阅读说明：本技术 一种荧光溶解氧传感器膜片及其制备方法 (Fluorescent dissolved oxygen sensor diaphragm and preparation method thereof ) 是由 王红璐 罗艳 刘海波 边宝丽 华亚军 赵有朋 张玉珍 戴俏俏 曹芮 李丹 于 2019-09-19 设计创作，主要内容包括：本发明提供荧光溶解氧传感器膜片的制备方法,所述方法包括：将聚氯乙烯粉、邻苯二甲酸二异辛脂和四氢呋喃按5g：8g：100ml混合,在超声机中超声混合均匀,在所述载体基片的中心区域上丝网印刷成膜,烘干；将负载有荧光指示剂的固体颗粒、萘酚和有机易挥发溶剂按1g：1ml：100ml混合,超声分散均匀,超声波喷涂在所述透明层表面,烘干；将聚二甲基硅氧烷、正硅酸乙酯、二月桂酸二丁基锡、曲拉通X-100、炭黑以20:4:1:1:1质量比例均匀混合后,丝网印刷涂覆于荧光层表面,烘干；将金属粉末、萘酚超声和甲苯按1g:1ml：200ml均匀混合,将其超声波喷涂在荧光保护层表面,烘干。本发明提供的荧光溶解氧传感器膜片及其制备方法,可改善荧光膜材料的荧光特性、稳定性和加工性。(The invention provides a preparation method of a fluorescent dissolved oxygen sensor diaphragm, which comprises the following steps: mixing polyvinyl chloride powder, diisooctyl phthalate and tetrahydrofuran according to the weight ratio of 5 g: 8 g: 100ml of the mixture is mixed, the mixture is evenly mixed by ultrasonic in an ultrasonic machine, and the film is formed on the central area of the carrier substrate by silk-screen printing and dried; solid particles loaded with a fluorescent indicator, naphthol and an organic volatile solvent are mixed according to the weight ratio of 1g:1 ml: 100ml of the mixture is mixed, uniformly dispersed by ultrasonic waves, sprayed on the surface of the transparent layer by ultrasonic waves and dried; uniformly mixing polydimethylsiloxane, ethyl orthosilicate, dibutyltin dilaurate, Triton X-100 and carbon black in a mass ratio of 20:4:1:1:1, then coating the mixture on the surface of a fluorescent layer by screen printing, and drying; metal powder, naphthol ultrasonic and toluene were mixed in a ratio of 1g:1 ml: 200ml of the mixture is evenly mixed, and the mixture is sprayed on the surface of the fluorescent protective layer by ultrasonic waves and dried. The fluorescent dissolved oxygen sensor membrane and the preparation method thereof provided by the invention can improve the fluorescence characteristic, stability and processability of the fluorescent membrane material.)

1. A preparation method of a fluorescent dissolved oxygen sensor diaphragm is characterized by comprising the following steps:

1) mixing polyvinyl chloride powder, diisooctyl phthalate and tetrahydrofuran according to the weight ratio of 5 g: 8 g: 100ml of the mixture is mixed, the mixture is evenly mixed by ultrasound in an ultrasonic machine, a film is formed on the central area of the carrier substrate by silk-screen printing, and a transparent layer is formed by drying;

2) solid particles loaded with a fluorescent indicator, naphthol and an organic volatile solvent are mixed according to the weight ratio of 1g:1 ml: 100ml of the mixture is mixed, uniformly dispersed by ultrasonic waves, sprayed on the surface of the transparent layer by ultrasonic waves, and dried to form a fluorescent layer;

3) uniformly mixing polydimethylsiloxane, ethyl orthosilicate, dibutyltin dilaurate, Triton X-100 and carbon black in a mass ratio of 20:4:1:1:1, then coating the mixture on the surface of a fluorescent layer by screen printing, and drying to form a fluorescent protection layer;

4) metal powder, naphthol ultrasonic and toluene were mixed in a ratio of 1g:1 ml: 200ml of the mixture is uniformly mixed, and the mixture is sprayed on the surface of the fluorescent protective layer by ultrasonic waves and dried to form a metal protective layer.

2. The method of claim 1, further comprising treating the carrier substrate prior to preparation by: the carrier substrate with the diameter of 3 cm and the thickness of 1 mm is soaked in 1mol/L sodium hydroxide and sulfuric acid for 2-6 hours respectively, and finally washed by absolute ethyl alcohol and dried.

3. The method for preparing the fluorescent dissolved oxygen sensor diaphragm according to claim 1, wherein the material of the carrier substrate in the step 1) is quartz glass, sapphire or organic glass with the light transmittance of more than 90%.

4. The method for preparing a fluorescent dissolved oxygen sensor membrane according to claim 1, wherein the thickness of the transparent layer in step 1) is 30-120 μm.

5. The method for preparing a fluorescence dissolved oxygen sensor membrane according to claim 1, wherein the fluorescence indicator in step 2) is Ru (dpp) capable of being excited by visible light₃ ²⁺、Ru(bpy)₃ ²⁺Or Ru (OEP) ruthenium polypyridine complexes and PtOEP, PtOEPK or PtTFPP platinum porphyrin complexes; the solid particles can be at least one of organic resin powder, organic silicon rubber particles or nano silicon dioxide; the mass fraction of the solid particle loaded fluorescent indicator is 0.1-3%.

6. The method for preparing a fluorescent dissolved oxygen sensor membrane according to claim 1, wherein the particle size of the solid particles in step 2) is 10-200 nm; the thickness of the fluorescent layer is 0.5-20 microns.

7. The method for preparing the fluorescent dissolved oxygen sensor membrane as claimed in claim 1, wherein the thickness of the fluorescent protective layer in step 3) is 60-150 μm.

8. The method for preparing a fluorescence dissolved oxygen sensor membrane according to claim 1, wherein the metal powder in step 4) is at least one of copper, gold and silver; the particle size of the metal powder is 50-200 nanometers; the thickness of the metal protective layer is 0.01-10 microns.

9. The preparation method of the fluorescent dissolved oxygen sensor membrane as claimed in claim 1, wherein the drying temperature in the steps 1) -4) is room temperature, 30 ℃, 40 ℃, 60 ℃ or 80 ℃, and the relative humidity is 30-70%.

10. The fluorescent dissolved oxygen sensor membrane prepared according to any one of claims 1 to 9, wherein the fluorescent dissolved oxygen sensor membrane is composed of a metal protection layer, a fluorescent layer and a transparent layer in this order from top to bottom.

Technical Field

The invention belongs to the technical field of analytical chemistry and oxygen sensors, and particularly relates to a fluorescent dissolved oxygen sensor diaphragm and a preparation method thereof.

Background

The content of dissolved oxygen in water is an important index for water quality evaluation, the content of the dissolved oxygen is closely related to the oxygen partial pressure in the environment and the temperature of a water body, and the measurement and adjustment of the dissolved oxygen in water are significant in the aspects of environmental protection, biological medicine, industrial production, aquaculture and the like. The conventional measurement methods for dissolved oxygen mainly comprise an iodometric titration method, a clark electrode method and a fluorescence dissolved oxygen measurement method. The fluorescence dissolved oxygen measurement method has the advantages of rapid reaction, accurate and stable performance in the using process, and avoids the defects of regular replacement of electrolyte and semipermeable membrane, complex operation and the like in the measurement process of the traditional electrochemical dissolved oxygen measurement method, so the method brings about the attention of numerous scientific researchers and enterprises at home and abroad. The fluorescence dissolved oxygen measurement method is based on a fluorescence quenching principle, excitation light irradiates a fluorescence indicator to generate emission light (fluorescence or phosphorescence), oxygen has the capacity of dynamically quenching the emission light and takes away energy in a molecular collision mode, and the fluorescence intensity and the fluorescence lifetime of the generated emission light are reduced. With the continuous irradiation of the excitation light, the ability of the fluorescent indicator to generate the emission light is continuously attenuated, and the attenuation cannot be counted. If the fluorescence intensity signal is adopted to calculate the concentration of the dissolved oxygen, the error is large and cannot be compensated by an algorithm, so that the measurement result is inaccurate. In general, the fluorescence dissolved oxygen sensor receives and processes a phase difference signal between emitted light and reference light, the phase difference reflects the fluorescence lifetime of the emitted light, the relation between the fluorescence lifetime and the content of dissolved oxygen in water conforms to a Stern-Volmer formula, and the concentration of the dissolved oxygen in water can be accurately measured according to the method.

The fluorescence dissolved oxygen sensor can measure the dissolved oxygen in water by utilizing the principle of a fluorescence quenching method, and a plurality of related products are available in the market at present. The key part of the sensor is the fluorescent oxygen-dissolving membrane that immobilizes the fluorescent indicator. The preparation of the fluorescent oxygen dissolving film mainly relates to a selection and fixation method of a fluorescent indicator. The fluorescence indicators are various in types, currently, the most commonly used ruthenium pyridine complexes and platinum porphyrin complexes have relatively long fluorescence lifetime, good repeatability and strong oxygen dynamic quenching capacity. In practical application, the fluorescent indicator can be selected according to the required excitation wavelength and emission wavelength. In addition, the fluorescent indicator is usually immobilized on the membrane carrier by a chemical immobilization method, a physical immobilization method (adsorption method, embedding method) or the like. The chemical fixation method is to connect the fluorescent indicator with the membrane carrier through a chemical bond, so that the leakage of the fluorescent indicator can be effectively prevented, but the fluorescence quenching capacity of the fluorescent indicator can be influenced. The physical fixing method is simple to operate and easy to realize, but the leakage problem of the fluorescent indicator is difficult to avoid, and the requirement on the membrane carrier is higher. In addition to good compatibility with fluorescent indicators, film carriers require good film formation, oxygen diffusion, high hydrophobicity, and good adhesion to the carrier substrate. The membrane support may be made from gels, silicone rubber, and other high polymers.

Therefore, there is a need to provide a new membrane for a fluorescence dissolved oxygen sensor to solve the above problems.

Disclosure of Invention

Aiming at the defects in the prior art, the invention provides the fluorescent dissolved oxygen sensor diaphragm and the preparation method thereof, the composition of the film material is adjusted, the metal protective layer is added outside the organic film layer, the external light interference and the leakage of a fluorescent signal can be effectively avoided, in addition, the preparation process of the film material is adjusted, and the fluorescent characteristic, the stability and the processability of the fluorescent film material can be improved by adopting the methods of ultrasonic spraying and screen printing.

In order to achieve the above purposes, the invention adopts the technical scheme that: a preparation method of a fluorescent dissolved oxygen sensor membrane comprises the following steps:

1) mixing polyvinyl chloride powder, diisooctyl phthalate and tetrahydrofuran according to the weight ratio of 5 g: 8 g: 100ml of the mixture is mixed, the mixture is evenly mixed by ultrasound in an ultrasonic machine, a film is formed on the central area of the carrier substrate by silk-screen printing, and a transparent layer is formed by drying;

2) solid particles loaded with a fluorescent indicator, naphthol and an organic volatile solvent are mixed according to the weight ratio of 1g:1 ml: 100ml of the mixture is mixed, uniformly dispersed by ultrasonic waves, sprayed on the surface of the transparent layer by ultrasonic waves, and dried to form a fluorescent layer;

3) uniformly mixing polydimethylsiloxane, ethyl orthosilicate, dibutyltin dilaurate, Triton X-100 and carbon black in a mass ratio of 20:4:1:1:1, then coating the mixture on the surface of a fluorescent layer by screen printing, and drying to form a fluorescent protection layer;

4) metal powder, naphthol ultrasonic and toluene were mixed in a ratio of 1g:1 ml: 200ml of the mixture is uniformly mixed, and the mixture is sprayed on the surface of the fluorescent protective layer by ultrasonic waves and dried to form a metal protective layer.

Further, the method may further comprise treating the carrier substrate prior to preparation: the carrier substrate with the diameter of 3 cm and the thickness of 1 mm is soaked in 1mol/L sodium hydroxide and sulfuric acid for 2-6 hours respectively, and finally washed by absolute ethyl alcohol and dried.

Further, in the step 1), the material of the carrier substrate is quartz glass, sapphire or organic glass with the light transmittance of more than 90%.

Further, the thickness of the transparent layer in the step 1) is 30-120 microns.

Further, the fluorescent indicator in the step 2) is Ru (dpp) capable of being excited by visible light₃ ²⁺、Ru(bpy)₃ ²⁺Or Ru (OEP) ruthenium polypyridine complexes and PtOEP, PtOEPK or Ptfpp platinum porphyrin complexes; the solid particles can be at least one of organic resin powder, organic silicon rubber particles or nano silicon dioxide; the mass fraction of the solid particle loaded fluorescent indicator is 0.1-3%.

Further, the particle size of the solid particles in the step 2) is 10-200 nm; the thickness of the fluorescent layer is 0.5-20 microns.

Further, the thickness of the fluorescent protective layer in the step 3) is 60-150 microns.

Further, the kind of the metal powder in the step 4) is at least one of copper, gold and silver; the particle size of the metal powder is 50-200 nanometers; the thickness of the metal protective layer is 0.01-10 microns.

Further, the drying temperature in the steps 1) to 4) can be room temperature, 30 ℃, 40 ℃, 60 ℃ or 80 ℃, and the relative humidity is 30-70%.

The invention also provides a fluorescent dissolved oxygen sensor diaphragm which sequentially comprises a metal protection layer, a fluorescent layer and a transparent layer from top to bottom.

The invention has the advantages that the composition of the film material is adjusted, the metal protective layer is added outside the organic film layer, the external light interference and the leakage of fluorescent signals can be effectively avoided, in addition, the preparation process of the film material is adjusted, and the fluorescent characteristic, the stability and the processability of the fluorescent film material can be improved by adopting the methods of ultrasonic spraying and silk-screen printing.

Drawings

FIG. 1 is a schematic flow chart of a method for manufacturing a fluorescent dissolved oxygen sensor membrane according to the present invention;

FIG. 2 is a front view of a fluorescent dissolved oxygen sensor diaphragm according to the present invention;

FIG. 3 is a top view of a fluorescent dissolved oxygen sensor membrane according to the present invention.

In the figure: 1-a metal protective layer; 2-a fluorescent protective layer; 3-a fluorescent layer; 4-a transparent layer; 5-carrier substrate.

Detailed Description

In order to make the technical problems solved, the technical solutions adopted, and the technical effects achieved by the present invention clearer, the technical solutions of the embodiments of the present invention will be further described in detail with reference to the accompanying drawings. It is to be understood that the described embodiments are merely exemplary of the invention, and not restrictive of the full scope of the invention. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention.

Referring to fig. 1, fig. 1 is a schematic flow chart of a method for manufacturing a fluorescent dissolved oxygen sensor membrane according to the present invention. The invention provides a preparation method of a fluorescent dissolved oxygen sensor diaphragm, which comprises the following steps:

step 101: polyvinyl chloride powder (PVC for short), diisooctyl phthalate and tetrahydrofuran (THF for short) are mixed according to the proportion of 5 g: 8 g: 100ml of the mixture is mixed, the mixture is evenly mixed by ultrasonic in an ultrasonic machine, a film is formed on the central area of the carrier substrate by silk-screen printing, and a transparent layer is formed by drying.

In one specific example, 0.5g of polyvinyl chloride powder and 0.8g of diisooctyl phthalate were added to 10mL of tetrahydrofuran, mixed by sonication in a sonicator, screen printed to form a film on the central region of the carrier substrate, and dried to form a transparent layer.

It should be noted that the carrier substrate used in the method further needs to be processed as follows before the preparation: the carrier substrate with the diameter of 3 cm and the thickness of 1 mm is soaked in 1mol/L sodium hydroxide and sulfuric acid for 2-6 hours respectively, and finally washed by absolute ethyl alcohol and dried.

Preferably, the material of the carrier substrate is quartz glass, sapphire or organic glass with the light transmittance of more than 90%.

It is emphasized that the transparent layer formed on the carrier substrate in step 101 preferably has a thickness in the range of 30-120 microns to ensure good light transmission through the transparent layer.

Step 102: solid particles loaded with a fluorescent indicator, naphthol and an organic volatile solvent are mixed according to the weight ratio of 1g:1 ml: 100ml of the mixture is mixed, uniformly dispersed by ultrasonic waves, sprayed on the surface of the transparent layer by ultrasonic waves, and dried to form a fluorescent layer.

In a specific embodiment, 0.2g of solid particles loaded with a fluorescent indicator and 0.2mL of naphthol are added into 20mL of organic volatile solvent, uniformly dispersed by ultrasonic waves, sprayed on the surface of the transparent layer by ultrasonic waves, and dried to form a fluorescent layer.

Wherein the fluorescent indicator is Ru (dpp) capable of being excited by visible light₃ ²⁺、Ru(bpy)₃ ²⁺Or Ru (OEP) ruthenium polypyridine complexes and PtOEP, PtOEPK or PtTFPP platinum porphyrin complexes.

The solid particles can be at least one of organic resin powder, organic silicon rubber particles or nano silicon dioxide. Preferably, the mass fraction of the fluorescent indicator loaded on the solid particles is 0.1-3%. The particle size of the solid particles is 10-200 nm.

The phosphor layer prepared in step 102 has a thickness in the range of 0.5-20 microns.

Step 103: uniformly mixing polydimethylsiloxane, ethyl orthosilicate, dibutyltin dilaurate, Triton X-100 and carbon black in a mass ratio of 20:4:1:1:1, then coating the mixture on the surface of a fluorescent layer by screen printing, and drying to form a fluorescent protective layer.

The thickness of the fluorescent protective layer prepared in step 103 is 60-150 μm.

Step 104: metal powder, naphthol ultrasonic and toluene were mixed in a ratio of 1g:1 ml: 200ml of the mixture is uniformly mixed, and the mixture is sprayed on the surface of the fluorescent protective layer by ultrasonic waves and dried to form a metal protective layer.

In a specific embodiment, 0.1g of metal powder and 0.1mL of naphthol are ultrasonically and uniformly dispersed in 20mL of toluene, and the metal powder and the naphthol are ultrasonically sprayed on the surface of the fluorescent protective layer and dried to form the metal protective layer.

Wherein the metal powder is at least one of copper, gold and silver; the particle size of the metal powder is 50-200 nanometers; the thickness of the metal protective layer is 0.01-10 microns.

It should be noted that, when the drying operation is involved in the above steps, the drying temperature may be room temperature, 30 degrees, 40 degrees, 60 degrees or 80 degrees, and the relative humidity is 30-70%.

Referring to fig. 2-3, fig. 2 is a front view of a fluorescent dissolved oxygen sensor membrane according to the present invention, and fig. 3 is a top view of the fluorescent dissolved oxygen sensor membrane according to the present invention. The invention also provides a fluorescent dissolved oxygen sensor diaphragm which sequentially comprises a metal protection layer 1, a fluorescent protection layer 2, a fluorescent layer 3 and a transparent layer 4 from top to bottom.

The metal protection layer 1 is at least one metal powder, and can effectively avoid external light interference and leakage of fluorescence signals. The metal powder is prepared by uniformly dispersing 0.1g of metal powder and 0.1mL of naphthol in 20mL of toluene through ultrasonic waves, spraying the metal powder on the surface of the fluorescent protection layer 2 through ultrasonic waves, and drying the fluorescent protection layer. The thickness of the metal protective layer 1 is 0.01-10 μm.

The fluorescent protective layer 2 is a modified sol-gel film having good oxygen diffusion ability. The fluorescent material is formed by uniformly mixing polydimethylsiloxane, ethyl orthosilicate, dibutyltin dilaurate, Triton X-100 and carbon black in a mass ratio of 20:4:1:1:1, then coating the mixture on the surface of a fluorescent layer 3 through screen printing, and drying the mixture. The thickness of the fluorescent protection layer 2 is 60-150 microns.

The fluorescent layer 3 is an organic resin particle layer loaded with a fluorescent indicator physically embedded in a film material. The fluorescent layer 3 is formed by adding 0.2g of solid particles loaded with the fluorescent indicator and 0.2mL of naphthol into 20mL of organic volatile solvent, uniformly dispersing by ultrasonic waves, spraying the surface of the transparent layer 4 by ultrasonic waves, and drying. The thickness of the fluorescent layer 3 is in the range of 0.5-20 μm.

The transparent layer 4 is a film layer having good adhesiveness and transparency with the sol-gel layer. The transparent layer 4 is formed by adding 0.5g of pvc powder and 0.8g of diisooctyl phthalate in 10mL of THF, ultrasonically mixing the mixture in an ultrasonic machine, screen-printing the mixture on the central area of the carrier substrate 5 to form a film, and drying the film. The transparent layer 4 preferably has a thickness in the range of 30-120 microns.

Compared with the prior art, the fluorescent dissolved oxygen sensor diaphragm and the preparation method thereof provided by the invention have the advantages that the metal protective layer is added outside the organic film layer by adjusting the composition of the film material, so that the external light interference and the leakage of a fluorescent signal can be effectively avoided, in addition, the preparation process of the film material is adjusted, and the fluorescent characteristic, the stability and the processability of the fluorescent film material can be improved by adopting the methods of ultrasonic spraying and screen printing.

It should be understood by those skilled in the art that the fluorescent dissolved oxygen sensor membrane and the method for manufacturing the same according to the present invention are not limited to the examples described in the detailed description, and the above detailed description is only for the purpose of illustrating the present invention and is not intended to limit the present invention. Other embodiments will be apparent to those skilled in the art from the following detailed description, which is intended to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the appended claims.