CN110951392A

CN110951392A - Tetra (4-cumylphenoxy) phthalocyanine lead electrostatic self-assembly film and preparation method thereof

Info

Publication number: CN110951392A
Application number: CN201911279961.XA
Authority: CN
Inventors: 刘大军; 马鹏飞; 王琪
Original assignee: Changchun University of Science and Technology
Current assignee: Changchun University of Science and Technology
Priority date: 2019-12-13
Filing date: 2019-12-13
Publication date: 2020-04-03

Abstract

The invention discloses a method for loading hydrophobic metal phthalocyanine into an electrostatic self-assembly film. Uniformly dispersing hydrophobic metal phthalocyanine in a polyethyleneimine and polyacrylic acid aqueous solution in an ultrasonic oscillation mode, and alternately depositing polyelectrolyte containing the hydrophobic metal phthalocyanine on a substrate by an electrostatic self-assembly method; can prepare a hydrophobic metal phthalocyanine self-assembled film which is stable, transparent and has high metal phthalocyanine content. The preparation method is simple, the conditions are easy to control, the formed film is stable, and the thickness of the film layer can be regulated and controlled according to requirements.

Description

Tetra (4-cumylphenoxy) phthalocyanine lead electrostatic self-assembly film and preparation method thereof

Technical Field

The invention relates to the technical field of third-order nonlinear optical thin film materials, in particular to a hydrophobic phthalocyanine electrostatic thin film material and a preparation method thereof.

Background

Electrostatic self-assembly is a simple and convenient nano-film preparation technology, and has been widely applied to the preparation of various functional film materials. The basic principle of electrostatic self-assembly can be explained as that two polyelectrolytes or nano ions with opposite charges are mutually attracted through electrostatic adsorption and deposited on the surface of a substrate to form a self-assembled film. The substrate is repeatedly and alternately soaked in two different electrolyte solutions to obtain the electrostatic self-assembly film which grows layer by layer. The method for preparing the film has simple operation and high film forming efficiency, the internal structure of the film has certain regularity, the thickness is controllable, and the film can be assembled on the surfaces of various substrates, thereby being a technical scheme with high efficiency and low cost.

The polymeric surfactant has dispersing, emulsifying, protective colloid, solubilizing, and the like effects, and is generally used as an emulsifier, solubilizer, dispersant, and the like. The high molecular surfactant, like the common surfactants, can be classified into anionic surfactants, cationic surfactants, and nonionic surfactants. Polyethyleneimine (PEI) is a common cationic surfactant, positive charges are often provided in the electrostatic self-assembly process, and the PEI has a dendritic structure and has strong covering and encapsulating capacity on dispersed particles; polyacrylic acid (PAA) is a common anionic surfactant capable of providing negative charges and has a long chain packing structure, and particles can be effectively dispersed by intermolecular entanglement. In addition, the thin film material formed by electrostatic self-assembly of PEI and PAA has good light transmission, and the transmittance of the thin film material can reach 90%.

Metal phthalocyanines are the most common and widely studied nonlinear optical materials. The metal phthalocyanine has a two-dimensional plane macrocyclic conjugated system, an 18-electron conjugated structure enables the metal phthalocyanine to have a larger nonlinear optical effect and a faster nonlinear response speed, and the third-order nonlinear polarizability of the existing metal phthalocyanine can reach 10^-11esu order of magnitude, response times are of the picosecond order (Nalwa H S, hand M.third-order nonlinear optical properties of porphrazine, phthalocyanines and naphthalocyanine derivatives: purifying the effect of pi-conjugation length on third-order nonlinear optical properties of two-dimensional molecules [ J-S].1999,245(1):17-26.). Furthermore, all-purposeDifferent substituents are introduced to obtain metal phthalocyanine materials with different physicochemical properties.

Electrostatic self-assembly can produce various functional thin films in order, however, hydrophobic metal phthalocyanines are difficult to form stable polymer multilayer films by electrostatic self-assembly without hydrophilic functional groups. The work provides a new method for effectively loading the hydrophobic metal phthalocyanine into the polymer film in an electrostatic self-assembly mode, and the method has wide application prospect in the preparation of optical devices.

Disclosure of Invention

The invention aims to solve the technical problem that hydrophobic metal phthalocyanine is loaded in a polymer film in an electrostatic self-assembly mode, and the polymer film has good permeability and three-order nonlinear optical properties.

In order to solve the technical problems, the invention provides a method for preparing a multilayer film by electrostatic self-assembly of a metal phthalocyanine loaded high molecular surfactant.

The polymer film adopts polyethyleneimine/tetra (4-cumylphenoxy) lead phthalocyanine (PEI/PdPC) and polyacrylic acid/tetra (4-cumylphenoxy) lead phthalocyanine (PAA/PdPC) micelles to carry out electrostatic self-assembly,

the molecular weight of the polyelectrolyte is as follows: polyethyleneimine 750000 and polyacrylic acid 100000.

The technical scheme of the preparation method of the polyelectrolyte/tetra (4-cumylphenoxy) phthalocyanine lead electrostatic self-assembly film is as follows:

soaking the substrate in Piranha washing liquor (prepared by mixing 30% hydrogen peroxide and concentrated sulfuric acid in a volume ratio of 3: 7), heating and boiling until no bubbles are generated, washing the substrate with deionized water, and drying the substrate with nitrogen for later use.

Preparing polyethyleneimine into a deionized water solution with the concentration of 1mg/mL, adjusting the pH value to 9.5, preparing tetra (4-cumylphenoxy) phthalocyanine lead into a dichloromethane solution with the concentration of 1mg/mL, mixing the solution and the dichloromethane solution according to the volume ratio of 5:1, performing ultrasonic dispersion to form a uniform dispersion solution, and volatilizing the dichloromethane solution at room temperature to form a cationic electrolyte solution.

Preparing polyacrylic acid into a deionized water solution with the concentration of 1mg/mL, adjusting the pH value to be 4.0, preparing tetra (4-cumylphenoxy) phthalocyanine lead into a dichloromethane solution with the concentration of 1mg/mL, mixing the two solutions according to the volume ratio of 5:1, performing ultrasonic dispersion to form a uniform dispersion solution, volatilizing the dichloromethane solution at room temperature to form an anionic electrolyte solution.

Immersing the substrate into a cationic electrolyte solution for 15 minutes, adsorbing PEI/PdPC on the surface of the substrate through static electricity, washing and airing the substrate through deionized water, immersing the substrate into an anionic electrolyte solution for 15 minutes, adsorbing PAA/PdPC on the surface of a film layer through static electricity, and washing and airing the substrate through the deionized water to form a periodic electrostatic self-assembly film. The above process is repeated to prepare a multilayer electrostatic self-assembled film.

And after the films are dried in the air, two films are taken to be attached and compacted by deionized water, and after the films are dried in the air, the surface film layer is removed for optical test.

Preferably, the concentration of the polymer micelle is 1mg/mL, and the doping amount of the phthalocyanine is 0.2 mg/mL.

Preferably, the preparation cycle number of the self-assembled film layer is more than 8 cycles.

According to the invention, by means of coating hydrophobic metal phthalocyanine with polyelectrolyte and by using the principle of electrostatic self-assembly, cationic polyelectrolyte PEI/PdPC and anionic polyelectrolyte PAA/PdPC are self-assembled on a substrate to form a film; the prepared metal phthalocyanine loaded film has good permeability, and does not influence the third-order nonlinear optical performance of the metal phthalocyanine. The preparation method has the advantages of simple preparation process, low requirement on equipment, easily controlled conditions, adjustable thickness of the prepared film and good stability.

Drawings

FIG. 1 is structural formulas of a cationic Polyelectrolyte (PEI) and an anionic Polyelectrolyte (PAA), and it can be seen that PEI has a dendritic structure and PAA has a long chain assembly structure.

FIG. 2 is a graph showing the nano-particle size analysis of the polyelectrolyte after loading with tetrakis (4-cumylphenoxy) lead phthalocyanine in example 1, in which it can be seen that the micelle diameter is between 0.1 and 1 μm;

FIG. 3 is a schematic diagram of the preparation of the self-assembled film of example 1;

FIG. 4 is an ultraviolet absorption spectrum of the self-assembled films of examples 2-6, wherein different absorbances in the graph indicate that the self-assembled films with different layers have different contents of lead tetra (4-cumylphenoxy) phthalocyanine, and the thicker the film layer is, the more the film layer is, the load capacity is increased;

FIG. 5 is a scanning electron micrograph of the self-assembled thin film of example 6, from which it can be seen that the film thickness is 19.14 μm, while supported tetra (4-cumylphenoxy) lead phthalocyanine particles are clearly observed;

FIG. 6 is a Z-scan of the opening of the self-assembled film of example 2, no curve was fit due to the low concentration of the supported lead tetra (4-cumylphenoxy) phthalocyanine;

FIG. 7 is a Z-scan of the holes formed in the self-assembled film laminates of examples 3-6, and it can be seen from the fitting curve that the content of tetra (4-cumylphenoxy) phthalocyanine lead in the film is increased and the third-order nonlinear effect is enhanced with the increase of the film thickness.

Detailed Description

The present invention will be described below by way of specific embodiments, but is not limited thereto and can be applied to various hydrophobic materials.

Example 1

(1) Cleaning a glass substrate by using reagents such as ethanol, acetone and the like, immersing the substrate into a prepared Piranha washing solution, mixing 30% of hydrogen peroxide and concentrated sulfuric acid in the Piranha washing solution at a ratio of 3:7, heating and boiling the Piranha washing solution until the Piranha washing solution is over all the substrates, hydroxylating the surface (namely carrying negative charges) until no bubbles overflow from the glass surface, and storing the substrate in mother liquor after the substrate is treated for later use.

(2) Preparing two polyelectrolyte solutions, weighing polyelectrolytes with corresponding mass, adding deionized water to prepare an aqueous solution with the concentration of 1mg/mL, adjusting the pH value of the solution after the polyelectrolytes are dissolved in water, adjusting the pH value of PEI to 9.5 by using a sodium hydroxide solution, and adjusting the pH value of PAA to 4.0 by using a hydrochloric acid solution.

(3) Dissolving tetra (4-cumylphenoxy) lead phthalocyanine with corresponding mass in 2mL of dichloromethane solution, wherein the concentration of the mass of the phthalocyanine relative to the polyelectrolyte solution is 0.2mg/mL, slowly dropping the solution into the polyelectrolyte solution by using a syringe under the ultrasonic condition, ultrasonically dispersing the solution under stirring until no tetra (4-cumylphenoxy) lead phthalocyanine drops drop exists, stirring the solution overnight after dispersion, volatilizing the organic solvent to form polyelectrolyte colloids (PEI/PdPC, PAA/PdPC) coating the phthalocyanine, wherein the solution is uniform and stable green liquid.

(4) Taking out the substrate in the step (1), washing with deionized water, and drying with nitrogen; soaking in PEI/PdPC solution for 15min, taking out, soaking and cleaning with deionized water for 3min, soaking in PAA/PdPC solution for 15min, taking out, soaking and cleaning with deionized water for 3min, and the film obtained by the above processes is named as a double layer and is a period. Repeating the above steps 8 times to obtain 8 cycles of electrostatic self-assembled film with thickness of about 2 μm.

Example 2

Repeating the example 1 to obtain two pieces of electrostatic self-assembled films with the same thickness and the same load of the tetra (4-cumylphenoxy) phthalocyanine lead; and (3) attaching the two films by using deionized water, compacting, pressing for 3 days, and scraping the films on the two side surfaces of the substrate to obtain the electrostatic self-assembly 8-period adhesive film with good transparency.

Example 3

Example 1 and example 2 were repeated, and the electrostatic self-assembly step was repeated 16 times to obtain an electrostatic self-assembly bonding film having a cycle number of 16.

Example 4

Example 1 and example 2 were repeated, and the electrostatic self-assembly step was repeated 24 times to obtain an electrostatic self-assembled adhesive film having a cycle number of 24.

Example 5

Example 1 and example 2 were repeated, and the electrostatic self-assembly step was repeated 28 times to obtain an electrostatic self-assembly lamination film with a cycle number of 28.

Example 6

Example 1 and example 2 were repeated, and the electrostatic self-assembly step was repeated 32 times to obtain an electrostatic self-assembly bonding film having a cycle number of 32.

Example 7

The structure and the morphology of the prepared tetra (4-cumylphenoxy) phthalocyanine lead loaded polymer film are characterized by methods such as ultraviolet spectroscopy (UV-vis), Scanning Electron Microscopy (SEM), Z scanning and the like.

The foregoing is a detailed description of the invention in conjunction with specific embodiments thereof, and it is not intended that the invention be limited to these specific embodiments. It should be understood by those skilled in the art that various changes and substitutions may be made in accordance with the technical solution and the inventive concept of the present invention, and the same properties or uses should be considered as the protection scope of the present invention.

Claims

1. The electrostatic self-assembly film of tetra (4-cumylphenoxy) phthalocyanine lead is characterized in that: adopting polyethyleneimine-solubilized tetra (4-cumylphenoxy) lead phthalocyanine (PEI/PdPC) as a cationic electrolyte solution and polyacrylic acid-solubilized tetra (4-cumylphenoxy) lead phthalocyanine (PAA/PdPC) as an anionic electrolyte solution, and forming a film on the surface of the substrate through electrostatic self-assembly.

2. The method for preparing an electrostatically self-assembled film as claimed in claim 1, which comprises the steps of:

(1) soaking the substrate in Piranha washing liquor (prepared by mixing 30% hydrogen peroxide and concentrated sulfuric acid in a volume ratio of 3: 7), heating and boiling until no bubbles are generated, washing the substrate with deionized water, and drying the substrate with nitrogen for later use.

(2) Preparing polyethyleneimine into a deionized water solution with the concentration of 1mg/mL, adjusting the pH value to 9.5, preparing tetra (4-cumylphenoxy) phthalocyanine lead into a dichloromethane solution with the concentration of 1mg/mL, mixing the solution and the dichloromethane solution according to the volume ratio of 5:1, performing ultrasonic dispersion to form a uniform dispersion solution, and volatilizing the dichloromethane solution at room temperature to form a cationic electrolyte solution.

(3) Preparing polyacrylic acid into a deionized water solution with the concentration of 1mg/mL, adjusting the pH value to be 4.0, preparing tetra (4-cumylphenoxy) phthalocyanine lead into a dichloromethane solution with the concentration of 1mg/mL, mixing the two solutions according to the volume ratio of 5:1, performing ultrasonic dispersion to form a uniform dispersion solution, volatilizing the dichloromethane solution at room temperature to form an anionic electrolyte solution.

(4) Immersing the substrate into a cationic electrolyte solution for 15 minutes, adsorbing PEI/PdPC on the surface of the substrate through static electricity, washing and airing the substrate through deionized water, immersing the substrate into an anionic electrolyte solution for 15 minutes, adsorbing PAA/PdPC on the surface of a film layer through static electricity, and washing and airing the substrate through the deionized water to form a periodic electrostatic self-assembly film. The above process is repeated to prepare a multilayer electrostatic self-assembled film.

3. The film of claim 1, wherein the substrate is selected from the group consisting of quartz, glass, and silicon wafer.