CN115368222A

CN115368222A - Modified cashew nut oil, cashew nut oil rubber plasticizer, and preparation method and application thereof

Info

Publication number: CN115368222A
Application number: CN202210987087.0A
Authority: CN
Inventors: 李海辉; 徐黎明; 彭华龙; 姚翔
Original assignee: Jiangsu Cheeshine Performance Materials Co ltd
Current assignee: Jiangsu Cheeshine Performance Materials Co ltd
Priority date: 2022-08-17
Filing date: 2022-08-17
Publication date: 2022-11-22
Also published as: WO2024036924A1

Abstract

The invention discloses modified cashew nut oil, cashew nut oil rubber plasticizer, and a preparation method and application thereof. The cashew nut oil is chemically modified, phenolic hydroxyl in the cashew nut oil is converted into alcoholic hydroxyl, and the cashew nut oil rubber plasticizer is prepared, so that the problems of toxic hazard of harmful components of a petroleum plasticizer to human bodies and pollution to the environment are solved, the compatibility of the cashew nut oil rubber plasticizer with inorganic fillers can be improved in a rubber composition, the Mooney viscosity is obviously reduced, and the processability and the mechanical property of the rubber composition are enhanced.

Description

Modified cashew nut oil, cashew nut oil rubber plasticizer, and preparation method and application thereof

Technical Field

The invention belongs to the technical field of rubber industry, and particularly relates to modified cashew nut oil, a cashew nut oil rubber plasticizer, and a preparation method and application thereof.

Background

The rubber plasticizer is a processing aid commonly used in rubber production, and can improve the processability, mechanical property and dynamic mechanical property of rubber. China is the largest plasticizer production, consumption and import market in the world, and petroleum plasticizers have an absolute leading position. Nowadays, petroleum chemicals face problems such as price rise and shortage of raw materials, and toxicity to human bodies and pollution to the environment are also generally concerned by international society, so that vegetable oil substitutes such as cashew nut oil, soybean oil and palm oil, which are bio-based chemicals with wide sources, low pollution and low toxicity and can be regenerated, are gradually becoming the development trend of the plasticizer industry in the future.

Cashew nut oil (CNSL), an agricultural byproduct in cashew nut processing, accounts for 25% -30% of cashew nuts, has annual output of about 50 ten thousand tons all over the world, and is a renewable resource with low price and wide source. However, cashew nut oil has significant drawbacks when used as a rubber plasticizer: some of the application properties of the compound are poor, including too short a scorch time, too low a stress at definite elongation, too poor wet skid resistance, etc. Therefore, it is necessary to modify cashew nut oil by chemical means to improve the compatibility of rubber and inorganic filler, and further to impart good processability, mechanical properties or (and) dynamic mechanical properties to rubber.

Disclosure of Invention

In order to overcome the defects of the prior art, the invention provides modified cashew nut oil, a cashew nut oil rubber plasticizer, and a preparation method and application thereof. The aim is to chemically modify cashew nut oil to form a cashew nut oil rubber plasticizer, which not only overcomes the problems of toxic hazard of harmful components of petroleum plasticizers to human bodies and pollution to the environment, but also improves the compatibility of the cashew nut oil rubber plasticizer with inorganic fillers in rubber compositions, obviously reduces the Mooney viscosity, and enhances the processability and mechanical properties of the rubber compositions.

The method is realized by the following technical scheme:

a modified cashew nut oil comprising the following structural formula:

wherein R is ₁ Is H, OH or

R ₂ Is H or CH ₃ When R is ₁ When is H, R ₂ Is not CH ₃ ，R ₃ Is H or CH ₃ ，R ₄ Is H or CH ₃ And n is 0, 2, 4 or 6.

The invention converts the phenolic hydroxyl of the cashew nut oil into alcoholic hydroxyl, improves the compatibility of the cashew nut oil with inorganic filler by providing one or more alcoholic hydroxyl in a chemical structure, obviously improves scorching and enhances the processing safety of rubber materials.

The cashew nut oil rubber plasticizer is the modified cashew nut oil.

The invention also provides a preparation method of the modified cashew nut oil or cashew nut oil rubber plasticizer, which comprises the following steps:

mixing cashew nut oil with cyclic carbonate, adding a catalyst, and reacting at a certain temperature to obtain the modified cashew nut oil or the cashew nut oil rubber plasticizer.

Further, the cashew nut oil is one or more of Cardanol (Cardanol), cardic acid (Cardol) and 2-Methyl Cardol. The structural formula is shown as formula (1).

Further, the cyclic carbonate is one or more of ethylene carbonate, propylene carbonate and butylene carbonate.

Further, the catalyst is one or more of tetrabutylammonium fluoride, tetrabutylammonium chloride, tetrabutylammonium bromide, tetrabutylammonium iodide, tetrabutylammonium chloride monohydrate, tetrabutylammonium fluoride trihydrate, tetrabutylammonium hydroxide 30 hydrate, benzyltriethylammonium chloride, tetrabutylammonium hydrogen sulfate, trioctylmethylammonium chloride, dodecyltrimethylammonium chloride and tetradecyltrimethylammonium chloride.

Further, the temperature of the reaction is 140 to 200 ℃, preferably 160 to 180 ℃. The reaction efficiency is too low when the temperature is lower than 140 ℃, and more side reactions occur when the temperature is higher than 200 ℃.

Further, the reaction time period is 1 to 5 hours, preferably 2 to 4 hours. If the reaction time is less than 1 hour, the conversion of cyclic carbonate is too low, and if it is more than 5 hours, side reactions gradually increase.

Further, the dosage of the cyclic carbonate is 0-30% of the weight of the cashew nut oil.

Further, the dosage of the catalyst is 0.2-1.0% of the weight of the cashew nut oil.

A plasticizer, which comprises the cashew nut oil rubber plasticizer.

Further, the plasticizer can be a mixture of the cashew nut oil rubber plasticizer and naphthenic oil and/or environment-friendly aromatic oil. Wherein the weight ratio of the cashew nut oil rubber plasticizer to the naphthenic oil and/or the environment-friendly aromatic oil is 0.1.

The invention also provides application of the modified cashew nut oil or cashew nut oil rubber plasticizer in tire rubber processing.

Compared with the prior art, the invention has the following advantages:

1. the good rubber plasticizer has the characteristics of large plasticizing effect, small using amount and the like, and the modified cashew nut oil or cashew nut oil rubber plasticizer or plasticizer provided by the invention can obviously improve scorching and enhance the processing safety of rubber materials; the Mooney viscosity is obviously reduced under the condition of decrement, the softening force is strong, the difficulty of processing technologies such as mixing, calendering, extruding, injecting, mould pressing and vulcanizing of rubber materials can be reduced, the industrial energy consumption is reduced, the rubber material mixing time is shortened, the production efficiency is improved, the process cost is saved, and meanwhile, the vulcanized rubber has good application performance.

2. The plasticizer is prepared from vegetable oil serving as a raw material, is low in cost, small in pollution, low in toxicity and renewable, realizes environmental protection of the plasticizer, contains no polycyclic aromatic hydrocarbon, is simple in preparation process, is environment-friendly, is beneficial to industrial popularization, and overcomes the problems of toxicity to human bodies and pollution to the environment of petroleum plasticizers.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the description below are only some embodiments of the present application, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.

FIG. 1 is a nuclear magnetic hydrogen spectrum of cashew nut oil rubber plasticizer 3 in example 3;

FIG. 2 is a nuclear magnetic hydrogen spectrum of comparative example 2.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be obtained by a person skilled in the art without making any creative effort based on the embodiments in the present invention, belong to the protection scope of the present invention.

Specification and source of raw materials:

cashew nut oil: industrial grade, high tech. chemical university;

butylene carbonate: 99% of alatin;

tetrabutylammonium bromide: 99.5%, annaiji chemical;

propylene carbonate: 99% of alatin;

tetrabutylammonium iodide: 99.5%, annaiji chemical;

ethylene carbonate: 99% of alatin;

tetrabenzyltriethylammonium chloride: 99.5%, annaiji chemical;

naphthenic oil: n2, sky source chemical limited;

environmental protection aromatic oil TDAE: VIVATEC500, hansan chemical limited.

Example 1

Adding 300g of cashew nut oil and 30g of butylene carbonate into a flask, and uniformly mixing and stirring; then 0.6g of tetrabutylammonium bromide is added into the flask, and the mixture is stirred for 2 hours after the temperature is raised to 150 ℃; the unreacted ethylene carbonate was distilled off under reduced pressure to obtain cashew nut oil rubber plasticizer 1 (abbreviated as plasticizer 1 in table 2).

Example 2

Adding 300g of cashew nut oil and 60g of propylene carbonate into a flask, and uniformly mixing and stirring; adding 1.5g of tetrabutylammonium iodide into the flask, heating to 170 ℃, and stirring for 3 hours; the unreacted ethylene carbonate was distilled off under reduced pressure to obtain cashew nut oil rubber plasticizer 2 (abbreviated as plasticizer 2 in table 2).

Example 3

Adding 300g of cashew nut oil and 90g of ethylene carbonate into a flask, and uniformly mixing and stirring; adding 3g of tetrabenzyltriethyl ammonium chloride into the flask, heating to 190 ℃, and stirring for 4 hours; the unreacted ethylene carbonate was distilled off under reduced pressure to obtain cashew nut oil rubber plasticizer 3 (abbreviated as plasticizer 3 in table 2).

Example 4

And mixing the cashew nut oil rubber plasticizer 3 with naphthenic oil according to the mass ratio of 3.

Example 5

And mixing the cashew nut oil rubber plasticizer 3 with naphthenic oil according to a mass ratio of 7.

Example 6

And mixing the cashew nut oil rubber plasticizer 3 with the environment-friendly aromatic oil TDAE in a mass ratio of 3.

Example 7

And mixing the cashew nut oil rubber plasticizer 3 with the environment-friendly aromatic oil TDAE in a mass ratio of 7.

Comparative example 1

Environment protection aromatic oil (TDAE)

Comparative example 2

Naphthenic oil

Comparative example 3

Cashew nut oil

< Nuclear magnetic Hydrogen Spectroscopy test >

FIG. 1 is a nuclear magnetic hydrogen spectrum of cashew nut oil rubber plasticizer 3 in example 3, FIG. 2 is a nuclear magnetic hydrogen spectrum of comparative example 2, and it can be known from nuclear magnetic hydrogen spectrum test that cashew nut oil before reaction has an obvious peak of phenolic hydroxyl at 9.15ppm, the signal of cashew nut oil rubber plasticizer 3 obtained after reaction at 9.15ppm has completely disappeared, and a new signal peak appears at 3.92-4.03 ppm, that is, the newly generated-CH ₂ CH ₂ Signal peak of methylene hydrogen on OH. Since the reaction principle of examples 1 and 2 is similar to that of example 3 and the preparation process is also similar, the nuclear magnetic hydrogen spectra of examples 1 and 2 are similar to that of example 3, and only slight differences of individual substituents exist.

< polycyclic aromatic hydrocarbons test >

Polycyclic aromatic hydrocarbon testing was performed on the cashew oil rubber plasticizers of examples 1-3, and the results are shown in Table 1.

Table 1.

According to AfPS (German product safety Committee) and the European Union for polycyclic aromatic hydrocarbons, baP means that the content of benzo (a) pyrene should be less than 1ppm,8 and less than 10ppm. Item 8 and means: the total content of eight items including benzo (a) anthracene + chrysene + benzo (b) fluoranthene + benzo (k) fluoranthene + benzo (j) fluoranthene + benzo (e) pyrene + benzo (a) pyrene + dibenzo (a, h) anthracene. According to test results, the cashew nut oil rubber plasticizer provided by the invention meets the specification.

< processability and mechanical Properties test of Tread rubber composition >

Table 2.

Rubber compositions were prepared according to the formulation shown in Table 2, and the Mooney viscosity and other various application properties of the rubber compositions were measured, and the results are shown in tables 3 and 4.

Table 3.

Table 4.

From the above test results, it can be seen that:

(1) From the comparison of the rubber compositions O1, O2, A, B and C, it can be seen that the cashew nut oil rubber plasticizer 1, 2 and 3 obtained by chemical modification significantly reduced the Mooney viscosity of the rubber compositions, and that in the case of using 26.6phr of the plasticizer, the Mooney viscosity of the cashew nut oil rubber plasticizer 3 was 20% lower than that of 26.6phr of naphthenic oil and 25% lower than that of 38.0phr of TDAE.

(2) The rubber composition O3 can be used for obtaining that the cashew nut oil has obvious defects when being used as a plasticizer, including short scorching time, low stress at definite elongation and the like, the cashew nut oil rubber plasticizers 1, 2 and 3 obtained by chemical modification overcome the defects, and the corresponding rubber compositions A, B and C have longer scorching time and higher stress at definite elongation;

(3) The rubber compositions D, E, F and G use the composite plasticizer formed by mixing the naphthenic oil, TDAE and cashew oil rubber plasticizer, and the comprehensive performance of the rubber compositions D, E, F and G also shows a certain advantage that the raw material cost is saved while the performance is improved.

In conclusion, the cashew nut oil is modified to prepare the cashew nut oil rubber plasticizer, the problems of poison of harmful components of petroleum plasticizers to human bodies and pollution to the environment are solved, the phenolic hydroxyl group rich in the cashew nut oil is converted into the alcoholic hydroxyl group by a chemical means, the compatibility of the cashew nut oil rubber plasticizer with inorganic fillers is improved in a rubber composition, the Mooney viscosity is obviously reduced, the difficulty of processing technologies such as mixing, calendaring, extruding, injecting, mould pressing and vulcanizing of rubber materials is reduced, the industrial energy consumption is reduced, the production efficiency is improved, the process cost is saved, and meanwhile, the vulcanized rubber is endowed with good application performance.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and should not be taken as limiting the scope of the present invention, which is intended to cover any modifications, equivalents, improvements, etc. within the spirit and scope of the present invention.

Claims

1. A modified cashew nut oil characterized by the following structural formula:

wherein R is ₁ Is H, OH or

R ₂ Is H or CH ₃ (ii) a When R is ₁ When is H, R ₂ Is not CH ₃ ；R ₃ Is H or CH ₃ ；R ₄ Is H or CH ₃ (ii) a n is 0, 2, 4 or 6.

2. A cashew oil rubber plasticizer characterized in that said cashew oil rubber plasticizer comprises the modified cashew oil of claim 1.

3. The method of preparing the modified cashew nut oil of claim 1 or the method of preparing the cashew nut oil rubber plasticizer of claim 2, comprising the steps of:

mixing cashew nut oil with cyclic carbonate, adding a catalyst, and reacting to obtain the modified cashew nut oil or the cashew nut oil rubber plasticizer.

4. The preparation method according to claim 3, wherein the cashew nut oil is one or more of cardanol, strong heart acid, and 2-methyl strong heart acid.

5. The method according to claim 3, wherein the cyclic carbonate is one or more of ethylene carbonate, propylene carbonate, and butylene carbonate.

6. The method of claim 3, wherein the catalyst is one or more of tetrabutylammonium fluoride, tetrabutylammonium chloride, tetrabutylammonium bromide, tetrabutylammonium iodide, tetrabutylammonium chloride monohydrate, tetrabutylammonium fluoride trihydrate, tetrabutylammonium hydroxide 30 hydrate, benzyltriethylammonium chloride, tetrabutylammonium hydrogen sulfate, trioctylmethylammonium chloride, dodecyltrimethylammonium chloride, and tetradecyltrimethylammonium chloride.

7. The method of claim 3, wherein the reaction temperature is 150 to 190 ℃.

8. The method of claim 3, wherein the reaction time is 2 to 4 hours.

9. The preparation method according to claim 3, wherein the amount of the cyclic carbonate is 0.1-30% by mass of the cashew nut oil.

10. The preparation method according to claim 3, wherein the catalyst is used in an amount of 0.2 to 1.0% by mass based on the cashew nut oil.

11. A plasticizer comprising the cashew nut oil rubber plasticizer of claim 2.

12. Use of any one of the modified cashew oil of claim 1, the cashew oil rubber plasticizer of claim 2, and the plasticizer of claim 11 in the processing of tire rubber.