CN105153699A - Preparation method of hyper branched copolymerized polyimide/zinc oxide (ZnO) hybrid insulated film - Google Patents

Abstract

The invention provides a method for preparing a hyperbranched copolymerized polyimide/zinc oxide (ZnO) hybrid insulating film, comprising the following steps: the preparation of a hyperbranched copolymerized polyamic acid film: using 3, 3', 4, 4' -diphenyl ether tetracarboxylic dianhydride, triamine monomer 1,3,5-tris[4-(4-aminophenoxy)phenyl]benzene and 4,4'-diaminodiphenyl ether The polyamide is used as a raw material, and the polycondensation reaction is carried out at a molar ratio of 1:0.4:0.5 to obtain a yellow viscous transparent solution; then, the obtained solution is dropped on a glass plate with a silica gel frame, and after drying, a hyperbranched copolymerized polyamide is obtained. Acid film; complete the imidization of the hyperbranched copolyamic acid film and the formation of zinc oxide nanoparticles in one step: configure the zinc chloride solution, and then completely soak the hyperbranched copolyamic acid film in the zinc chloride solution. The hyperbranched copolymerized polyamic acid film is taken out and rinsed; the product is obtained after baking. The invention lowers its dielectric constant by hybridizing hyperbranched polyimide and nano-zinc oxide, increases the insulation of product materials, improves its heat resistance and mechanical properties, and satisfies the material requirements of different electronic components.

Description

A kind of preparation method of hyperbranched copolymerized polyimide/zinc oxide hybrid insulation film

technical field

The invention relates to the technical field of polymer material preparation, in particular to a method for preparing a hyperbranched copolymerized polyimide/zinc oxide hybrid insulating film.

Background technique

The rapid development of modern science and technology has put forward higher requirements for the types and properties of materials, and the hybridization of materials can meet the requirements of some special properties. Hybrid materials are characterized by combining the advantages of various components and playing a multifunctional role. Appropriate hybridization of polyimide can not only retain its excellent performance, but also have some new characteristics to meet the higher requirements of modern industrial development for polyimide performance. Polyimide can effectively block electron migration, prevent chemical corrosion, enhance the moisture resistance and mechanical properties of electronic devices, so polyimide can be used as a key insulating material in electrical and electronics and has a wide range of applications. Occupies a unique position in electrical insulation. In order to achieve higher integration, the modern microelectronics industry requires smaller and smaller chip sizes, and the delay time of signal transmission in the chip will increase accordingly. This delay time is proportional to the dielectric constant of the interlayer insulating material. In order to increase the transmission speed of the signal, the dielectric constant of the interlayer insulating material must be reduced to 2.0-2.6. Usually, the dielectric constant of the polyimide material is 3.0-3.5, which is difficult to meet this requirement.

In order to reduce the dielectric constant of polyimide, among the existing researches, more composite materials are obtained by blending with linear polyimide, and this method is often due to the small size of the blend Effect is easy to agglomerate, so that the composite material can not effectively improve its dielectric properties.

Contents of the invention

The purpose of the present invention is to provide a method for preparing a hyperbranched copolymerized polyimide/zinc oxide hybrid insulating film, by hybridizing hyperbranched polyimide and nano-zinc oxide to reduce its dielectric constant and increase the insulation of the product , At the same time, it can improve its heat resistance and mechanical properties, and meet the material requirements of different electronic components.

In order to achieve the above object, the technical scheme adopted in the present invention is as follows:

A preparation method of hyperbranched copolymerized polyimide/zinc oxide hybrid insulating film, comprising the steps of:

1) Preparation of hyperbranched copolymerized polyamic acid membrane (co-HBPAA): using 3,3',4,4'-diphenyl ether tetracarboxylic dianhydride (ODPA), triamine monomer 1,3,5-tri [4-(4-Aminophenoxy)phenyl]benzene (TAPOPB) and 4,4'-diaminodiphenyl ether (ODA) three monomers are used as raw materials in a molar ratio of 1:0.4:0.5 Polycondensation reaction: first dissolve 3,3',4,4'-diphenyl ether tetracarboxylic dianhydride with N-methyl-2-pyrrolidone (NMP), and slowly add it dropwise to the tank containing 1,3, 5-tris[4-(4-aminophenoxy)phenyl]benzene and 4,4'-diaminodiphenyl ether in N-methyl-2-pyrrolidone solution for polycondensation reaction to obtain yellow viscous Transparent solution; Then, the solution obtained is dripped on a glass plate with a silica gel frame, then put into a vacuum oven for drying (to remove residual solvent), to obtain a hyperbranched copolymerized polyamic acid film, which is peeled off from the glass plate for subsequent use;

2) Complete the imidization of the hyperbranched copolyamic acid membrane and the formation of zinc oxide (ZnO) nanoparticles in one step: prepare a zinc chloride (ZnCl ₂ ) solution, and then completely soak the hyperbranched copolyamic acid membrane in the chloride In the zinc solution, take out the hyperbranched copolymerized polyamic acid film after soaking, rinse with deionized water (to remove the ZnCl solution remaining _on the film); fix the film with clips (to prevent the film from curling during thermal imidization) ) and bake in an oven to complete the imidization of the hyperbranched copolymerized polyamic acid film and the formation of zinc oxide nanoparticles in one step to obtain the product.

According to the above scheme, the dropping of the 3,3', 4,4'-diphenyl ether tetracarboxylic dianhydride is carried out under the conditions of nitrogen protection and ice-water bath, the dropping time is 1h, and the polycondensation reaction is The reaction was continued for 12h in an ice-water bath.

According to the above scheme, the drying temperature of the vacuum oven drying is 60° C., and the drying time is 12 hours.

According to the above scheme, the concentration of the zinc chloride solution is 2mol/L. When configuring, add an appropriate amount of concentrated hydrochloric acid until the solution is just clear and transparent, to prevent the _ZnCl2 particles from being dissolved in water and hydrolyzing to produce zinc hydroxide Zn(OH ) ₂ flocculent precipitation, resulting in a decrease in Zn ²⁺ concentration.

According to the above scheme, the soaking time is 4h.

According to the above scheme, the number of times of rinsing with deionized water is 3 times.

According to the above scheme, the specific process of baking is as follows: baking at 150° C., 200° C., 250° C. and 300° C. for 1 hour respectively.

The beneficial effects of the present invention are:

1) In the present invention, ion exchange occurs between hyperbranched polyamic acid, a precursor of hyperbranched polyimide, and zinc chloride solution, and each carboxylic acid provides access points for zinc ions, and nano-zinc oxide is obtained after one-step heat treatment. Physical adsorption on the carbonyl group on the imide ring effectively reduces the agglomeration of nanoparticles. At the same time, there are many cavity structures in the matrix hyperbranched polyimide structure, which increases the air component in the material, so the two comprehensively improve the The dielectric properties and insulation of the hybrid film reduce the dielectric constant of the material;

2) The introduction of nanoparticles in the present invention improves the thermal and mechanical properties of the material, improves the dimensional stability of the material, and is more suitable for application in the field of microelectronics.

Description of drawings

Fig. 1 is the co-HBPI/ZnO hybrid film synthetic route schematic diagram of the present invention;

Fig. 2 is a schematic diagram of the process of preparing co-HBPI/ZnO hybrid film in one step of the present invention;

Fig. 3 is the energy dispersive x-ray (EDX) energy spectrogram of product of the present invention;

Fig. 4 is the thermogravimetric analysis (TGA) curve figure of pure co-HBPI film and product of the present invention under air atmosphere;

Fig. 5 is the stress-strain curve figure of pure co-HBPI film and product of the present invention;

Fig. 6 is the scanning electron microscope (SEM) figure of the surface contact angle performance of pure co-HBPI film and product of the present invention;

Fig. 7 is a graph showing the variation of dielectric constant with frequency of pure co-HBPI film and the product of the present invention.

Detailed ways

The technical solutions of the present invention will be described below in conjunction with the accompanying drawings and embodiments.

The invention provides a method for preparing a hyperbranched copolymerized polyimide/zinc oxide hybrid insulating film, comprising the following steps:

1) Preparation of hyperbranched copolymerized polyamic acid film (co-HBPAA): three monomers, ODPA, TAPOPB and ODA, were used as raw materials, and the polycondensation reaction was carried out at a molar ratio of 1:0.4:0.5 (as shown in Figure 1): Dissolve ODPA with 10ml NMP. After it is completely dissolved, slowly add it dropwise into the two-necked flask containing 10ml TAPOPB and ODA NMP solution within 1h in an ice-water bath under _N2 atmosphere. After the addition is complete, continue the ice-water bath. reaction in the middle for 12 hours to obtain a yellow viscous transparent solution; then, drop the obtained solution on a glass plate with a silica gel frame, put it in a vacuum oven at 60°C for 12 hours to remove the residual solvent, and obtain a hyperbranched copolymerized polyamic acid film , peel off from the glass plate for later use;

2) Complete the imidization of co-HBPAA and the formation of ZnO nanoparticles in one step: first configure a 2mol/L zinc chloride solution, and add a few drops of concentrated hydrochloric acid until the solution is just clear and transparent; the prepared hyperbranched copolymerized polyamic acid The membrane was completely soaked in the prepared zinc chloride solution for 4 hours, then the membrane was taken out, and rinsed repeatedly with deionized water for 3 times to remove the remaining ZnCl ₂ solution on the membrane; then, the membrane was fixed with clips and placed in an oven. Bake at 150°C, 200°C, 250°C and 300°C for 1 hour respectively to complete the imidization of co-HBPAA and the formation of ZnO nanoparticles in one step, and obtain the product hyperbranched copolymerized polyimide/zinc oxide hybrid Insulating thin film (co-HBPI/ZnO hybrid thin film) (the schematic diagram of the process is shown in Figure 2).

In order to quantitatively analyze the distribution of ZnO in the co-HBPI film, the EDX spectrum of the product of the present invention was determined experimentally (see Figure 3). The results show that the measured Zn content is 1.46%, indicating that ZnO has indeed been introduced.

Thermal performance test: The thermal performance of the product of the present invention is characterized by TGA (see Figure 4). Table 1 lists the thermal weight loss temperature of pure co-HBPI film and 5% and 10% products of the present invention. It can be seen from Figure 4 that with the introduction of ZnO particles, the thermal stability of the hybrid film is slightly improved, but the magnitude of the increase is not very large. Generally speaking, the interfacial force between particles and matrix greatly affects the thermal stability of hybrid materials. ZnO particles are mainly adsorbed on the surface of the polyimide film by intermolecular force, so the spatial structure of co-HBPI molecules changes little, and only the attraction of ZnO to the molecular chain is increased on the surface, resulting in a heterogeneous macroscopic appearance. A slight improvement in the thermal performance of the thin film. Can also find out from Fig. 4, under air atmosphere, when heating up to 800 ℃, the residual amount of pure co-HBPI film is zero, and the residual amount of the product of the present invention is about 1.81%, is the content of ZnO, and EDX energy The Zn content measured by the spectrum is roughly consistent.

Table 1 pure co-HBPI film and product of the present invention 5%, 10% weight loss temperature

Mechanical properties testing: Unlike usual linear polyimides, hyperbranched polyimides are considered to have relatively poor mechanical properties due to the lack of physical entanglement in their spherical molecular structures. In the present invention, ZnO particles are successfully introduced into the copolymerized polyimide film, which increases the tensile strength and elongation at break of the material. It can be seen from Table 2 that with the loading of ZnO, the tensile strength increased from 96.14MPa to 103.41MPa, and the elongation at break increased from 10.51% to 14.60% (as shown in the curve trend of Figure 5). ZnO particles improved the mechanical properties of the co-HBPI film mainly due to the interaction force between ZnO particles and the matrix, which is helpful for stress transmission. For the whole system, ZnO particles can absorb energy well and transmit stress, weakening the material damage caused by stress concentration, thereby improving the mechanical properties of the material.

The mechanical performance test result of table 2 pure co-HBPI membrane product of the present invention

Surface contact angle test: It is used to measure the surface contact angle (CA) of the film and quantitatively determine its effect on water. The test results show (see Figure 6) that after loading ZnO particles, the CA value of the product of the present invention is reduced from 101.5° to 79.7° of the pure co-HBPI film, that is, from the original hydrophobicity (CA>90°) to Hydrophilic (CA<90°). Although the SEM image (Figure 7) shows that after adding ZnO, the co-HBPI film changes from smooth to rough, which theoretically enhances the hydrophobicity of the film, but the nano-zinc oxide without surface treatment is polar and it is hydrophilic Sexual nano powder. In addition, compared with ordinary zinc oxide, nano-zinc oxide is a porous micro-powder material. There are a large number of strongly polar hydroxyl groups on its surface, which has a stronger ability to absorb water and exhibits certain hydrophilic properties. The hydroxyl groups on the nano-ZnO contribute more to the hydrophilicity than the roughness brought by them, so the whole hybrid film exhibits hydrophilicity.

Dielectric performance test: Fig. 7 is a graph showing the variation of the dielectric constant with frequency of the pure co-HBPI film and the product of the present invention, and the frequency range is 50 kHz to 1000 kHz. As shown in Figure 7, the dielectric constants of the pure co-HBPI film and the product of the present invention decrease in different degrees with the increase of the test frequency, and are 3.01 and 2.61 respectively at a test frequency of 1 MHz. Among them, the dielectric constant of pure co-HBPI film is relatively low in polyimide, the main reason is that the hyperbranched structure lacks chain entanglement, and many cavity structures are formed in the matrix, which introduces more low dielectric constant. The air makes the dielectric constant of the pure co-HBPI film lower than that of ordinary linear polyimide; and the introduction of nano-ZnO forms a physical adsorption and hybrid structure with the matrix, which inhibits the polarization of the material and reduces the material Therefore, the synergistic effect of the two aspects makes the dielectric constant of the product of the present invention have a relatively large decline compared with the pure co-HBPI film, and basically meets the insulation requirements of the microelectronics industry.

The above embodiments are only used to illustrate and not limit the technical solutions of the present invention. Although the above embodiments have described the present invention in detail, those skilled in the art should understand that the present invention can be modified or replaced without departing from the present invention. Any modifications and partial substitutions in the spirit and scope shall fall within the scope of the claims of the present invention.

Claims (7)

1. a preparation method for hyperbranched copolyimide/zinc oxide hybridization insulation film, is characterized in that, comprise the steps:

1) preparation of hyperbranched copolyamide sorrel: adopt 3, 3 ', 4, 4 '-diphenyl ether tetraformic dianhydride, Triamine monomer 1, 3, 5-tri-[4-(4-amido phenoxy group) phenyl] benzene and 4, 4 '-diaminodiphenyl oxide, three kinds of monomers are raw material, molar ratio with 1: 0.4: 0.5 carries out polycondensation: first dissolve 3 with METHYLPYRROLIDONE, 3 ', 4, 4 '-diphenyl ether tetraformic dianhydride, until completely dissolved, slowly be added drop-wise to and be equipped with 1, 3, 5-tri-[4-(4-amido phenoxy group) phenyl] benzene and 4, polycondensation is carried out in the METHYLPYRROLIDONE solution of 4 '-diaminodiphenyl oxide, obtain the clear solution of clear yellow viscous, then, the solution obtained is dropped on the sheet glass with silica gel frame, then it is dry to put into vacuum drying oven, obtains hyperbranched copolyamide sorrel, peels off for subsequent use from sheet glass,

2) step completes the hyperbranched imidization of copolyamide sorrel and the formation of zinc oxide nano-particle: configuration liquor zinci chloridi, then hyperbranched copolyamide sorrel is fully immersed in liquor zinci chloridi, the hyperbranched copolyamide sorrel of taking-up after immersion completes, with deionized water rinsing; Toast with putting into baking oven after clip fixed film, a step completes the hyperbranched imidization of copolyamide sorrel and the formation of zinc oxide nano-particle, obtained product.

2. the preparation method of hyperbranched copolyimide/zinc oxide hybridization insulation film according to claim 1; it is characterized in that; described 3; 3 '; 4; the dropping of 4 '-diphenyl ether tetraformic dianhydride carries out under the condition of nitrogen protection and ice-water bath, and time for adding is 1h, and described polycondensation is successive reaction 12h in ice-water bath.

3. the preparation method of hyperbranched copolyimide/zinc oxide hybridization insulation film according to claim 1, is characterized in that, the drying temperature of described vacuum drying oven drying is 60 DEG C, and time of drying is 12h.

4. the preparation method of hyperbranched copolyimide/zinc oxide hybridization insulation film according to claim 1, is characterized in that, the concentration of described liquor zinci chloridi is 2mol/L, when configuring, also adds appropriate concentrated hydrochloric acid until solution just clear.

5. the preparation method of hyperbranched copolyimide/zinc oxide hybridization insulation film according to claim 1, is characterized in that, described soak time is 4h.

6. the preparation method of hyperbranched copolyimide/zinc oxide hybridization insulation film according to claim 1, is characterized in that, described deionized water rinsing number of times is 3 times.

7. the preparation method of hyperbranched copolyimide/zinc oxide hybridization insulation film according to claim 1, is characterized in that, the detailed process of described baking is: at the temperature of 150 DEG C, 200 DEG C, 250 DEG C and 300 DEG C, toast 1h respectively.