JP2001354980A - Pour point depressant and oil composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obvtain a pour point depressant which gives a very low pour point for a fuel oil or lubricating oil having a fixed crystallization temperature. SOLUTION: There is provided a pour point depressant for a fuel oil or lubricating oil whose the crystallization starting temperature (ta) and the crystallization finishing temperature (tb), as measured by a differential scanning calorimeter, satisfy the following formula (1): 20 deg.C>=ta>=-40 deg.C and formula (2): 5 deg.C>=tb>=-70 deg.C, wherein the pour point depressant comprises an alkyl (meth) acrylate polymer (A), and (Ta) and (Tb) of (A) satisfy the following formula (3): ta+20 deg.C>=Ta>=ta-10 deg.C and formula (4): tb+20 deg.C>=Tb>=tb-10 deg.C.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a pour point depressant for improving the flowability of fuel oil or lubricating oil, and an oil composition containing the same.

[0002]

2. Description of the Related Art Oils such as fuel oils and lubricating oils, when exposed to low temperatures in winter or in cold regions, have a crystalline alkyl group-containing substance (for example, wax or improved friction characteristics) contained therein. (Additive added for the purpose of growth) grows into large plate-like crystals, which lowers the fluidity and causes problems such as the inability to start or stop a combustion device or drive system device such as an engine. Several proposals have been made as means for solving these problems. As for the fuel oil, for example, a method of adding a vinyl ester copolymer of ethylene-saturated carboxylic acid to the fuel oil is disclosed in JP-B-39-20069 and JP-B-48-2316.
No. 5, JP-A-59-136391, and the like. As for the lubricating oil, a method of adding polymethacrylate to the lubricating oil (for example, see JP-A-54-70305)
No.) has been proposed.

[0003]

However, recent fuel oils and lubricating oils have an increased wax content in crude oil as a raw material and additives added to improve friction characteristics and the like. Since the use of highly crystalline additives has increased, conventional pour point depressants often fail to provide a sufficient effect, and further improvement is desired.

[0004]

Means for Solving the Problems As a result of intensive studies, the present inventors have found that an alkyl (meth) acrylate polymer having a certain crystallization temperature is used for a fuel oil or a lubricating oil having a certain crystallization temperature. Gives an extremely low pour point and has led to the present invention. That is, the present invention provides a pour point drop for fuel oil or lubricating oil whose crystallization onset temperature (ta) and crystallization end temperature (tb) measured by a differential scanning calorimeter satisfy the following formulas (1) and (2). The pour point depressant comprises an alkyl (meth) acrylate polymer (A), and (Ta) and (Tb) of (A)
Is a pour point depressant characterized by satisfying the following formulas (3) and (4). 20 ° C ≧ ta ≧ −40 ° C (1) 5 ° C ≧ tb ≧ −70 ° C (2) ta + 20 ° C ≧ Ta ≧ ta-10 ° C (3) tb + 20 ° C ≧ Tb ≧ tb−10 ° C (4)

In the present invention, a fuel oil or a lubricating oil in which a pour point depressant is used must satisfy the above formulas (1) and (2). The crystallization start temperature and the crystallization end temperature were measured using a UNIX® manufactured by PERKIN-ELMER.
Using a SC7 differential scanning calorimeter, sample (fuel oil, lubricating oil or alkyl (meth) acrylate polymer) 5 mg
Is a crystallization start temperature and a crystallization end temperature observed when the sample is cooled from 140 ° C. to −80 ° C. at an isothermal rate of 10 ° C./min. As fuel oil, JIS No. 1 light oil, JIS
No. 2 light oil, JIS No. 3 light oil, JIS special No. 3 light oil, JIS
A fuel oil derived from crude oil such as heavy oil A is mentioned as the lubricating oil. As the lubricating oil, lubricating oil derived from crude oil such as isomerized paraffin-containing high viscosity index oil, solvent refined oil, MLDW oil, and those lubricating oils A lubricating oil composed of two or more compounds selected from synthetic lubricating oils is exemplified.

The pour point depressant in the present invention must be composed of an alkyl (meth) acrylate polymer (A) and satisfy the following formulas (3) and (4). ta + 20 ° C. ≧ Ta ≧ ta−10 ° C. (3) tb + 20 ° C. ≧ Tb ≧ tb−10 ° C. (4) If Ta and Tb deviate from the above range, the pour point of the oil deteriorates.

[0007] Ta and Tb are expressed by the following equations (5) and (6).
Is preferably satisfied, and more preferably the following expressions (7) and (8) are satisfied. ta + 18 ° C ≧ Ta ≧ ta-8 ° C (5) tb + 18 ° C ≧ Tb ≧ tb-8 ° C (6) ta + 15 ° C ≧ Ta ≧ ta-5 ° C (7) tb + 15 ° C ≧ Tb ≧ tb-5 ° C (8)

The alkyl (meth) acrylate-based polymer (A) usually contains a (meth) acrylate monomer (a) having a linear or branched alkyl group having 1 to 40 carbon atoms as an essential constituent unit. It is. (A)
For example, methyl methacrylate, decyl methacrylate, isodecyl methacrylate, dodecyl methacrylate, isododecyl methacrylate, tridecyl methacrylate, isotridecyl methacrylate, tetradecyl methacrylate, isotetradecyl methacrylate, pentadecyl petamethacrylate, isopentadecyl petamethacrylate, Hexadecyl methacrylate, octadecyl methacrylate, methyl acrylate, decyl acrylate, isodecyl acrylate, dodecyl acrylate, isododecyl acrylate, tridecyl acrylate, isotridecyl acrylate, tetradecyl acrylate, isotetradecyl acrylate, pentadecyl acrylate, isopentadecyl acrylate , Hexadecyl acrylate Octadecyl acrylate. Among these, a (meth) acrylate monomer having a linear or branched alkyl group having 10 to 40 carbon atoms is preferable, and a (meth) acrylate having a linear or branched alkyl group having 12 to 22 carbon atoms is more preferable. It is a monomer. The content of the monomer (a) in (A) is usually 2
0% to 100% by weight, and preferably 30% to 100% by weight in view of co-crystallization with a crystalline substance in oil.
It is.

(A) may contain another radically polymerizable monomer (b) as a structural unit, if necessary. As (b), (meth) acrylate other than (a) ｛hydroxyalkyl (meth) acrylate having 1 to 30 carbon atoms in the alkyl group, 1 to 30 carbon atoms in the alkoxy group, and 2 carbon atoms in the alkylene group ~ 30 alkoxyalkylene glycol (meth) acrylates and the like｝; other than alkyl (meth) acrylates, unsaturated mono- and / or polycarboxylic esters having 1 to 30 carbon atoms in the alkyl group (butyl crotonate, octyl crotonate, Dodecyl rotonate, dibutyl maleate,
Dioctyl fumarate, dilauryl maleate, distearyl fumarate, dioctyl itaconate, dilauryl itaconate, etc .; vinyl aromatic compounds (styrene, vinyl toluene, etc.); vinyl esters (vinyl acetate, vinyl propionate, etc.); Alpha olefins having 10 to 30 carbon atoms (such as decene and dodecene); carboxylic acid compounds (such as maleic anhydride, methacrylic acid, crotonic acid, and itaconic acid); acrolein; conjugated dienes having 4 to 30 carbon atoms ( Butadiene, isoprene, chloroprene, etc.); (substituted) acetylene [the alkyl group has 1 to 30 carbon atoms.
(Propyne, 1-butyne, 1-pentyne, 1-hexyne, etc.) having 6 carbon atoms in the aryl group
To 30 arylacetylenes (phenylacetylene, p
Alkyl vinyl ether [usually an alkyl vinyl ether having a linear or branched alkyl group having 1 to 18 carbon atoms (methyl vinyl ether, ethyl vinyl ether, propyl vinyl ether, butyl vinyl ether, amyl vinyl ether, hexyl vinyl ether, heptyl vinyl ether) Octyl vinyl ether, nonyl vinyl ether, decyl vinyl ether, dodecyl vinyl ether, tridecyl vinyl ether, tetradecyl vinyl ether, pentadecyl vinyl ether, hexadecyl vinyl ether, octadecyl vinyl ether, etc.]; alkyl allyl ethers [usually, linear or branched having 1 to 18 carbon atoms] Alkyl allyl ether having an alkyl group (methyl allyl ether, ethyl Lyl ether, propyl allyl ether, butyl allyl ether, amyl allyl ether, hexyl allyl ether, heptyl allyl ether, octyl allyl ether, nonyl allyl ether, decyl allyl ether, dodecyl allyl ether, tridecyl allyl ether, tetradecyl allyl ether, pentadecyl Allyl ether, hexadecyl allyl ether, octadecyl allyl ether, etc.], and may contain one or more kinds of monomers.The content of the monomer (b) in (A) is Usually, it is 0 to 20% by weight, preferably 0 to 10% by weight.

The SP value of (A) (solubility parameter)
Is usually 8.8 to 10.5, and preferably 8.9 to 10.0 from the viewpoint of controlling the crystal shape of the crystalline substance. The SP value is determined by the Fedors method [Polym. Eng. S
ci. 14 (2) 152, (1974)].

The HLB value of (A) is usually 0.5 to 9.6.
From the viewpoint of controlling the crystal shape of the crystalline substance, it is preferably 0.8 to 6.5. HLB value is H of Griffin
It is a value calculated by LB ("New surfactant introduction", Sanyo Chemical Industries, Ltd. P128).

The weight average molecular weight of (A) is usually 3,000
0 to 500,000, but preferably 5,000 to 300,000 from the viewpoint of controlling the crystal shape of the crystalline substance.
It is. The molecular weight is a weight average molecular weight converted to polystyrene by gel permeation chromatography.

The pour point depressant of the present invention is used by adding to a fuel oil or a lubricating oil. The amount of the pour point depressant is usually 0.001 to 10% by weight based on the fuel oil or the lubricating oil. Preferably it is 0.005 to 5% by weight.

[0014] The oil composition of the present invention may contain other known additives. These known additives include a corrosion inhibitor [eg, an alkenyl succinic acid-based inhibitor, an ester inhibitor of an alkenyl succinic acid, etc.], a rust inhibitor [eg, an ethylene oxide adduct of dodecylamine, octylamine] Etc.), detergents [eg, ethylene oxide adducts of butylamine, ethylene oxide adducts of butanol, etc.], antiwear agents [eg, higher fatty acid mixtures, sorbitan monooleate, glycerin monooleate, etc.], viscosity index improvers [eg. , An ethylene-propylene copolymer, a hydrogenated ethylene-isoprene copolymer, a poly (meth) acrylate-based viscosity index improver, etc.], an extreme pressure additive, a dispersant, and an antioxidant.

The intended use of the oil composition of the present invention is as a fuel oil such as a diesel engine or a boiler, such as light oil, heavy fuel oil A, gasoline engine oil, diesel engine oil,
Automatic transmission oil, continuous transmission oil, hydraulic oil, tractor oil,
Examples include power steering oil, shock absorber oil, and compressor oil.

[0016]

EXAMPLES The present invention will be described below in detail with reference to examples, but the present invention is not limited to these examples.

(Synthesis Example of Alkyl (meth) acrylate Polymer) Synthesis Example 1 A reactor equipped with a stirrer, a heating device, a thermometer, and a nitrogen blowing tube was charged with 28 g of toluene, and a nitrogen atmosphere was prepared.
° C. The reactor was stirred with 250 g of (meth) acrylate (a mixture of octadecyl methacrylate: dodecyl methacrylate = 30: 70 weight ratio) and 1.5 g of 2,2'-azobis-2,4-dimethylvaleronitrile in 20 g of toluene. The entire amount of the dissolved solution was charged into the reactor at an equal rate over 2 hours.
The polymerization reaction was performed at 85 ° C. for a time. After the reaction, 130
The crystallization start temperature (Ta) by differential scanning calorimetry was -7 ° C, the crystallization end temperature (Tb) was -33 ° C, the SP value was 9.0, and the HLB was 1.
8. Polymer 1 having a weight average molecular weight of 150,000 was obtained.

Synthesis Example 2 Octadecyl methacrylate was used as (meth) acrylate:
Polymerization was carried out in the same manner as in Synthesis Example 1 except that a compound having a dodecyl methacrylate = 30: 70 weight ratio was changed to a compound having an octadecyl methacrylate: dodecyl methacrylate = 40: 60 weight ratio. The crystallization start temperature (Ta) is −5 ° C., and the crystallization end temperature (T
b) was −28 ° C., the SP value was 9.0, the HLB was 1.8, and the polymer 2 having a weight average molecular weight of 130,000 was obtained.

Synthesis Example 3 Octadecyl methacrylate was used as (meth) acrylate.
From a formulation having a dodecyl methacrylate = 30: 70 weight ratio, octadecyl methacrylate: hexadecyl methacrylate: isodecyl methacrylate = 18: 42: 4
Polymerization was carried out in the same manner as in Synthesis Example 1 except that the mixture was 0 weight ratio. The crystallization onset temperature (Ta) was -5 ° C and the crystallization end temperature (Tb) was -30 by a differential scanning calorimeter.
C., a polymer 3 having an SP value of 8.9, an HLB of 1.9 and a weight average molecular weight of 170,000 was obtained.

Synthesis Example 4 (Meth) acrylate is octadecyl methacrylate:
Dodecyl methacrylate = 30: 70 weight ratio formulation to octadecyl methacrylate: hexadecyl methacrylate: isodecyl methacrylate = 24: 56: 2
Polymerization is carried out in the same manner as in Synthesis Example 1 except that the mixture is 0 weight ratio. The crystallization onset temperature (Ta) is 2 ° C. and the crystallization end temperature (Tb) is -14 ° C. by a differential scanning calorimeter. ,
SP value 8.9, HLB 1.7, weight average molecular weight 1
40,000 Polymer 4 was obtained.

Synthesis Example 5 Octadecyl methacrylate (meth) acrylate:
Polymerization was carried out in the same manner as in Synthesis Example 1 except that a compound having a octadecyl methacrylate: dodecyl methacrylate = 20: 80 weight ratio was prepared from a compound having a dodecyl methacrylate = 30: 70 weight ratio, and crystals were obtained by a differential scanning calorimeter. The crystallization start temperature (Ta) is −18 ° C., the crystallization end temperature (Tb) is −43 ° C., the SP value is 9.0, and the HLB is 1.
9. Polymer 5 having a weight average molecular weight of 150,000 was obtained.

Example 1 The crystallization onset temperature (ta) of the differential scanning calorimeter was -4.
Solvent refined lubricating oil 1 having a crystallization end temperature (tb) of -41 ° C (100 ° C kinematic viscosity 6.4 mm2 / s, pour point -7.
5 ° C.), 0.1% by weight of polymer 1 was dissolved in oil composition 1
I got The pour point of the oil composition 1 was measured according to JISK-2269. Table 1 shows the results.

Example 2 The crystallization onset temperature (ta) of the differential scanning calorimeter was -5.
° C, a high viscosity index lubricating oil 1 having a crystallization end temperature (tb) of −35 ° C. (100 ° C. kinematic viscosity 4.2 mm 2 / s, viscosity index 1)
03, pour point-10.0 ° C.), 0.1% by weight of polymer 2 was dissolved to obtain oil composition 2. The pour point of the oil composition 2 was measured according to JISK-2269. Table 1 shows the results.

Example 3 10 parts by weight of the polymer 3 and 10 parts by weight of the polymer 5 were weighed in a beaker, heated and mixed at 100 ° C., and the crystallization starting temperature (Ta) was -5 ° C. by a differential scanning calorimeter. Temperature (T
b) was obtained at -43 ° C. The crystallization onset temperature (ta) of the blend of 0.1% by weight as determined by a differential scanning calorimeter was −
Oil composition dissolved in high viscosity index lubricating oil 2 (100 ° C kinematic viscosity 4.1 mm2 / s, viscosity index 103, pour point -12.5 ° C) with 5 ° C and crystallization end temperature (Tb) of -51 ° C 3 was obtained. The pour point of the oil composition 3 was measured according to JISK-2269. Table 1 shows the results.

Example 4 The crystallization onset temperature (ta) of the differential scanning calorimeter was -6.
° C, light oil 1 having a crystallization end temperature (tb) of -11 ° C (cloud point -4.0 ° C, pour point -10.0 ° C, first distillation point of distillation property 2)
03 ° C., distillation property end point 364 ° C.)
By dissolving 1% by weight, an oil composition 4 was obtained. JISK-2269
The pour point of the oil composition 4 was measured according to. Table 1 shows the results.
Shown in

Comparative Example 1 Solvent-refined lubricating oil 1 was mixed with a conventional pour point depressant include 1
38 obtained by membrane dialysis (crystallization start temperature T
a is −17 ° C. and the crystallization end temperature Tb is −39 ° C.).
1% by weight was dissolved to obtain Comparative Oil Composition 1. JISK-22
The pour point of Comparative Oil Composition 1 was measured according to 69. Table 1 shows the results.

Comparative Example 2 Crystallization onset temperature (ta) measured by a differential scanning calorimeter was -38.
° C and a conventional solvent-refined lubricating oil 2 having a crystallization end temperature (tb) of -51 ° C (100 ° C kinematic viscosity 2.3 mm ² / s, pour point -35.0 ° C), used in Comparative Example 1. A conventional pour point depressant Alube 138 was subjected to membrane dialysis to dissolve 0.1% by weight of the obtained polymer to obtain Comparative Oil Composition 2. JISK
The pour point was measured according to -2269. Table 1 shows the results.

Comparative Example 3 The polymer obtained by subjecting the conventional pour point depressant Acryb 138 used in Comparative Example 1 to light oil 1 by membrane dialysis was 0.01%.
% By weight to obtain Comparative Oil Composition 3. JISK-226
The pour point of the comparative oil composition 3 was measured according to No. 9. Table 1 shows the results.

[0029]

[Table 1]

As can be seen from Table 1, the pour point depressants of the present invention significantly lower the pour point of certain oils.

[0031]

As is apparent from the above examples, the pour point depressant of the present invention can remarkably lower the pour point of oil and has a good low-temperature fluidity as compared with the conventional pour point depressant. An oil composition can be provided.

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Claims (5)

[Claims] 1. A pour point drop for a fuel oil or lubricating oil whose crystallization onset temperature (ta) and crystallization end temperature (tb) measured by a differential scanning calorimeter satisfy the following formulas (1) and (2): The pour point depressant comprises an alkyl (meth) acrylate polymer (A), and (Ta) and (T) of (A)
A pour point depressant, wherein b) satisfies the following formulas (3) and (4). 20 ° C ≧ ta ≧ −40 ° C (1) 5 ° C ≧ tb ≧ −70 ° C (2) ta + 20 ° C ≧ Ta ≧ ta-10 ° C (3) tb + 20 ° C ≧ Tb ≧ tb−10 ° C (4) 2. (A) contains an alkyl (meth) acrylate monomer (a) having an alkyl group having 1 to 40 carbon atoms as an essential constituent unit, and the content of (a) is 20 to 1
The pour point depressant according to claim 1, which is 00% by weight. 3. The solubility parameter (SP value) of (A) is 8.8 to 10.5, the HLB value is 0.5 to 9.6, and the weight average molecular weight is 3,000 to 500,000. 1
Or a pour point depressant according to 2. 4. A fuel oil or lubricating oil whose crystallization start temperature (ta) and crystallization end temperature (tb) measured by a differential scanning calorimeter satisfy the following formulas (1) and (2): ) An acrylate-based polymer (A),
And (Ta) and (Tb) in (A) are represented by the following formula (3)
An oil composition comprising a pour point depressant satisfying (4). 20 ° C ≧ ta ≧ −40 ° C (1) 5 ° C ≧ tb ≧ −70 ° C (2) ta + 20 ° C ≧ Ta ≧ ta-10 ° C (3) tb + 20 ° C ≧ Tb ≧ tb−10 ° C (4) 5. The pour point depressant content of the oil is 0.00
The oil composition according to claim 4, wherein the amount is 1 to 10% by weight.