CN103012650B - A kind of copolymer type pour depressant for lubricating oil - Google Patents

Abstract

A copolymer type lubricating oil pour point depressant further improves the pour point depressant effect of the existing pour point depressant. The copolymer type lubricating oil pour point depressant is a mixture of a triblock copolymer or a plurality of triblock copolymers, and the structural formula of the triblock copolymer is as follows: In the formula, n is an integer of 7-17, a, b, and c are respectively an integer of 1-1000, and the viscosity-average molecular weight of the triblock copolymer is 10,000-500,000. The present invention also provides a preparation method of the above-mentioned tri-block copolymer. The pour point depressant of the invention has an excellent pour point depressant effect, which can reach 32°C.

Description

A copolymer type lubricating oil pour point depressant

technical field

The invention relates to a copolymer type lubricating oil pour point depressant, which belongs to the technical field of lubricating oil additives.

technical background

Most of the crude oil produced in my country is high-wax crude oil, especially with the increasing depletion of oil resources, the wax content of newly produced crude oil is getting higher and higher. This kind of crude oil has a high freezing point and poor low-temperature fluidity. The solutions include dewaxing, hydrogenation, adding point depressants, etc. From the perspective of reducing energy consumption and production costs and increasing the economic benefits of enterprises, it is simple to add polymer point depressants with certain functions to waxy crude oil. effective method.

The pour point depressant technology began in the early 1930s and was mainly used in the field of lubricating oil. In 1929, Davis obtained the earliest pour point depressant, Paraflow, by using chlorinated paraffin and naphthalene through the Fride-Craft condensation reaction. In 1931, the pour point depressant named Camel Pool came out. It is a condensation product of chlorinated paraffin and phenol, and its structure is similar to Paraflow. From 1938 to 1948, a new pour point depressant, polyisobutylene, appeared. Since the 1950s, people have continued to develop new type of pour point depressants on the one hand, and modified existing pour point depressants by means of blending and copolymerization on the other hand. From the 1960s to the 1980s, with the increasing production of high-wax crude oil in the world, in order to solve the problems in production, pour point depressants suitable for the properties of crude oil from different origins were successively developed and used in crude oil pipelines.

Since the 1980s, with the increase of crude oil transportation methods and the gradual increase of people's demand for low-sulfur high-wax crude oil, the requirements for pour point depressants have become higher and higher. Some major companies in the world no longer focus on the synthesis or development of new pour point depressants, but have modified or compounded some original products. Chevron Corporation utilizes composite technology to develop a composite agent composed of alkenyl butyramide acid, polyethylene-vinyl acetate, polyethylene-acrylate, and produce a composite pour point depressant with good performance.

Commercial pour point depressants currently used in China, such as polyvinyl acetate-fumarate (polymeric fumaric ester and vinyl acetate, referred to as PFVA, and the Chinese label is T818), are formed by the copolymerization of fumaric acid ester and vinyl acetate. Although the pour point depressant has a certain pour point depressant effect, as the wax content in crude oil increases, the field of lubricating oil urgently needs a pour point depressant with more excellent pour point depressant effect.

Contents of the invention

In order to further improve the pour point depressant effect of the pour point depressant and broaden its application field, the invention provides a copolymer type lubricating oil pour point depressant.

The present invention provides a copolymer-type lubricating oil pour point depressant, which is a triblock copolymer or a mixture of multiple triblock copolymers. The structural formula of the triblock copolymer is as follows:

In the formula, n is an integer of 7-17, a, b, and c are respectively an integer of 1-1000, and the viscosity-average molecular weight of the triblock copolymer is 10,000-500,000.

Preferably, said n is an integer of 11-15, more preferably n is 11 or 13, most preferably n is 13.

Preferably, the viscosity average molecular weight is 10,000-100,000, more preferably 20,000-40,000.

Preferably, the described pour point depressant is a mixture of various triblock copolymers, more preferably the described pour point depressant is a triblock copolymer with n being 11 and a triblock copolymer with n being 13 The mixture is mixed according to the mass ratio of 1:1-7:3.

The present invention also provides the preparation method of above-mentioned triblock copolymer, and this method comprises the following steps:

(1) add fumaric acid higher ester, vinyl acetate and styrene in the device, wherein, the molar fraction of fumaric acid higher ester, vinyl acetate and styrene is respectively 10-80%;

(2) adding consumption is the free radical polymerization initiator of 0.1-1% of the total mass of fumaric acid higher ester, vinyl acetate and styrene;

(3) be heated up to 70-80 ℃, react for 3-8 hours;

(4) underpressure distillation, remove excessive vinyl acetate, obtain triblock copolymer;

The structural formula of described fumaric acid senior ester is In the formula, n is an integer of 7-17.

Preferably, the mole fractions of the higher fumaric acid ester, vinyl acetate and styrene are respectively 20-60%.

Preferably, the amount of the free radical polymerization initiator is 0.5% of the total mass of fumaric acid higher ester, vinyl acetate and styrene.

Preferably, the free radical polymerization initiator is dibenzoyl peroxide or azobisisobutyronitrile.

Preferably, the reaction time is 4-6 hours.

Beneficial effects of the present invention:

The present invention adds the third monomer styrene on the basis of polyvinyl acetate-fumarate copolymer pour point depressant (T818), and obtains a lubricating oil pour point depressant with excellent pour point depressant effect. The pour point depressant can be a single component or a compound component. For base oil 150N, the maximum pour point depressant can reduce the temperature by 19°C. For base oil 150SN, the maximum pour point depressant can reduce the maximum temperature by 32°C. , the depressing effect is obviously better than T818.

Description of drawings

Fig. 1 is the infrared spectrogram of the polyvinyl acetate-fumarate pour point depressant prepared by comparative example 1 of the present invention;

Fig. 2 is an infrared spectrogram of the copolymer-type lubricating oil pour point depressant prepared in Example 1 of the present invention.

detailed description

A three-block copolymer, the three-block copolymer is a terpolymer of vinyl acetate, fumarate and styrene, and its structural formula is as follows:

In the formula, n is an integer of 7-17, a, b, and c are respectively an integer of 1-1000, and the viscosity-average molecular weight of the triblock copolymer is 10,000-500,000.

Preferably, said n is an integer of 11-15, more preferably n is 11 or 13, most preferably n is 13.

Preferably, the viscosity average molecular weight is 10,000-100,000, more preferably 20,000-40,000.

A copolymer-type lubricating oil pour point depressant, the pour point depressant is a kind of above-mentioned three-block copolymer or a mixture of multiple above-mentioned three-block copolymers.

Preferably, the described pour point depressant is a mixture of various triblock copolymers, more preferably the described pour point depressant is a triblock copolymer with n being 11 and a triblock copolymer with n being 13 mixture of substances.

The present invention also provides the preparation method of above-mentioned triblock copolymer, and this method comprises the following steps:

(1) Add fumaric acid higher ester, vinyl acetate and styrene in the device, wherein, the molar fractions of fumaric acid higher ester, vinyl acetate and styrene are respectively 10-80%, fumaric acid higher ester, The sum of the mole fractions of vinyl acetate and styrene is 100%;

(2) adding consumption is the free radical polymerization initiator of 0.1-1% of the total mass of fumaric acid higher ester, vinyl acetate and styrene;

(3) be heated up to 70-80 ℃, react for 3-8 hours;

(4) underpressure distillation, remove excessive vinyl acetate, obtain light yellow, viscous liquid, i.e. triblock copolymer, that is, the copolymer type lubricating oil pour point depressant of single component;

The structural formula of described fumaric acid senior ester is In the formula, n is an integer of 7-17.

When the copolymer-type lubricating oil pour point depressant is a compound component, that is, when a variety of tri-block copolymers are mixed, the various tri-block copolymers are first prepared according to the above method, and the obtained various tri-block copolymers , after mixing, it is a composite component copolymer-type lubricating oil pour point depressant. There is no restriction on the type and proportion of the mixture, and the technical effect of the present invention can be achieved. The embodiment of the present invention provides two base oils, 150N and 150SN Among them, when the average carbon number of n of the block copolymer after compounding is 13, the pour point depressing effect is better, preferably n is the triblock copolymer of 11 and n is the triblock copolymer of 13 by mass ratio 1: 1-7:3 mixing, but the invention is not limited thereto.

The mole fraction of described fumaric acid higher ester, vinyl acetate and styrene is preferably respectively 20-60%, triblock copolymer of the present invention, the proportioning of fumaric acid higher ester, vinyl acetate and styrene Among them, increasing the addition of styrene can improve the pour point depressant effect.

The radical polymerization initiator described in the present invention has no special requirements, preferably dibenzoyl peroxide and azobisisobutyronitrile, and the consumption is preferably 0.5% of the total mass of fumaric acid higher ester, vinyl acetate and styrene .

The polymerization reaction temperature of the tri-block copolymer of the present invention is 70-80°C, which is the temperature for the decomposition of the initiator. The temperature is lower than 70°C, and the polymerization reaction can only be initiated in a small amount, and it takes a long time. The temperature is higher than 80°C. Although the present invention can also be realized, considering the cost of industrialized production, the temperature is too high to lose practical application value.

Preferably, the reaction time is 4-6 hours.

The present invention prepares the reaction equation of triblock copolymer as follows:

Higher fumaric acid esters of the present invention can be purchased commercially and can also be obtained through laboratory preparation. The preparation method is prior art. The present invention provides a method for preparing higher fumaric acid esters, but the present invention is not limited thereto. The method includes the following steps:

(1) Adding higher carbon alcohols with 8-18 carbon atoms and fumaric acid in a molar ratio of 1:0.1-10 to the reaction device;

(2) Adding a solvent with an amount of 40%-300% of the total mass of higher alcohol and fumaric acid;

(3) Raise the temperature of the reaction system to 110-150°C;

(4) Adding consumption is the 1-2% catalyst of high carbon alcohol and fumaric acid gross mass, stirring carries out esterification reaction 3-10 hour, stirring speed 50-500 rev/min;

(5) Distill under reduced pressure to remove the solvent to obtain higher fumaric acid esters.

Preferably, the temperature is raised to 120-140° C. in step (3).

Preferably, in step (4), the stirring speed is 100-200 rpm, and the reaction is performed for 5-6 hours.

Preferably, the molar ratio of the higher alcohol to fumaric acid is 1:0.5-2.

There is no special requirement for the solvent and water agent, preferably benzene, toluene, xylene, cyclohexane or petroleum ether, and the dosage is preferably 60% of the total mass of higher alcohol and fumaric acid.

The catalyst can be any catalyst commonly used in esterification reaction, preferably p-toluenesulfonic acid, and the dosage is preferably 1.4-1.5% of the total mass of higher alcohol and fumaric acid.

The present invention prepares the reaction equation of fumaric acid higher ester as follows:

The copolymer-type lubricating oil pour point depressant of the present invention is suitable for various types of lubricating oils. The pour point depressant is used as a lubricating oil additive. The amount added to the lubricating oil is the prior art, and the added amount is generally not higher than 2wt%. , the higher the added value, the lower the economic value. The preferred amount of pour point depressant added is 0.5wt%. The embodiment of the present invention provides copolymer lubricating oil pour point depressant in 150N and 150SN lubricating oils. The added amount of pour point depressant The pour point depressing effect is 0.1wt%-0.5wt%, but the present invention is not limited thereto.

The detection of the pour point depressant effect of the copolymer lubricating oil pour point depressant of the present invention is a well-known technology in the art, and the national standard GB/T 3535-2006 is adopted.

In order to enable those skilled in the art to further understand the present invention, the present invention will be further described below in conjunction with the embodiments and accompanying drawings.

Comparative example 1

Illustrate Comparative Example 1 in conjunction with Fig. 1

Preparation of polyvinyl acetate-fumarate (T818):

(1) Add 0.1 mol of myristyl alcohol and 0.1 mol of fumaric acid into a reactor with a stirring device, add 60% of the total mass of myristyl alcohol and fumaric acid toluene, add the total amount of myristyl alcohol and fumaric acid 1.5% p-toluenesulfonic acid by mass was polymerized for 5 hours at a temperature of 130° C. to obtain higher fumaric acid esters;

(2) Add 0.1mol of fumaric acid higher ester, 0.13mol of vinyl acetate in the reactor equipped with stirring device and temperature sensing device, add 0.5% of the total mass of fumaric acid higher ester and vinyl acetate Dibenzoyl peroxide was reacted at 70-80°C for 5 hours, and excess vinyl acetate was removed by vacuum distillation to obtain polyvinyl acetate-fumarate pour point depressant with a viscosity-average molecular weight of 430 million. Marked as PFVS01.

PFVS01 was tested for the pour point depressant effect in two base oils, 150N and 150SN, and the dosage of pour point depressant was 0.5wt% (pour point depressant/base oil). The test results are shown in Table 1.

Fig. 1 is the infrared spectrogram of the polyvinyl acetate-fumarate pour point depressant of Example 1 of the present invention, as can be seen from Fig. 1, 1 is -(CH ₂ ) _n -deformation vibration peak, 2 is -COC Stretching vibration peak, 3 is deformation vibration peak of ester, 4 is ester carbonyl stretching vibration peak, 5 is -C-CH ₂ -C-symmetric stretching vibration peak, 6 is -C-CH ₂ -C-asymmetric stretching vibration peak .

Example 1

Embodiment 1 is illustrated in conjunction with Fig. 2

The preparation method of single-component copolymer type lubricating oil pour point depressant:

(1) Add 0.08mol of myristyl alcohol and 0.08mol of fumaric acid into a reactor with a stirring device, add 60% of the total mass of myristyl alcohol and fumaric acid toluene, add myristyl alcohol and fumaric acid 1.5% of the total mass of p-toluenesulfonic acid was polymerized at a temperature of 130° C. for 6 hours to obtain a higher ester of fumaric acid;

(2) Add 0.08mol fumaric acid higher ester, 0.08mol vinyl acetate, 0.08mol styrene in the reactor equipped with stirring device and temperature sensing device, add fumaric acid higher ester, vinyl acetate and 0.5% dibenzoyl peroxide of the total mass of styrene, react at 70-80°C for 6 hours, and distill under reduced pressure to remove excess vinyl acetate to obtain a copolymer-type lubricating oil pour point depressant, viscosity average molecular weight For 65000, marked as PFVS02.

PFVS02 was tested for single-component pour point depressant effect in two base oils 150N and 150SN, and the dosage of pour point depressant was 0.5wt% (pour point depressant/base oil). The test results are shown in Table 1.

Figure 2 is the infrared spectrogram of the copolymer-type lubricating oil pour point depressant in Example 1 of the present invention, 1 is the deformation vibration peak of -(CH ₂ ) _n -, 2 is the stretching vibration peak of -COC, and 3 is the deformation vibration peak of ester , 4 is the ester carbonyl stretching vibration peak, 5 is the symmetrical stretching vibration peak of -C-CH ₂ -C-, 6 is the asymmetric stretching vibration peak of -C-CH ₂ -C-, 7 is the out-of-plane bending of monosubstituted benzene ring CH The vibration peak, 8 is the stretching vibration peak of the skeleton of the benzene ring.

From the comparison of the infrared spectra of Figure 1 and Figure 2, it can be seen that the infrared spectrum of the copolymer lubricating oil pour point depressant prepared in Example 1 with the addition of the third monomer styrene has two more peaks, which are peaks 7 and 8, respectively. Peak 7 represents the C-H out-of-plane bending vibration peak of the monosubstituted benzene ring, and peak 8 represents the skeleton stretching vibration peak of the benzene ring, which proves that the styrene monomer participates in the copolymerization.

Example 2

The preparation method of single-component copolymer type lubricating oil pour point depressant:

(1) Add 0.08mol of myristyl alcohol and 0.08mol of fumaric acid into a reactor with a stirring device, add toluene with 60% of the total mass of myristyl alcohol and fumaric acid, add myristyl alcohol and fumaric acid The p-toluenesulfonic acid of 1.5% of the total mass of the acid was polymerized for 5.5 hours at a temperature of 120° C. to obtain a higher ester of fumaric acid;

(2) Add 0.08mol of fumaric acid higher ester, 0.08mol of vinyl acetate, 0.04mol of styrene in the reactor equipped with stirring device and temperature sensing device, add fumaric acid higher ester, vinyl acetate React with 0.5% dibenzoyl peroxide of the total mass of styrene at 70-80°C for 4 hours, and distill under reduced pressure to remove excess vinyl acetate to obtain a copolymer-type lubricating oil pour point depressant, viscosity average The molecular weight is 55000, and it is marked as PFVS03.

PFVS03 was tested for single-component pour point depressant effect in two base oils 150N and 150SN, and the dosage of pour point depressant was 0.5wt% (pour point depressant/base oil). The test results are shown in Table 1.

Example 3

The preparation method of single-component copolymer type lubricating oil pour point depressant:

(1) Add 0.08mol of dodecyl alcohol and 0.08mol of fumaric acid into a reactor with a stirring device, add toluene with 60% of the total mass of dodecyl alcohol and fumaric acid, add the total mass of dodecyl alcohol and fumaric acid 1.5% p-toluenesulfonic acid by mass was polymerized at 140°C for 5 hours to obtain higher fumaric acid esters;

(2) Add 0.08mol of fumaric acid higher ester, 0.08mol of vinyl acetate, 0.04mol of styrene in the reactor equipped with stirring device and temperature sensing device, add fumaric acid higher ester, vinyl acetate React with dibenzoyl peroxide, an initiator of 0.5% of the total mass of styrene, at 70-80°C for 5 hours, and distill under reduced pressure to remove excess vinyl acetate to obtain a copolymer-type lubricating oil pour point depressant. The viscosity-average molecular weight is 58000, marked as PFVS04.

PFVS04 was tested for the single-component pour point depressant effect in two base oils 150N and 150SN, and the dosage of pour point depressant was 0.5wt% (pour point depressant/base oil). The test results are shown in Table 1.

Table 1 Test of pour point depressing effect of single component

In Table 1, LZ803B is an industrial polyα-olefin pour point depressant; it can be seen from the above table that the pour point depressant effect of PFVS01 (commodity T818) without styrene is obviously lower than that of the pour point depressant with styrene (PFVS02, PFVS03 and PFVS04); the pour point depressing effect of PFVS02 is higher than that of PFVS03 and PFVS04, indicating that the pour point depressing effect increases with the increase of styrene addition; the pour point depressing effect of the single component copolymer type lubricating oil pour point depressant of the present invention It is not as good as the industrial product LZ803B.

Example 4

The preparation method of compound component copolymer type lubricating oil pour point depressant:

The PFVS02 prepared in Example 1 and the PFVS04 prepared in Example 3 were mixed in a mass ratio of 3:7 to obtain a copolymer-type lubricating oil pour point depressant.

The copolymer-type lubricating oil pour point depressant prepared in Example 4 was tested for the pour point depressing effect of the compound components in two base oils 150N and 150SN respectively, and the dosage of the pour point depressant was 0.5wt%, 0.2wt% and 0.1wt% (pour point depressant/base oil), the test results are shown in Table 2, Table 4 and Table 5.

Table 2 Test of pour point depressing effect of compound components

Example 5

The preparation method of compound component copolymer type lubricating oil pour point depressant:

The PFVS02 prepared in Example 1 and the PFVS04 prepared in Example 3 were mixed at a mass ratio of 1:1 to obtain a copolymer-type lubricating oil pour point depressant.

The copolymer-type lubricating oil pour point depressant prepared in Example 5 was respectively tested for the pour point depressing effect of compound components in two kinds of base oils 150N and 150SN, and the dosage of the pour point depressant was 0.5wt% (pour point depressant/base Oil), the test results are shown in Table 4 and Table 5.

Example 6

The preparation method of compound component copolymer type lubricating oil pour point depressant:

The PFVS03 prepared in Example 2 and the PFVS04 prepared in Example 3 were mixed in a mass ratio of 3:7 to obtain a copolymer-type lubricating oil pour point depressant.

The copolymer-type lubricating oil pour point depressant prepared in Example 6 was tested for the pour point depressing effect of the composite components in two base oils 150N and 150SN respectively, and the dosage of the pour point depressant was 0.5wt% (pour point depressant/base Oil), the test results are shown in Table 4 and Table 5.

Example 7

The preparation method of compound component copolymer type lubricating oil pour point depressant:

The PFVS03 prepared in Example 2 and the PFVS04 prepared in Example 3 were mixed at a mass ratio of 1:1 to obtain a copolymer-type lubricating oil pour point depressant.

The copolymer-type lubricating oil pour point depressant prepared in Example 7 was tested for the pour point depressing effect of the compound components in two base oils 150N and 150SN respectively, and the dosage of the pour point depressant was 0.5wt%, 0.2wt% and 0.1wt% (point depressant/base oil), the test results are shown in Table 3, Table 4 and Table 5.

Table 3 Test of pour point depressing effect of compound components

Table 4 Test of pour point depressing effect of compound components

Table 5 Test of pour point depressing effect of compound components

It can be seen from the above table 2-5 that, for the base oil 150N, the pour point depressant after compounding can reduce the temperature by up to 19°C, reaching the effect of industrial polyα-olefin pour point depressant LZ803B; for the base oil 150SN, the pour point depressant after compounding The pour point depressant can reduce the maximum temperature by 32°C, surpassing the effect of industrial poly-α-olefin pour point depressant LZ803B.

Claims (9)

1. terpolymer is as the application of pour depressant for lubricating oil, it is characterized in that, the structural formula of described terpolymer is as follows:

In formula, n is the integer of 7-17, and a, b, c are respectively the integer of 1-1000, and the viscosity-average molecular weight of terpolymer is 10000-500000;

Described terpolymer is prepared by following methods:

(1) in device, add the senior ester of fumaric acid, vinyl acetate and vinylbenzene, wherein, the senior ester of fumaric acid, vinyl acetate and cinnamic molar fraction are respectively 10-80%;

(2) radical polymerization initiator that consumption is the 0.1-1% of the senior ester of fumaric acid, vinyl acetate and vinylbenzene total mass is added;

(3) 70-80 DEG C is warming up to, reaction 3-8 hour;

(4) underpressure distillation, removes excessive vinyl acetate, obtains terpolymer;

The structural formula of the senior ester of described fumaric acid is in formula, n is the integer of 7-17.

2. terpolymer according to claim 1 is as the application of pour depressant for lubricating oil, it is characterized in that, described n is the integer of 11-15.

3. terpolymer according to claim 1 is as the application of pour depressant for lubricating oil, it is characterized in that, described viscosity-average molecular weight is 20000-40000.

4. terpolymer according to claim 1 is as the application of pour depressant for lubricating oil, it is characterized in that, described pour point depressant is the mixture of multiple described terpolymer.

5. terpolymer according to claim 1 is as the application of pour depressant for lubricating oil, it is characterized in that, described pour point depressant to be n be 11 terpolymer and n be the mixture of the terpolymer 1:1-7:3 mixing in mass ratio of 13.

6. terpolymer according to claim 1 is as the application of pour depressant for lubricating oil, it is characterized in that, the senior ester of described fumaric acid, vinyl acetate and cinnamic molar fraction are respectively 20-60%.

7. terpolymer according to claim 1 is as the application of pour depressant for lubricating oil, it is characterized in that, the consumption of described radical polymerization initiator is 0.5% of the senior ester of fumaric acid, vinyl acetate and vinylbenzene total mass.

8. terpolymer according to claim 1 is as the application of pour depressant for lubricating oil, it is characterized in that, described radical polymerization initiator is dibenzoyl peroxide or Diisopropyl azodicarboxylate.

9. terpolymer according to claim 1 is as the application of pour depressant for lubricating oil, it is characterized in that, the described reaction times is 4-6 hour.