CA2034144C

CA2034144C - Engine oil containing phenol alkoxylates

Info

Publication number: CA2034144C
Application number: CA002034144A
Authority: CA
Inventors: Helmut Mach; Helmut Schmidt; Knut Oppenlaender; Roland Schwen; Juergen Mohr
Original assignee: BASF SE
Current assignee: BASF SE
Priority date: 1990-01-16
Filing date: 1991-01-15
Publication date: 1999-06-08
Anticipated expiration: 2011-01-15
Also published as: EP0438709B1; CA2034144A1; DE4001043A1; ES2042180T3; ATE88496T1; DE59001259D1; EP0438709A1

Abstract

Engine oils containing up to 10% w/w of a base oil component comprising a reaction product of an alkylphenol or bisphenol A with butylene oxide or butylene oxide/propylene oxide. These engine oils show improved high-temperature stability and improved piston cleaning properties.

Description

~ 20 34 t44 ~

ENGINE OIL CONTAINING PHENOL ALKOXYLATES

The present invention relates to an engine oil having a content of phenol-started oil-soluble polyethers for improving piston cleanliness in automobile engines.

Modern lubricants (engine oils) must satisfy increasing demands to promote wear reduction, longer running times, 10 reduction of deposits, engine cleanliness and improved low-temperature properties. Since only a limited amount of additives may be used and the amount of detergents used in internal combustion engine oils may not exceed a specific value, and since the use of wear protectants (zinc dithiophosphates) is restricted because of the three-way catalytic converters and the presence of too much dirt dispersant can cause attack on the rubber seals, attempts are being made to improve the performance of engine oils by the use of novel base oils. It is thus an object of the present 20 invention to provide novel engine oil components which improve performance significantly over the prior art.

This object is achieved by an engine oil containing, as base oil component, from 1 to 10% w/w of an alkylphenol alkoxylate of the formula:

R1-[O-(R2-O)nH]m in which 30 R1 is an alkylphenol radical having up to 2 alkyl radicals of from 6 to 24 carbon atoms or is a bisphenol radical, R2 is a radical of butylene oxide or butylene oxide/
propylene oxide, n is an integer from 10 to 100 and m is 1 or 2.

la ~ 1 4 4 ~4 In a preferred embodiment of the invention those compounds of the above formula are used in which R2O is derived from a mixture of butylene oxide and propylene oxide containing not more than 80% of propylene oxide or, preferably, from butylene oxide alone.

The phenol component is alkylated with 1 or 2 alkyl radicals having from 6 to 24, preferably 9 to 12, carbon atoms or comprises a bisphenol.
The reaction of the phenol with butylene oxide or with a mixture of butylene oxide and propylene oxide or with butylene oxide followed by propylene oxide or vice versa is effected .

EIASF Akti~n~ llcchaft 2 O.Z.005~/41346 100, preferably from 10 to 50, moles of alkylene oxide are reacted per OH
group of the phenol.

We particularly prefer to react from 5 to 25 moles of butylene oxide alone 5 per phenol group.

Specific examples of suitable alkylphenols are dodecylphenol, nonylphenol and bisphenol A.

The preparation of the polyethers is described below in detail.

Preparation Example (in general) Reaction of alkylphenol or bisphenol A with alkylene oxide(s) In a stirred autoclave, finely pulverized KOH is stirred into the alkylphe-nol and heated to 130~C under a pressure of 200 mbar, the amount of KOH be-ing 0.lZ w/w of the total mixture. This procedure removes residual traces of water. The autoclave is then sealed, and alkylene oxide is pumped in so 20 as to set up a pressure of not more than 6 bar. Different alkylene oxides may be introduced concurrently or consecutively so as to form random polyethers or blocks having more or less distinct transitions. Following the feeds of alkylene oxides, the pressure drops to 2 to 3 bar over a pe-riod of from 3 to 10 hours. ~hen this pressure has been reached, the tem-2s perature is reduced to 80~C and the autoclave is depressurized via a di-aphragm valve and evacuated to 20 to 30 mbar. After this reduced pressure has been maintained for about 1 hour, equivalent amounts of acid ion ex-changers are added to remove potassium and the mixture is filtered.

30 The following products were prepared using the above method:

A: Isononylphenol is reacted with l-butene oxide in a molar ratio of 1:24. The resulting polyether has a viscosity of 320 mm2/s at 40~C and a calculated molecular weight of 1848.

B: Isononylphenol is reacted with l-butene oxide in a molar ratio of 1:8.
The resulting polyether has a viscosity of 130 mm2/s at 40~C and a calculated molecular weight of 796.

C: Isononylphenol is reacted with l-butene oxide and propene oxide in a molar ratio of 1:12:12. The resulting polyether has a viscosity of 125 mm2/s at 40~C and a calculated molecular weight of 1684.
3 ) BASE Alctia"R~5~ ft 3 O. Z 0050/41346 203414~
D: Nonylphenol is reacted with Propene oxide in a molar ratio of 1:10.
The resulting polyether has a viscosity of 87 mmZ~s at 40~C and a molecular weight of 806.

E: Bisphenol A is reacted with butene oxide in a molar ratio of 1:10. The resulting polyether has a viscosity of 360 mm2/s at 40~C and a molecular weight of 878.

F: Bisphenol A is reacted with butene oxide in a molar ratio of 1:15. The o resulting polyether has a viscosity of 320 mm2/s at 40~C and a molecular weight of 1238.

G: Bisphenol A is reacted with butene oxide in a molar ratio of 1:25. The resulting polyether has a viscosity of 380 mm2/s at 40~C and a molecular weight of 1958.

Engine oils are liquids based on selected base oils to which additives(active substances) are added in order to achieve special effects within the engine, for example to keep the engine clean, to reduce deposits, to 20 improve high-temperature resistance, to reduce wear and to make longer running times possible (cf. dlfibel Aral, 10th Edition 1989.1, pp. 23-30, and 1989.2, pp. 4-9).

The alkylphenoxylates to be used in accordance with the present invention 25 are added to engine oils, particularly those based on hydrocarbons, in amounts of up to 10% and in particular amounts ranging from 1 to 8%, by weight.

A representative engine oil mixture contains, for example, the following 30 essential components:

from 80 to 95~O w/w of base oil components, from 0.5 to 2.5% w/w of viscosity index improvers (1007, strength), from 1.5 to 10% w/w of ashless dispersants, 35 from 1.5 to 8% w/w of detergents, from 20.5 to 6% w/w of wear protectants, from 1 to 8% w/w of phenoxylates added in accordance with the invention.

The alkylphenoxylates to be used according to the invention show distinctly greater stability at high temperatures than conventional alkoxylates (DTG).

BASF Aktien8esellscha~t 4 O. Z. 0050/41346 2~3~1 4~
The good high-temperature stability and very good lubricating characteris-tics of the alkylphenoxylates to be used in the present invention are par-ticularly apparent in tests carried out on the driving mechanism of automobile engines. The tests were based on a high-quality engine oil API
sSF/CD, to which 5% of alkylphenoxylate was added in each test. Engine pre-qualification tests were carried out by the method of testing piston clean-liness laid down in the MWM Diesel Engine Test, Part B, DIN 51,361, CEC-L-12-A-76. It was found, surprisingly, that the engine oils containing 5% of the alkylphenoxylates proposed by the invention with their ratings of up to 1O79 points (i.e. very good ratings) were clearly superior to the control (engine oil API SF/CD) with its ratings of 67 and 69, as shown in the Table below.

Alkoxylates started, for example, with tridecanol and containing 1-butene 15 oxide as alkylene oxide produced no improvement on the engine test results.

Table MW~-B diesel engine tests on the piston cleaning properties of engine oil 20 blends containing 5% w/w of an alkylphenoxylate proposed by the present in-vention 25 No. Engine Oil Formulation MWM-B Rating 1 Engine oil A (API SF/CD) 67 and 69 2 Engine oil A + 5% w/w of A 76 and 79 30 3 Engine oil A + 5X w/w of B (Co~p. Example) 66 4 Engine oil A + 5X w/w of C 74 35 5 Engine oil A + 5X w/w of D (Comp. Example) 66 6 Engine oil A + 5% w/w of E 75 7 Engine oil A + 5X w/w of F 72 ~o8 Engine oil A + 5% w/w of G 72 M~M-B ratings:
65 76 excellent, 71-75 very good, 66-70 good, 61-65 satisfactory, 50-60 fair.

Claims

1. An engine oil consisting of base oil components and additives and containing, as base oil component, from 1 to 10%
w/w of an alkylphenol alkoxylate of the formula:

R1-[O-(R2-O)nH]m in which R1 is an alkylphenol radical having up to 2 alkyl radicals of from 6 to 24 carbon atoms or is a bisphenol radical, R2 is a radical of butylene oxide or butylene oxide/
propylene oxide, n is an integer from 10 to 100 and m is 1 or 2.

2. An engine oil as claimed in claim 1, wherein R2 0 is derived from butylene oxide.

3. An engine oil as claimed in claim 1, wherein R2 0 is derived from a mixture of propylene oxide and butylene oxide containing not more than 80% molar of propylene oxide.

4. A motor oil as claimed in any one of claims 1 to 3, and containing, as further base oil components, mineral oil, poly-.alpha.-olefins, poly-internal-olefins, hydrocracked oil, dicarboxylates and neopolyol esters.

5. An engine oil as claimed in any one of claims 1 to 4, wherein R1 is the radical of a mono- or di-alkyiphenol having from 6 to 24 carbon atoms in the alkyl moiety.

6. An engine oil as claimed in any one of claims 1 to 4, wherein R1 is a bisphenol A radical.