阅读说明：本技术 一种轻质耐高温聚酰亚胺玻璃微珠芯材的制备方法 (Preparation method of light high-temperature-resistant polyimide glass bead core material ) 是由 杨涛 张朋 包建文 钟翔屿 李晔 于 2019-09-23 设计创作，主要内容包括：本发明涉及一种轻质耐高温聚酰亚胺玻璃微珠芯材的制备方法,包括以下步骤：将二胺单体溶于有机溶剂获得浓度为10％-60％wt的二胺溶液,然后将封端剂和二酐单体溶于有机溶剂并混合均匀后倒入上述二胺溶液,然后在0℃-120℃下进行聚合反应,获得浓度为5％-60％wt聚酰亚胺溶液,再与闭孔玻璃微珠复合制备而成。本发明轻质耐高温聚酰亚胺玻璃微珠芯材在航空航天这类需要使用耐高温聚酰亚胺复合材料替代金属结构的领域具有较好的应用前景；进行结构设计后的轻质耐高温聚酰亚胺玻璃微珠芯材更可以使用于聚酰亚胺树脂适用的多个领域实现减重,降低生产使用成本的作用。(The invention relates to a preparation method of a light high-temperature-resistant polyimide glass bead core material, which comprises the following steps: dissolving diamine monomer in organic solvent to obtain diamine solution with concentration of 10-60 wt%, dissolving end capping agent and dianhydride monomer in organic solvent, mixing homogeneously, pouring the mixture into the diamine solution, polymerizing at 0-120 deg.c to obtain polyimide solution with concentration of 5-60 wt%, and compounding with closed-cell glass bead. The light high-temperature-resistant polyimide glass bead core material has a good application prospect in the fields of aerospace and the like which need to use a high-temperature-resistant polyimide composite material to replace a metal structure; the light high-temperature-resistant polyimide glass bead core material subjected to structural design can be used for realizing weight reduction in multiple fields suitable for polyimide resin, and the production and use cost is reduced.)

1. The preparation method of the light high-temperature-resistant polyimide glass bead core material is characterized by comprising the following steps of:

(1) dissolving a diamine monomer in an organic solvent to obtain a diamine solution with the concentration of 10-60 wt%, then dissolving a blocking agent and a dianhydride monomer in the organic solvent, uniformly mixing, pouring the mixture into the diamine solution, and then carrying out polymerization reaction at 0-120 ℃ to obtain a polyimide solution with the concentration of 5-60 wt%;

(2) simultaneously adding the closed-cell glass beads and the polyimide solution obtained in the step (1) into a mechanical blending device and fully mixing to obtain a glass bead polyimide solution mixture;

(3) and (3) pouring the mixture of the glass bead and the polyimide solution obtained in the step (2) into a forming die, and curing for 1-10 hours at the temperature of 320-400 ℃ and the pressure of 0.1-5.0 MPa to obtain the light high-temperature-resistant polyimide glass bead core material.

2. The method for preparing the light high-temperature-resistant polyimide glass microsphere core material as claimed in claim 1, wherein the molar ratio of the diamine monomer, the dianhydride monomer and the end capping agent in the first step is (n + 1): n: 2, wherein n is any integer from 1 to 8.

3. The method for preparing the light high temperature resistant polyimide glass microsphere core material as claimed in claim 1, wherein the organic solvent is one or more of methanol, ethanol, butanol, tetrahydrofuran, dioxane, N-dimethylacetamide, N-methylpyrrolidone, m-cresol and N, N-dimethylformamide.

4. The method for preparing the light high temperature resistant polyimide glass microsphere core material as claimed in claim 1, wherein the diamine monomer is one of BPDA and 6FDA monomers.

5. The method for preparing the light high temperature resistant polyimide glass microsphere core material as claimed in claim 1, wherein the dianhydride monomer is one of APB, 3,4-ODA and m-PDA.

6. The method for preparing the light high temperature resistant polyimide glass microsphere core material as recited in claim 1, wherein the end-capping reagent is one of norbornene anhydride or phenylethynyl phthalic anhydride.

7. The method for preparing the light high-temperature-resistant polyimide glass bead core material as claimed in claim 6, wherein the structural formula of the norbornene anhydride is as follows:

the structural formula of the phenylethynyl phthalic anhydride is as follows:

8. the preparation method of the light high-temperature-resistant polyimide glass bead core material as claimed in claim 1, wherein the mass ratio of the closed-cell glass beads to the polyimide solution is as follows: 1-70: 100.

9. The method for preparing the light high temperature resistant polyimide glass bead core material as claimed in claim 8, wherein the particle size of the closed-cell glass beads is 10-250 μm.

10. The method for preparing the light high temperature resistant polyimide glass bead core material as claimed in claim 1, wherein the mechanical blending device comprises a mixing unit and a heating unit.

Technical Field

The invention relates to the technical field of high polymer materials, in particular to a preparation method of a light high-temperature-resistant polyimide glass bead core material.

Background

Polyimide is a high-temperature-resistant high polymer material with excellent comprehensive performance, and the polyimide composite material has excellent heat resistance, mechanical property, dielectric property, good solvent resistance and the like, and is widely applied to various fields of aerospace, war industry, national defense and the like. Because the traditional low-density composite sandwich structure does not have the high-temperature resistance, the further application of the high-temperature-resistant polyimide composite material in the structure is limited aiming at the requirement that the complex parts needing the sandwich structure are difficult to realize high-temperature resistance and weight reduction. Therefore, on the premise of ensuring that the original thermodynamic performance of the polyimide interlayer filling material is kept, the discovery, preparation and application of the light high-temperature-resistant polyimide glass bead core material have important significance, and the light high-temperature-resistant polyimide glass bead core material can be widely applied to the filling field of high-temperature-resistant interlayer structures and special-shaped structures in various industries such as aerospace, military industry, national defense and the like.

In order to reduce the weight of an aircraft structure, a resin-based composite material with excellent performance is generally used, and further reduction of the weight by adopting a low-density sandwich structure also becomes an effective means aiming at the further requirement of a high-speed aircraft on reduction of the weight. For example, the method for forming a sandwich structure disclosed in the prior art can realize the formation of a large-size honeycomb sandwich structure with strong weight reduction capability, but the materials used in the method are mostly epoxy, bismaleimide, phenolic aldehyde and other resin matrixes and plastic particles used at medium and low temperatures, and the obtained product can realize the weight reduction requirement but is mostly applied to the medium and low temperature fields, and mainly applied to the weight reduction, shock absorption, magnetic field correspondence and the like in the medium and low temperature fields.

The curing and forming temperature of the high-temperature resistant polyimide composite material is higher, and the traditional interlayer weight-reducing material cannot meet the use requirement. High temperature resistant polyimide composite has obtained extensive application in aerospace field, take the hypervelocity aircraft as an example, large-scale complicated structure uses the light high temperature resistant polyimide glass bead core that can satisfy the temperature resistant requirement and probably produces bulky non-main load carrying area when replacing metal material, and this kind of regional weight reduction is prior art's blind spot, uses traditional sandwich structure, can't satisfy high temperature resistant environment demand, can bring unnecessary destruction and lead to the reduction of the life of whole material. Therefore, the interlayer core material in the prior art cannot meet the temperature resistance and cannot ensure the consistency of the matrix material, so that the overall performance of the material is not high.

Disclosure of Invention

(1) Technical problem to be solved

The embodiment of the invention provides a preparation method of a light high-temperature-resistant polyimide glass bead core material, and the obtained low-density high-temperature-resistant sandwich material can meet the use requirement of a high-temperature-resistant sandwich structure composite material, so that the core material can be used in the fields of aerospace and the like which need to use the high-temperature-resistant polyimide composite material to replace a metal structure, and the problems in the background technology are solved.

(2) Technical scheme

The embodiment of the invention provides a preparation method of a light high-temperature-resistant polyimide glass bead core material, which comprises the following steps:

(1) dissolving a diamine monomer in an organic solvent to obtain a diamine solution with the concentration of 10-60 wt%, then dissolving a blocking agent and a dianhydride monomer in the organic solvent, uniformly mixing, pouring the mixture into the diamine solution, and then carrying out polymerization reaction at 0-120 ℃ to obtain a polyimide solution with the concentration of 5-60 wt%;

(2) simultaneously adding the closed-cell glass beads and the polyimide solution obtained in the step (1) into a mechanical blending device and fully mixing to obtain a glass bead polyimide solution mixture;

(3) and (3) pouring the mixture of the glass bead and the polyimide solution obtained in the step (2) into a forming die, and curing for 1-10 hours at the temperature of 320-400 ℃ and the pressure of 0.1-5.0 MPa to obtain the light high-temperature-resistant polyimide glass bead core material.

Further, in the first step, the molar ratio of the diamine monomer, the dianhydride monomer and the end capping agent is (n + 1): n: 2, wherein n is any integer from 1 to 8.

Further, the organic solvent is one or a combination of several of methanol, ethanol, butanol, tetrahydrofuran, dioxane, N-dimethylacetamide, N-methylpyrrolidone, m-cresol and N, N-dimethylformamide.

Further, the diamine monomer is one of a BPDA monomer and a 6FDA monomer.

Further, the dianhydride monomer is one of APB, 3,4-ODA and m-PDA.

Further, the end-capping reagent is one of norbornene anhydride or phenylethynyl phthalic anhydride.

Further, the norbornene anhydride has a structural formula:

the structural formula of the phenylethynyl phthalic anhydride is as follows:

further, the mass ratio of the closed-cell glass beads to the polyimide solution is as follows: 1-70: 100.

Further, the particle size of the closed-cell glass beads is 10-250 micrometers.

Further, the mechanical blending device comprises a mixing unit and a heating unit.

(3) Advantageous effects

The invention adopts thermosetting polyimide as a resin matrix, and closed-cell glass beads as an additive to prepare the light high-temperature-resistant polyimide glass bead core material, wherein the core material has the high-temperature-resistant performance of polyimide, and simultaneously has the characteristic of low density due to the addition of the glass beads; diluting the polyimide resin by using a solvent to ensure that the glass beads can be dispersed in the resin solution at room temperature; the mechanical blending mode is used for assistance, so that the uniform dispersion of the glass beads is ensured, and the performance of each area of the obtained light high-temperature-resistant polyimide glass bead core material is stable; the whole density and performance of the light high-temperature-resistant polyimide glass bead core material can be regulated and controlled by controlling the particle size or content of the glass beads, the mechanical performance of the light high-temperature-resistant polyimide glass bead core material can be regulated and controlled by controlling the curing degree, and the light high-temperature-resistant polyimide glass bead core material with different temperature-resistant grades and different performance requirements can be obtained by combining the design of the molecular structure of the thermosetting polyimide resin; the obtained light high-temperature-resistant polyimide glass bead core material can meet the temperature resistance, simultaneously can ensure the consistency of the base material and keep the overall higher performance of the material. Therefore, the light high-temperature-resistant polyimide glass bead core material has a better application prospect in the fields of aerospace and the like which need to use a high-temperature-resistant polyimide composite material to replace a metal structure; the light high-temperature-resistant polyimide glass bead core material subjected to structural design can be used for realizing weight reduction in multiple fields suitable for polyimide resin, and the production and use cost is reduced.

Detailed Description

The following examples further describe embodiments of the present invention in detail. The following detailed description of the embodiments is provided to illustrate the principles of the invention and is not intended to limit the scope of the invention, i.e., the invention is not limited to the described embodiments.

The light high-temperature-resistant polyimide glass bead core material has a good application prospect in the fields of aerospace and the like which need to use a high-temperature-resistant polyimide composite material to replace a metal structure. In addition, the light high-temperature-resistant polyimide glass bead core material can be provided with different densities, so that weight reduction in different degrees and different mechanical property retentivity in different degrees and different resin matrixes are realized in different curing degrees, the light high-temperature-resistant polyimide glass bead core material is suitable for different temperature environments, and further, the light high-temperature-resistant polyimide glass bead core material is used for realizing weight reduction in multiple fields suitable for polyimide resin and reducing the production and use cost.

Based on the defects of the prior art, the invention provides a preparation method of a light high-temperature-resistant polyimide glass bead core material, which at least comprises the following steps:

(1) dissolving (n +1) parts of diamine monomer in an organic solvent to obtain a diamine solution with the concentration of 10-60 wt%, then dissolving 2 parts of end capping agent and n parts of dianhydride monomer in the organic solvent, uniformly mixing, and pouring the mixture into the diamine solution, namely controlling the molar ratio of the components as diamine: dianhydride: end-capping agent ═ (n + 1): n: 2, wherein n is 1-8, and then carrying out a polymerization reaction at 0-120 ℃ to obtain an amic acid (salt) oligomer solution with a concentration of 5-60% wt;

(2) simultaneously adding the closed-cell glass beads and the amic acid (salt) oligomer solution into a mechanical blending device and fully mixing, wherein the mass ratio of the closed-cell glass beads to the polyimide solution is controlled as follows: 1-70: 100;

(3) and pouring the mixture of the closed-cell glass beads and the amic acid (salt) oligomer solution into a forming die, and curing for 1-10 hours at the temperature of 320-400 ℃ and the pressure of 0.1-5.0 MPa to obtain the light high-temperature-resistant polyimide glass bead core material.

The organic solvent is one or more of methanol, ethanol, butanol, tetrahydrofuran, dioxane, N-dimethylacetamide, N-methylpyrrolidone, m-cresol and N, N-dimethylformamide. The diamine monomer is one of BPDA monomer and 6FDA monomer. The end-capping reagent is one of norbornene anhydride or phenylethynyl phthalic anhydride. The dianhydride monomer is one of APB, 3,4-ODA and m-PDA. The size of the glass bead is 10-250 microns. Wherein, the mechanical blending device comprises a mixing unit and a heating unit, and the mixing unit can adopt a mechanical blending method of stirring and blending.

The present application will be described in detail with reference to specific examples 1 to 4. It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict.