阅读说明：本技术 一种聚酰亚胺-氟聚合物绝缘复合材料、制备方法及其应用 (Polyimide-fluoropolymer insulating composite material, preparation method and application thereof ) 是由 张云 李炳健 李建革 丁荣华 宋海明 陈宇峰 黄彐全 雷伟 花金旦 郭祥 于 2019-04-12 设计创作，主要内容包括：本发明公开了一种聚酰亚胺-氟聚合物绝缘复合材料的制备方法、制备方法及其应用,方法包括以下步骤：1)将聚酰亚胺膜表面经电晕工艺处理后,涂覆氟聚合物乳液,经高温干燥、烧结后制成氟聚合物粘结层；2)将步骤1)形成的复合材料的表面通过双金属辊热压复合氟聚合物绝缘外层,制备得复合结构的聚酰亚胺-氟聚合物绝缘复合材料,复合材料包括：聚酰亚胺绝缘基层、氟聚合物粘结层和氟聚合物绝缘外层,聚酰亚胺绝缘基层的至少一侧表面通过氟聚合物粘结层与氟聚合物绝缘外层连接。通过上述方式,本发明能够集优异的耐热性能、机械性能、电气性能、防水、防油、耐刮擦、耐化学腐蚀等特性于一体,制备实施的复合体系粘接性强。(The invention discloses a preparation method, a preparation method and application of a polyimide-fluoropolymer insulating composite material, wherein the method comprises the following steps: 1) after the surface of the polyimide film is treated by a corona process, coating a fluorine polymer emulsion, and preparing a fluorine polymer bonding layer after high-temperature drying and sintering; 2) compounding the surface of the composite material formed in the step 1) with a fluoropolymer insulating outer layer through hot pressing of a bimetallic roll to prepare the polyimide-fluoropolymer insulating composite material with a composite structure, wherein the composite material comprises: the polyimide insulation substrate comprises a polyimide insulation substrate layer, a fluoropolymer bonding layer and a fluoropolymer insulation outer layer, wherein at least one side surface of the polyimide insulation substrate layer is connected with the fluoropolymer insulation outer layer through the fluoropolymer bonding layer. Through the mode, the composite material can integrate the characteristics of excellent heat resistance, mechanical property, electrical property, water resistance, oil resistance, scraping resistance, chemical corrosion resistance and the like, and the prepared and implemented composite system has strong adhesion.)

1. A preparation method of a polyimide-fluoropolymer insulating composite material is characterized by comprising the following steps:

1) After the surface of the polyimide film is treated by a corona process, coating a fluorine polymer emulsion, and preparing a fluorine polymer bonding layer after high-temperature drying and sintering;

2) compounding the surface of the composite material formed in the step 1) with a fluoropolymer insulating outer layer through hot pressing of a bimetallic roll to prepare the polyimide-fluoropolymer insulating composite material with a composite structure.

2. The method for preparing the polyimide-fluoropolymer insulation composite material according to claim 1, wherein the bimetallic roller adopts an electromagnetic heating mode, the hot pressing temperature is controlled to be 280-350 ℃, the linear speed is 5-10rpm, and the pressure is 0.5-1 MPa.

3. The method of preparing a polyimide-fluoropolymer insulation composite according to claim 1, wherein the fluoropolymer emulsion is coated to a thickness of 2 μ ι η to 50 μ ι η.

4. The polyimide-fluoropolymer insulation composite prepared by the preparation method according to any one of claims 1 to 3, comprising: the polyimide insulation substrate comprises a polyimide insulation substrate layer, a fluoropolymer bonding layer and a fluoropolymer insulation outer layer, wherein at least one side surface of the polyimide insulation substrate layer is connected with the fluoropolymer insulation outer layer through the fluoropolymer bonding layer.

5. The method of making a polyimide-fluoropolymer insulation composite of claim 4, wherein the outer fluoropolymer insulation layer comprises a Polytetrafluoroethylene (PTFE) film, a polytetrafluoroethylene/tetrafluoroethylene-hexafluoropropylene copolymer (PTFE/FEP) composite, a polytetrafluoroethylene/perfluoropropyl perfluorovinyl ether-polytetrafluoroethylene copolymer (PTFE/PFA) composite, a polytetrafluoroethylene/ethylene-tetrafluoroethylene copolymer (PTFE/ETFE) composite, or a polytetrafluoroethylene/polyvinylidene fluoride (PTFE/PVDF) composite.

6. The method for preparing the polyimide-fluoropolymer insulation composite material according to claim 4, wherein the fluoropolymer bonding layer is tetrafluoroethylene-hexafluoropropylene copolymer FEP emulsion, and the tetrafluoroethylene-hexafluoropropylene copolymer FEP/polyimide/tetrafluoroethylene-hexafluoropropylene copolymer FEP composite material is prepared by high-temperature drying and sintering.

7. The preparation method of the polyimide-fluoropolymer insulation composite material according to claim 4, wherein the upper surface and the lower surface of the polyimide insulation base layer are connected with the fluoropolymer insulation outer layer through fluoropolymer bonding layers to form the polyimide-fluoropolymer insulation composite material with a five-layer composite structure.

8. The use of the polyimide-fluoropolymer insulation composite material according to claim 4, wherein the polyimide-fluoropolymer insulation composite material is wrapped on a copper conductor, and other insulation layers are wrapped outside the polyimide-fluoropolymer insulation composite material.

9. The use of the polyimide-fluoropolymer insulation composite material according to claim 4, wherein the polyimide-fluoropolymer insulation composite material is applied to a high-frequency high-speed flexible circuit board with a low dielectric constant, the upper surface and the lower surface of the polyimide-fluoropolymer insulation composite material are subjected to hot-pressing compounding with an electrolytic copper foil, and the surfaces of the polyimide-fluoropolymer insulation composite material are subjected to circuit-making by using conductive glue or printed circuit boards.

Technical Field

The invention relates to a polyimide-fluoropolymer insulating composite material, a preparation method and application thereof.

Background

The Polyimide (PI) has a very stable aromatic heterocyclic structure in a polymer main chain, so that the polyimide has very excellent comprehensive performance, excellent mechanical property, excellent high and low temperature resistance, wide use temperature range (-200-300 ℃), excellent dielectric property, high voltage resistance, radiation resistance, corrosion resistance and excellent flame retardance. At present, the research, development and utilization of polyimide materials are listed as one of the most promising engineering plastics in the 21 st century in various countries, but the polyimide is used as an electrical insulating material, has low surface energy, is lack of self-adhesion and has poor hydrolysis resistance in a humid environment; in addition, the dielectric constant of the polyimide is 3-3.5, so that the polyimide can only be applied to the field of common insulation and is not suitable for special fields such as high-frequency high-speed flexible circuit boards with low dielectric constants, aerospace and the like.

The fluorine polymer material (such as polytetrafluoroethylene PTFE, tetrafluoroethylene-hexafluoropropylene copolymer FEP, perfluoropropyl perfluorovinyl ether-polytetrafluoroethylene copolymer PFA and ethylene-tetrafluoroethylene copolymer ETFE) not only has excellent electrical insulation, but also has lower dielectric constant and dielectric loss, can obtain the dielectric constant less than 2.5 under the high-frequency condition, and has the characteristics of high temperature resistance, water resistance, oil resistance, chemical corrosion resistance and the like. But the lapped cable film prepared by adopting the fluoropolymer material has poor scratch resistance.

Disclosure of Invention

The invention mainly solves the technical problem of providing a polyimide-fluoropolymer insulating composite material, a preparation method and application thereof, which can solve the defects of low surface energy, lack of self-adhesion, poor hydrolysis resistance in a humid environment and the like of polyimide and overcome the technical problem of compounding polytetrafluoroethylene and polyimide.

In order to solve the technical problems, the invention adopts a technical scheme that: the preparation method of the polyimide-fluoropolymer insulating composite material comprises the following steps:

1) after the surface of the polyimide film is treated by a corona process, coating a fluorine polymer emulsion, and preparing a fluorine polymer bonding layer after high-temperature drying and sintering;

2) Compounding the surface of the composite material formed in the step 1) with a fluoropolymer insulating outer layer through hot pressing of a bimetallic roll to prepare the polyimide-fluoropolymer insulating composite material with a composite structure.

In a preferred embodiment of the invention, the bimetallic roller adopts an electromagnetic heating mode, the hot pressing temperature is controlled to be 280-350 ℃, the linear speed is 5-10rpm, and the pressure is 0.5-1 MPa.

In a preferred embodiment of the present invention, the fluoropolymer emulsion is coated to a thickness of 2 μm to 50 μm.

In order to solve the technical problem, the invention adopts another technical scheme that: the polyimide-fluoropolymer insulation composite material prepared by the preparation method comprises the following steps: the polyimide insulation substrate comprises a polyimide insulation substrate layer, a fluoropolymer bonding layer and a fluoropolymer insulation outer layer, wherein at least one side surface of the polyimide insulation substrate layer is connected with the fluoropolymer insulation outer layer through the fluoropolymer bonding layer.

In a preferred embodiment of the invention, the outer fluoropolymer insulation layer comprises a polytetrafluoroethylene PTFE film, a polytetrafluoroethylene/tetrafluoroethylene-hexafluoropropylene copolymer PTFE/FEP composite, a polytetrafluoroethylene/perfluoropropyl perfluorovinyl ether-polytetrafluoroethylene copolymer PTFE/PFA composite, a polytetrafluoroethylene/ethylene-tetrafluoroethylene copolymer PTFE/ETFE composite, or a polytetrafluoroethylene/polyvinylidene fluoride PTFE/PVDF composite.

In a preferred embodiment of the present invention, the fluoropolymer bonding layer is tetrafluoroethylene-hexafluoropropylene copolymer FEP emulsion, which is dried and sintered at high temperature to form tetrafluoroethylene-hexafluoropropylene copolymer FEP/polyimide/tetrafluoroethylene-hexafluoropropylene copolymer FEP composite.

In a preferred embodiment of the invention, the upper and lower surfaces of the polyimide insulating base layer are connected with the fluoropolymer insulating outer layer through fluoropolymer bonding layers to form a polyimide-fluoropolymer insulating composite material with a five-layer composite structure.

In order to solve the technical problem, the invention adopts another technical scheme that: the application of the polyimide-fluoropolymer insulating composite material is applied to wrapping of wires and cables, the polyimide-fluoropolymer insulating composite material is wrapped on a copper conductor, and then other insulating layers are wrapped on the outer side of the polyimide-fluoropolymer insulating composite material.

In order to solve the technical problem, the invention adopts another technical scheme that: the application of the polyimide-fluoropolymer insulating composite material is provided, the polyimide-fluoropolymer insulating composite material is applied to a high-frequency high-speed flexible circuit board with a low dielectric constant, the upper surface and the lower surface of the polyimide-fluoropolymer insulating composite material are subjected to hot-pressing compounding with electrolytic copper foils, and the surfaces of the polyimide-fluoropolymer insulating composite material or a circuit is printed by using conductive glue for plate making.

The invention has the beneficial effects that: the invention integrates excellent heat resistance, mechanical property, electrical property, water resistance, oil resistance, scraping resistance, chemical corrosion resistance and other properties into a whole, overcomes the defects of low surface energy, lack of self-adhesion, poor hydrolysis resistance in a humid environment and the like of polyimide in preparation and implementation, and overcomes the difficult process of compounding polytetrafluoroethylene and polyimide and strong adhesion of a compound system; the electric constant of the high-frequency flexible printed circuit board is less than 2.5, the scratch resistance is excellent, the overall flexibility is good, and the high-frequency high-speed flexible printed circuit board is suitable for special fields of low dielectric constant, high-frequency high-speed flexible printed circuit boards, aerospace and the like.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments are briefly introduced below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without inventive efforts, wherein:

FIG. 1 is a schematic structural diagram of a preferred embodiment of the polyimide-fluoropolymer insulation composite of the present invention;

FIG. 2 is a schematic structural diagram of a preferred embodiment of the polyimide-fluoropolymer insulation composite application of FIG. 1;

FIG. 3 is a schematic diagram of another preferred embodiment of the polyimide-fluoropolymer insulation composite application shown in FIG. 1.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Referring to fig. 1, an embodiment of the present invention includes:

a polyimide-fluoropolymer insulation composite, comprising: polyimide insulating base layer 3, fluoropolymer tie coat 2, 4 and fluoropolymer insulating skin 1, 5, polyimide insulating base layer 3's at least one side surface passes through fluoropolymer tie coat 2, 4 and fluoropolymer insulating skin 1, 5 are connected.

The thickness of the polyimide-fluorine polymer insulating composite material is 50-300 μm.

In the invention, the upper and lower surfaces of the polyimide insulating base layer 3 are preferably connected with the fluoropolymer insulating outer layers 1 and 5 through the fluoropolymer bonding layers 2 and 4 to form a polyimide-fluoropolymer insulating composite material with a five-layer composite structure, as shown in fig. 1.

By adding a certain amount of fluorine-containing resin to coat the nano silica particles, a polyimide film having a low dielectric constant and high water resistance is obtained as the base layer 3.

The fluoropolymer insulating outer layers 1 and 5 comprise Polytetrafluoroethylene (PTFE) films, polytetrafluoroethylene/tetrafluoroethylene-hexafluoropropylene copolymer (PTFE)/Fluorinated Ethylene Propylene (FEP) composite materials, polytetrafluoroethylene/perfluoropropyl perfluorovinyl ether-polytetrafluoroethylene copolymer (PTFE)/PFA composite materials, polytetrafluoroethylene/ethylene-tetrafluoroethylene copolymer (PTFE)/ETFE composite materials or polytetrafluoroethylene/polyvinylidene fluoride (PTFE)/PVDF composite materials.

The fluoropolymer adhesive layers 2 and 4 are preferably tetrafluoroethylene-hexafluoropropylene copolymer FEP emulsion, and are dried and sintered at high temperature to prepare the tetrafluoroethylene-hexafluoropropylene copolymer FEP/polyimide PI/tetrafluoroethylene-hexafluoropropylene copolymer FEP composite material.

FEP, as one of the fluorine materials, functions as both an adhesive layer and an insulator. The outer fluoropolymer insulating layer plays a role in protecting the polyimide insulating base layer and resisting hydrolysis.

The polyimide-fluoropolymer insulation composite material integrates excellent heat resistance, mechanical property, electrical property, water resistance, oil resistance, scraping resistance, chemical corrosion resistance and the like. The preparation method overcomes the defects of low surface energy, lack of self-adhesion, poor hydrolysis resistance in a humid environment and the like of polyimide, overcomes the difficulty of a composite process of the fluoropolymer insulating outer layer and the polyimide, and has strong adhesion of a composite system. The dielectric constant of the high-frequency flexible printed circuit board is less than 2.5, the scratch resistance is excellent, the overall flexibility is good, and the high-frequency high-speed flexible printed circuit board is suitable for special fields of low dielectric constant high-frequency high-speed flexible printed circuit boards, aerospace and the like.

A process for preparing the insulating composite polyimide-fluoric polymer material includes such steps as