CN112625316A - Oil gel and preparation method and application thereof - Google Patents

Abstract

The invention discloses an oleogel and a preparation method and application thereof. Aiming at the current situation that the existing organic photothermal conversion material in the market is a conjugated organic material, the invention aims to provide the iodine-doped rubber oleogel to realize the characteristic of easy processing of the photothermal conversion material. It is obtained by the following method: the rubber is dissolved in an organic solvent and doped by adding a certain amount of iodine to obtain an iodine doped rubber-based oil gel. The material has no rigidity of a conjugated structure, is easy to process, can be processed by injection molding, and can be coated on various substrates to realize the endowment of photo-thermal conversion performance.

Description

Oil gel and preparation method and application thereof

Technical Field

The invention relates to the field of materials, and relates to an oleogel, and a preparation method and application thereof.

Background

The development of technology depends on the development and utilization of new energy, while the sustainable development of human society depends on the effective utilization of clean energy. Therefore, the development and utilization of clean new energy is a necessary choice for the development and progress of the human society. Under the development of a plurality of sustainable clean energy sources, solar energy plays an increasingly important role in production and life as a novel energy source technology widely existing in the nature. The utilization mode of converting light into heat greatly enriches the application scene of light energy, improves the application range and efficiency of the light energy, and plays a significant role in the fields of seawater desalination, analysis and detection, cancer diagnosis and treatment and the like. At present, the key and difficulty of the research in the field of photothermal conversion is that the preparation method of photothermal conversion materials is complex, the heat resistance of the materials is poor, and at the same time, many photothermal materials can only utilize a certain section of the solar spectrum, so that the key problem can be solved more effectively by developing a wide-spectrum absorption photothermal conversion material in order to better utilize sunlight.

Currently, inorganic photothermal conversion materials include carbon-based, metal-based, and semiconductor-based photothermal conversion materials. The carbon-based photothermal conversion material is most widely applied, but the carbon-based photothermal conversion material can only be applied to the low-temperature field (below 200 ℃) of a solar water heater and the like due to several defects, and firstly, the inorganic material needs to be loaded with other materials in the actual application process, so that the better performance and the forming processing are realized, and the production and preparation process is more complicated. Secondly, the inorganic photothermal conversion material is easily oxidized and decomposed in a high-temperature environment, so that the performance of the photothermal material is reduced and even loses efficacy. Third, some inorganic photothermal materials such as chalcogen copper-based or transition metal oxide type semiconductor photothermal materials are difficult to degrade and have low long-term stability due to the heavy metal elements contained therein. In addition, the inorganic photothermal conversion material is difficult to mass produce in large scale, and the molding processability is poor, and these problems together restrict the further development and application of the inorganic photothermal conversion material. The organic photothermal conversion material is mostly concentrated on polymers represented by conjugated polymers. Relying on a long conjugated structure generally leads to a lower transition energy level, which in turn leads to a greater degree of nonradiative transition after absorption of optical energy and thus to more heat generation. However, compared with the electrodeless photo-thermal material, the organic conjugated polymer has strong intermolecular acting force, cannot be molded and processed on a large scale at all, can be prepared only on a small scale and in a small size in a solvent or high-temperature mode, and meanwhile, the organic material is difficult to bear high temperature, so that the organic material does not exist in the solar photo-thermal market at present. Rubber is widely applied to the industrial and living fields as a material with simple and convenient processing, low price and excellent performance, but the modification of the rubber at present can be applied to various special environments generally through functional doping, and no document is provided for preparing the rubber into gel and researching the performance of the gel.

Disclosure of Invention

The invention aims to provide an oleogel and a preparation method and application thereof.

The invention provides a method for preparing oil gel, which comprises the following steps:

1) dissolving rubber in an organic solvent, and then adding iodine for dissolving to obtain a photo-thermal precursor;

2) and curing and molding the photo-thermal precursor, volatilizing the solvent, and carrying out hot stage treatment to obtain the oleogel.

In the method, the rubber is an industrial grade rubber raw material; specifically at least one selected from trans-polyisoprene, natural rubber, cis-polyisoprene, styrene-butadiene-styrene block copolymer (SBS) and styrene-butadiene rubber (SBR);

the organic solvent is selected from at least one of alkanes of C1-C6, alkenes of C2-C10, alcohols of C1-C20, aldehydes of C1-C20, acids, esters of C1-C40, ethers of C1-C100, ketones of C1-C100, aromatic hydrocarbons, hydrogenated hydrocarbons, terpene hydrocarbons, halogenated hydrocarbons, heterocyclic compounds, nitrogen-containing compounds and sulfur-containing compounds;

specifically, the solvent is at least one selected from chloroform, dichloromethane, ethanol, tetrahydrofuran, dimethyl sulfoxide, toluene, xylene, pentane, hexane, octane, cyclohexane, cyclohexanone, toluene cyclohexanone, diethyl ether, acetone and acetonitrile.

In the step 1), the dosage ratio of the rubber to the organic solvent is 0.01-20 g: 100 mL; specifically, 5 g: 100 mL;

the molar ratio of the rubber to the iodine is 1-10: 1; specifically 1-2:1 or 4-5: 1;

in the dissolving step, the temperature is 0-180 ℃; specifically 50 ℃.

In the step 2), in the step of curing and forming, the temperature is 0-180 ℃; in particular 80 ℃;

in the step of heat stage treatment, the temperature is 50-350 ℃; in particular 150 ℃; the time is 0.5 to 48 hours; specifically 0.5-24 h; in particular 4 h. The purpose of this step is to remove unbound elemental iodine.

In addition, the oil gel prepared by the method and the photo-thermal coating prepared from the oil gel also belong to the protection scope of the invention.

The thickness of the photo-thermal coating is 20-80 microns, and specifically can be 30 microns.

The invention provides a method for preparing the photo-thermal coating, which comprises the following steps: the oil gel is coated on the surface of a metal substrate.

In the above method, the substrate is iron, aluminum or an alloy thereof;

the coating method is spraying, brushing or leveling;

the dosage of the oil gel is 200-2000g per square meter; specifically 400g per square meter.

In addition, the application of the photothermal coating provided by the invention in photothermal conversion and the application in preparing photothermal conversion products also belong to the protection scope of the invention.

The invention provides a method for synthesizing oleogel based on iodine-doped rubber, which is applied to the field of photo-thermal conversion, solves the problems in the preparation process of photo-thermal conversion materials and is applied to actual production and life. The method is expected to provide a new thought for processing rubber and preparing oleogel, and provides a new preparation method for the organic photothermal conversion material.

The oil gel provided by the invention has the following advantages:

(1) the raw materials of the oil gel prepared by the method are cheap and easy to obtain, the preparation method is simple, the required process equipment is few, and only stirring and dissolving are needed;

(1) the organic black gel prepared by the method has the advantages of simple preparation mode, less required process equipment, homogeneous reaction, no phase separation, intrinsic black characteristic, suitability for large-scale production of a chemical plant in a new era and suitability for various application scenes.

(2) The method has the advantages that the reaction process of the obtained oil gel can be regulated and controlled according to the amount of iodine added in the reaction and the temperature in the reaction, so that the performance of the oil gel is regulated and controlled.

(3) The oil gel prepared by the method has excellent photo-thermal conversion performance, and can realize the photo-thermal conversion performance by being coated and supported on different substrates.

(4) The oil gel obtained in the application has high thermal stability, and can realize the excellent photo-thermal conversion repeatability without attenuation under multiple cycles. And the practical application requirements are met.

Drawings

FIG. 1 shows that different shapes of oil gel are obtained by injection molding of different molds.

FIG. 2 shows the thermal stability of an oil gel by thermogravimetric analysis.

FIG. 3 shows the photothermal conversion performance of the oleogel under different light powers with 808nm and 1064nm light source irradiation.

FIG. 4 shows the photothermal conversion stability of the oleogel under 808nm and 1064nm light source irradiation.

Detailed Description

The present invention will be further illustrated with reference to the following specific examples, but the present invention is not limited to the following examples. The method is a conventional method unless otherwise specified. The starting materials are commercially available from the open literature unless otherwise specified.

Examples 1,

Preparing a styrene-butadiene-styrene doped iodized oil gel block material;

the oil gel is prepared from the following raw materials: styrene-butadiene-styrene block copolymer (SBS), chloroform, iodine;

the preparation method comprises the following steps:

styrene-butadiene-styrene block copolymer (SBS) was dissolved in chloroform at 5% mass volume (i.e. the amount ratio of rubber to chloroform was 5 g: 100mL) and was dissolved thoroughly. Subsequently adding iodine to the mixture, wherein the ratio of iodine to styrene-butadiene-styrene is 1: 2, adding magnetons, and continuously stirring and dissolving at 50 ℃ to fully contact and react. And (3) gradually thickening the solution, pouring the viscous solution into a mould, and curing and molding at 80 ℃ to prepare black block materials with different shapes. And then volatilizing the trichloromethane at room temperature, and further volatilizing the trichloromethane for 4 hours at the temperature of 150 ℃ by hot stage treatment to obtain the oleogel provided by the invention.

Example 2:

examples 2-5 the same procedure as in example 1 was followed, with the molar ratio of rubber to iodine being adjusted to 1: 0. 10: 1,5: 1,4: 1,1: 1.

the properties of the mixture obtained in the above experiment are shown in table 1: it is known that the oleogel cannot be crosslinked without the presence of iodine; when the ratio of rubber to iodine is 1: 1 to 1: 2, too small amount of iodine will slow the reaction and is not favorable for the subsequent experiment.

TABLE 1 Properties of the mixed solvents obtained in different proportions

Examples 6-10 the same procedure as in example 1 was followed, with the organic solvent replaced with dichloromethane, tetrahydrofuran, toluene, dioxane, cyclohexane: the gelling property is not very different, and the later curing time is influenced, so that the organic solvent or the mixed solution thereof can be used.

Example 11:

preparing styrene-butadiene-styrene doped iodized oil gel coating, wherein the oil gel is prepared from the following raw materials: styrene-butadiene-styrene, chloroform, iodine; the preparation method comprises the following steps: styrene-butadiene-styrene was dissolved in chloroform at 5% by mass volume and sufficiently dissolved. Subsequently adding iodine into the rubber, wherein the molar ratio of the iodine to the rubber is 2: and 1, adding a magnet and stirring continuously to ensure that the mixture is fully contacted and reacted. The solution gradually became viscous, at which time the solution was spread on the bottom of a commercially available autoclave and evenly spread.

The difference from example 1 above is that the application here is based on oleogel photothermal coating.

Example 12: thermal stability analysis of oil gel bulk Material in example 1

And measuring the relation between the mass of the sample to be measured and the temperature change by using a thermogravimetric analyzer at the program control temperature. The temperature rise rate was set at 10 ℃/min, and the difference in thermal stability was compared from room temperature to 600 ℃.

Experimental results as shown in fig. 2, the oleogel exhibited stability in excess of 350 degrees celsius after two hours of treatment at 250 degrees celsius.

Example 13: photo-thermal conversion test of oil gel bulk materials in example 1

And collecting the sheet photothermal conversion temperature rise data under 808nm and 1064nm laser irradiation by using a Fluke Tix 660 infrared camera. The obtained temperature rise condition is related to the power of the light source, and the specific experimental process and results are as follows:

the room temperature is controlled to be 25 ℃ in the photothermal conversion test, and different powers (0.1, 0.3, 0.5, 0.7, 0.9 and 1.1W/cm) are respectively used for 808nm light sources and 1064nm light sources²) And testing the photo-thermal conversion temperature rise condition of the oil gel block material under irradiation. The irradiation time was set to 3min, the cooling time was 3min, 3 cycles of testing were performed, and the final temperature rise was recorded.

The experimental results are shown in fig. 3, which records the final temperature rise of styrene-butadiene-styrene after irradiation for 3min with different infrared powers. At a power of 0.1W/cm²After irradiation for 3min, the surface temperature can reach 34 ℃ (808nm), and the temperature can reach 28 ℃ under the illumination of 1064 nm; while increasing the power at 0.9W/cm²The surface temperature of the oil gel is over 200 ℃ under the irradiation of light sources with 1064nm and 808nm, and the power is 1.1W/cm²After the surface of the oil gel is irradiated for 3min under the optical power, the surface temperature of the oil gel can reach more than 220 ℃.

Example 14: test of photothermal conversion stability of oil gel bulk Material in example 1

Collecting laser beam at 808nm and 1064nm at 0.9W/cm by Fluke Tix 660 infrared camera²And (3) photo-thermal conversion heating data of the oil gel block material under irradiation. The temperature rise obtainedThe situation is related to the power of the light source, and the specific experimental process and results are as follows:

the room temperature is controlled to be 25 ℃ in the photothermal conversion test, and the light sources at 808nm and 1064nm are controlled to be 0.7W/cm²The photo-thermal conversion temperature rise condition of the oil gel block material is tested under the irradiation of the optical power. Setting the irradiation time to be 3min, setting the cooling time to be 3min, testing 20 cycles, and recording the temperature change condition in the process.

The experimental results are shown in fig. 3, and it is recorded that after 20 cycles of irradiation and cooling with different infrared powers, the temperature is stabilized above 200 ℃, and the temperature changes steadily, and no significant decrease in photothermal conversion performance is observed.

Claims (10)

1. A method of making an oleogel comprising:

1) dissolving rubber in an organic solvent, and then adding iodine for dissolving to obtain a photo-thermal precursor;

2) and curing and molding the photo-thermal precursor, volatilizing the solvent, and carrying out hot stage treatment to obtain the oleogel.

2. The method of claim 1, wherein: the rubber is an industrial rubber raw material; specifically at least one selected from trans-polyisoprene, natural rubber, cis-polyisoprene, styrene-butadiene-styrene block copolymer (SBS) and styrene-butadiene rubber (SBR);

the organic solvent is selected from at least one of alkanes of C1-C6, alkenes of C2-C10, alcohols of C1-C20, aldehydes of C1-C20, acids, esters of C1-C40, ethers of C1-C100, ketones of C1-C100, aromatic hydrocarbons, hydrogenated hydrocarbons, terpene hydrocarbons, halogenated hydrocarbons, heterocyclic compounds, nitrogen-containing compounds and sulfur-containing compounds;

specifically, the solvent is at least one selected from chloroform, dichloromethane, ethanol, tetrahydrofuran, dimethyl sulfoxide, toluene, xylene, pentane, hexane, octane, cyclohexane, cyclohexanone, toluene cyclohexanone, diethyl ether, acetone and acetonitrile.

3. The method according to claim 1 or 2, characterized in that: in the step 1), the dosage ratio of the rubber to the organic solvent is 0.01-20 g: 100 mL; specifically, 5 g: 100 mL;

the molar ratio of the rubber to the iodine is 1-10: 1; specifically 2: 1;

in the dissolving step, the temperature is 0-180 ℃.

4. A method according to any one of claims 1 to 3, wherein: in the step 2), in the step of curing and forming, the temperature is 0-180 ℃;

in the step of heat stage treatment, the temperature is 50-350 ℃; the time is 0.5 to 48 hours; in particular 0.5-24 h.

5. An oleogel prepared by the process of any of claims 1-4.

6. Photothermal coatings prepared from the oleogel of claim 5.

7. A method of preparing the photothermal coating of claim 6 comprising: the oleogel of claim 6 applied to the surface of a metal substrate.

8. The method of claim 7, wherein: the substrate is iron, aluminum or alloy thereof;

the coating method is spraying, brushing or leveling;

the dosage of the oil gel is 200-2000g per square meter; specifically 400g per square meter.

9. Use of the photothermal coating of claim 6 in photothermal conversion.

10. Use of the photothermal coating of claim 6 for the preparation of a photothermal conversion product.

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