in

the copolymers are produced is set out in the following example.

example

To a mixture of 80 parts by weight of the acrylate of 3-Pentadecylphenoxyäthylalkohol and 20 parts by weight of ethyl acrylate in 100 parts by weight heptane 2 parts by weight of benzoyl peroxide were added, followed by heated under gentle agitation to 6O ⁰ C. After 90 hours, the solution of the copolymer was diluted with 10 parts by weight of methanol, and the copolymer was separated off, washed and dried. The copolymer obtained was a pale colored rubber-like substance; Yield about 69%. The copolymer was more than about 2 percent by weight soluble in a light mineral oil and had an intrinsic viscosity in benzene at a concentration of 0.2 g per 100 ecm of solvent of 0.71. The intrinsic viscosity

(τ / ^ solution)

111 ~ ~ ~

(η solvent) C

was based on the method described by P. J. F1 ο r y in “Principles of Polymer Chemistry ", pp. 308-310, Cornell University Press, Ithaca, New York, 1953 certainly.

A number of copolymers were prepared by the above process with different proportions of mixed monomers. In certain cases, a 25- or 33 ° / _o solution constant alkyl groups in the polymer was less than about 6.5, the monomer precipitates from the base oil. If the chain length is greater than about 10, the polymer loses its thickening effect at high temperature. In naphthenic or aromatic base oils, however, the average chain length of the terminal alkyl group of the polymer can be shortened to 5.5 without the polymer precipitating from the oil.

The most valuable alkyl and alkoxyalkyl acrylates and methacrylates are those that have about 6 carbon atoms and less in the alkyl or alkoxyalkyl group, d. i.e., hexyl acrylates and methacrylates and under. When the number of carbon atoms in the alkyl chain of the alkyl acrylate mixed monomer is increased above about 6 carbon atoms, the resulting polymers tend to be in to become more soluble in the base oil and thus show a corresponding decrease in the improvement of the Viscosity index compared to polymers containing alkyl acrylates with shorter chains. To the effectiveness of these new copolymers as a means of improving the viscosity index To determine, they were various base oils in amounts of about 2 percent by weight of the resulting Solution incorporated. In addition, commercial additives were incorporated into the same base oils in the same amount and compared the resulting lubricating oil masses with one another and with the oils without any additives. The results with two base oils are shown in Tables III and IV, respectively. Base oil 5 of Table III is a light, highly purified Pennsylvanian mineral oil consisting essentially of a mixture of

40

in heptane instead of the above-mentioned 50% strength 55 paraffins. Base Oil 9 of Table IV is

Solution used. Further, the temperature of the copolymerization was in some cases about 55 and not 6O ⁰ C.

A list of the monomers used and the abbreviations of their names is given in Table I. A list of the copolymers is given in Table II. The symbol M ₁ denotes the monomer with a terminal alkylphenoxy group and M ₂ the monomer with a terminal alkyl group.

The polymerization rates of the monomers are quite close to one another; they are from Table II by comparing the mole percent of M ₁ in the monomer mixture with the mole percent of a highly purified central continental oil useful as a light lubricating oil for automotive engines. The commercially available additives A, B, C and D consist of copolymers of long and short-chain methacrylates, generally of lauryl and n-butyl methacrylates.

The copolymers 1 to 10 typically show the same or greater improvement in the viscosity index than the usual additives, while without exception they have a smaller thickening effect on the base oil at 37.8 ° C. compared to additives in the same range of intrinsic viscosity [η] . Perhaps even more instructive is a comparison

of substances with a comparable molecular weight, e.g. B. the commercial addition C, the inner Has a viscosity of 1.40 in benzene, compared to the copolymers 7 and 11, which have the internal viscosities 1.32 and 1.42 respectively. The commercial additive increased the kinematic viscosity of the base oil by about 29 cSt at 37.8 ° C, whereas the mixed polymer 7 them only by 12 cSt and the mixed polymer 11 they only increased by 10cSt, while improving the viscosity index over the commercial additive was increased by 12 or 19 viscosity units.

The unexpected superiority of these new copolymers is also due to the viscosity ratio

polymers 6 and 8 also shows the ratio of low temperature thickening to stiffening at high temperature. Copolymer 8 does have a higher viscosity index, but it does a lower viscosity ratio, thus achieving a higher viscosity index at the expense of a strong initial oil thickening at the lower reference temperature.

The polymers selected for comparison with additives A, B and C in Table IV were selected from the point of view that their molecular weights should be around those of the commercially available Additives lying around. The same results were obtained when comparing these polymers with those in Labora

of the three additives with the corresponding internal viscosity produced polymers of lauryl metha-

expressed. The viscosity ratio is defacrylate-ethyl methacrylate (57:43); lauryl methacrylate is the ratio of the internal viscosities
98.9 ^C C and at 37.8 ° C:

[η] 98.9 ° C
b?] 37.8 ° C

n-butyl methacrylate (51:49) and lauryl methacrylate— Ethoxyethyl acrylate (58:42) achieved, the proportions in brackets being the molar ratios indicate the monomers combined in the polymer.

Since the effect of an additive as a means of improving the viscosity index is unrelated with its effect as a pour point depression

medium stands for the added oil, comparative tests were made with a dewaxed light mineral oil with a kinematic viscosity of 9.56 cSt at 37.8 ° C, a viscosity index of 87 and a normal pour point of -62.2 ° C.

A sample of this oil was given 2 percent by weight of 3-pentadecylphenoxyethyl acrylate homopolymer; a second sample 2 percent by weight of a copolymer of 3-pentadecylphenoxyethyl acrylate and Amyl (fusel oil) acrylate (42:58); and a third

If the commercial additive C has a viscosity ratio of 1.18, do the copolymers have? and 11 viscosity ratios of 1.56 and 1.98, respectively, from which it can be seen that the present invention Copolymers have increased in size by 1.5 to 2 times at the increased temperatures, whereas the size of the customary addition remains relatively unchanged. It looks like, that with the commercial additives the improvement in the viscosity index is more of the initial thickening effect depends on the base oil than in the case of the polymers according to the invention.

As can be seen, the copolymers improve 12 35 sample, 2 percent by weight of a commercially available sample

and 13 incorporates the viscosity index significantly less than the A additive. The sample that the homopoly-

other copolymers of the series. That was incorporated as a smear merisate now showed a pour point

oil additives preferred copolymers are those of ^ -15 ° C, whereas the samples, which the mixed

those who incorporate side chains with terminal alkyl polymer and the commercially available additive

groups whose chain length had become about 6.5 to 40 have pour points -59.4 and -60 ° C, respectively

Is 10 carbon atoms. In the mixed polymer had.

seeds 12 and 13 is the average chain oil with a common automotive lubricating oil length more than 12, and therefore its effectiveness is marking SAE 10, a kinematic visgering, The lubricating oil blends of Table IV from the pour point of + 9.4 ° C became the 3-pentadecylphene speak Multigrade motor vehicle engine lubricant - oxyethyl acrylate - amyl acrylate - copolymer in oil from SAE LOW-20. incorporated in an amount of 2 percent by weight, wherein In Table IV, the copolymers 6, 8 show the pour point was lowered to -28.9 ° C, a and 11, a larger increase in size than the effect that that of the commercial additive A commercial additives, which corresponded to the higher viscose 50.

operational relationships can be recognized. The practical training also shows the advantages of this new mixing effect this increase comes from the comparison of polymers with regard to their thickening effect the viscosity at 37.8 ° C with the viscosity improvement at high temperature on the base oil to which it concretes emerged. The copolymer 6 increased the ingestion, not at the expense of the shear strength Viscosity of the oil at 37.8 ° C only reached by about 9 cSt at 55. Rather, it can be used to achieve the same an increase in viscosity index by 47 units, improvement in viscosity index as with a whereas the commercial addition B, which is also the commercial addition of the type used here Viscosity index increased by 47, the viscosity of more shear-resistant polymer according to the invention, 37.8 ° C increased by about 27 cSt. This difference d. H. one of lower molecular weight, verist by the viscosity ratios of the respective 60 are applied. It follows from this that with the same seer additions predictably, the additive B had the strength of the polymer produced according to the invention a relatively good viscosity index improvement causes a higher improvement in the viscosity index tion, but a lower viscosity ratio (1.20) than the comparable commercial additive, This is an indication of the undesirable initial The polymers prepared according to the invention Thickening effect of the additive in the oil at 65 can be beneficial lubricating oils in amounts of about lower reference temperature of 37.8 ° C, which is from 0.1 to about 10 percent by weight, preferably no more is not apparent from the viscosity index values. One as 5 weight percent, can be incorporated. To the Comparison of the viscosity ratios of the mixing easier mixing with the lubricating oils can the

ίο

Polymers in concentrations up to about 30 or The acrylate and methacrylate copolymers,

40 percent by weight in the base oil in the trade, which represent a preferred group, can also

be brought. The base oil can also be emulsified in whole or in part by esters of others above

Inhibitors, stabilizers, cleaning agents and / or specified acids are replaced by valuable

contain other additives in any way. 5 copolymers to be obtained.

Table I.

M ₁

abbreviation

M ₂

abbreviation

3-pentadecylphenoxyethyl acrylate

Il

O-CH ₂ -CH ₁ -OC-CH = CH ₂

S-pentadecylphenoxyethyl methacrylate

O CH ₃

! I I

0-CH ₂ -CHo-OCC =

JC ₁₅ H ₃

Nonylphenoxyethyl acrylate

O-CH ₂ -CH ₂ -OC-CH = CH ₂

Dodecylphenoxyethyl acrylate

Q-CH ₂ -CH ₂ -OC-CH = CH ₂

S-pentadecylphenoxyethoxyethyl acrylate

O - (CH ₂ - CH ₂ - O) ₂ - C - CH = CH ₂

CEA

CEMA

NPEA

DPEA

CEEA

Ethyl acrylate
Amyl (fusel oil) acrylate
Lauryl methacrylate
Ethoxyethyl acrylate

Ethyl acrylate EA Ethyl methacrylate EMA n-butyl methacrylate nBMA n-amyl methacrylate nAMA Fusel oil acrylate FOA 2-ethylbutyl acrylate ^: 2EBA 2-ethylbutyl methacrylate 2EBMA Ethoxyethyl acrylate EEA Fusel oil acrylate FOA

Fusel oil acrylate

2-ethylbutyl acrylate

EA FOA

LMA EEA

FOA

2EBA

409 539/587

Table 1 (continued)

M ₁ abbreviation M _s Fusel oil acrylate abbreviation 3-pentadecylphenoxypropyl acrylate CPA FOA CH ₃ O O-CH ₂ -CH-O-C-CH = CH ₂

Table II

Γ CEMA Λ / Γ Mole percent Mi in that Mole percent bound Mj M ₁ / "" ¹ T " ¹ AJ JVl ₂ Monomer mixture in the copolymer CEA { : EA 6 to 83 7 to 80 I. : FOA 4 to 59 4 to 65 NPEA : LMA 39 to 66 - DPEA : EEA 26 to 40 28 to 46 CEEA : EA 36 to 49 38 to 58 CPA : EMA 52 - : nBMA 25 to 37 17 to 38 : nAMA 27 35 : F0A 19 to 51 17 to 46 : 2EBA 27 21 : 2EBMA 25 to 33 28 to 38 : EEA 45 to 55 46 to 66 : F0A 40 to 80 : F0A 37 to 78 : 2EBA 90 : F0A 50

Table III

M ₁ M _a 2EBMA Mole percent Γ Ί Kinematic Viscosity Viscosity average Mixed FOA bound
1 \ Λ bß viscosity index relationship liche polymer Base oil 5 FOA IVi ₁ ϊη
Dan 7Y-J at 37.8 ° C terminal EEA _DC1 IZ, (Jl (cSt) 111 Chain length ¹ ) FOA - 17.93 167 1.19 A. nAMA -. 0.61 29.32 166 1.19 - B. FOA - 0.98 34.28 164 - C. CEMA EA - 1.40 47.07 177 - D. NPEA FOA 38 1.15 34.07 168 - 1 CEMA FOA 41 0.42 22.96 168 9.4 2 CEA EEA 55 0.41 23.88 171 6.6 3 CEMA LMA 46 0.70 28.02 174 10.5 4th CEMA LMA 22nd 0.73 21.51 175 9.6 5 CEMA 35 0.83 27.89 176 7.2 6th CEMA 29 0.54 22.91 176 8.5 7th CEA 38 1.32 30.09 178 7.9 8th CEA 27 0.78 23.50 179 6.9 9 CEMA 20th 0.55 26.21 179 7.8 10 CEA 46 0.54 26.21 183 7.0 11 CEA 78 1.42 27.54 149 9.6 12th 49 0.21 21.94 151 14.3 13th 0.27 23.85 1.18 13.5 1.33 1.43 1.63 1.31 1.78 , 43 , 71 , 56 , 72 , 59 , 59 , 98 , 09 , 02

Average chain length of the radicals A [formula (I)] and R [formula (2)].

Table IV

Mixed M ₁ M2 nAMA Mole percent ψ Kinematic
viscosity Viscosity Viscosity average
liche polymer EA bound
Vf. in
Rf ¹ TI 7f \\ at 37.8 ° C index relationship terminal Base oil 9 EEA IVl 1 (cSt) Chain length ¹ ) CEMA 32.60 100 6th CEMA 35 0.54 41.78 147 1.64 8th CEMA 38 0.78 50.78 156 1.59 11 46 1.42 62.40 161 1.78 A. - 0.61 53.49 143 1.17 B. - 0.98 60.26 147 1.20 C. - 1.15 58.29 152 1.34

Average chain length of the radicals A [formula (I)] and R [formula (2)].

Claims (1)

Claim: Process for the preparation of copolymers from monomeric esters of polymerizable Ethylenecarboxylic acids with 3 to 5 carbon atoms and molecular weights of not greater than about 130, with the ethylene double bond in conjugation with a carboxyl group stands, by polymerizing the monomers in the presence of catalysts, characterized in that that one has two acids, one of which is with a saturated primary monohydric alcohol with 1 to 12 carbon atoms and no more than one heteroatom in the chain which is oxygen and the other with a monoalkyl phenyl ether a lower 1,2-alkylene glycol is esterified with less than 4 alkyleneoxy units in the glycol chain, polymerized. 409 539/587 3.64 ® Bundesdruckerei Berlin