WO2022041358A1

WO2022041358A1 - Novel composite panel and production method therefor

Info

Publication number: WO2022041358A1
Application number: PCT/CN2020/116499
Authority: WO
Inventors: 尚建勋; 王婼楠; 马玉梅
Original assignee: 上海骏赐投资管理中心(有限合伙)
Priority date: 2020-08-24
Filing date: 2020-09-21
Publication date: 2022-03-03
Also published as: CN111844946A

Abstract

A composite sandwich panel and a production method therefor. The composite sandwich panel comprises: thermoplastic composite skins (1), each thermoplastic composite skin (1) being formed integrally by a fabric (2) covered by a thermoplastic material or a thermoplastic composite material, and the fabric (2) having a first side impregnated with resin and a second side not impregnated with resin; adhesive layers (3), the second sides of the fabrics (2) being close to the adhesive layers (3); and a core (4), the adhesive layers (3) being provided on the upper surface and lower surface of the core (4).

Description

A new type of composite board and its preparation method

technical field

The present disclosure relates to the field of composite material parts manufacturing, in particular to a novel composite board and a preparation method thereof.

Background technique

Aramid paper honeycomb composite material has excellent properties such as light weight and high strength, flame retardant and environmental protection, corrosion resistance and fatigue resistance, and is widely used in high-end fields such as aerospace, rail transit, and military industry. In general, aramid honeycombs are often compounded with thermoset composite skins to form a sandwich structure, which can greatly reduce product quality. It has unparalleled advantages in many aspects such as effective weight reduction, corrosion reduction, noise improvement, damping and shock absorption.

At present, composite materials formed from thermosetting prepregs have a series of weaknesses, such as long molding cycle, poor impact toughness, short storage time of prepregs, difficult to repair local damage, and poor heat and humidity resistance, and they are not easy to be recycled, and the cost of recycling is relatively high. high.

Thermoplastic materials have significant advantages such as high toughness, high impact resistance and damage tolerance, moisture and heat resistance, unlimited storage period, short molding cycle, high production efficiency, easy repair, and are recyclable.

The use of thermoplastic composite materials and aramid honeycomb composites can effectively improve the heat and humidity resistance, impact resistance, high damage tolerance, easy repair, and recyclability of aramid honeycomb composite panels without affecting the mechanical properties of the product. The raw materials are easy to store and the production efficiency is high.

At present, the composite skin of the aramid honeycomb composite panel is a thermosetting fiber composite material. Although this material can provide good mechanical properties, it has long molding cycle, poor impact toughness, short storage time of prepreg, and local damage is difficult to repair. , poor heat and humidity resistance and a series of weaknesses, and it is not easy to recycle, and the cost of recycling is high.

Although current thermoplastic composites have significant advantages such as high toughness, high impact resistance and damage tolerance, moisture and heat resistance, unlimited storage period, short molding cycle, high production efficiency, easy repair, and are recyclable. However, its material is not easy to be bonded with other materials (such as thermosetting materials, metal materials, etc.). Therefore, currently thermoplastic composites generally appear in the form of fiber-reinforced thermoplastic composites used alone or assembled with other materials, while almost no fiber-reinforced thermoplastic composites appear in sandwich composite structures (such as aramid honeycomb, aluminum honeycomb, foam, etc.). material, thermoplastic.

In addition, the problem of composite bonding of thermoplastic materials or thermoplastic composite materials with other materials is a barrier that limits its wide application, and it is also a major problem that current technology needs to break through.

SUMMARY OF THE INVENTION

By using the thermoplastic composite skin as the surface layer of the composite plate, the present disclosure effectively solves the problem that the current thermosetting composite skin composite sandwich structure has poor impact resistance, low damage tolerance, poor moisture and heat resistance, difficult to repair, and difficult to repair under the requirement of ensuring mechanical properties. Recycling issues. Thereby, the sandwich structure can be better applied under more severe conditions to promote the lightweight design and development of high-end equipment.

The present disclosure can effectively solve the problem of composite bonding of thermoplastic materials or thermoplastic composite materials and core materials by adopting a new composite process method.

In order to solve at least one of the above technical problems, the present disclosure provides a sandwich composite panel, including:

a thermoplastic composite skin, the thermoplastic composite skin is covered with a fabric and a thermoplastic composite material, the first surface of the fabric is impregnated with resin, and the second surface is not impregnated with resin;

an adhesive layer against which the second side of the fabric abuts the adhesive layer; and

A core material, the adhesive layer is provided on the upper surface and the lower surface of the core material.

In a preferred embodiment, in a thermoplastic composite skin, a fabric is treated with a portion of the fabric embedded in the thermoplastic or thermoplastic composite and a portion exposed on the skin surface.

In a preferred embodiment, a prepreg layer is further included between the fabric and the core material. Thus, better mechanical properties can be obtained.

The composition of prepreg is the common fiber fabric impregnated resin material, the fiber fabric is often glass fiber, carbon fiber, aramid fiber, etc., and the resin is usually epoxy resin, bismaleimide resin, etc. The stiffness of general thermoplastic composites is relatively weaker than that of thermoset composites. When the thermoplastic composite skin is directly compounded with the honeycomb, if its mechanical properties, flexural strength, stiffness, etc. do not meet the requirements, thermosetting prepregs can be added to reinforce the mechanical properties. For example, carbon fiber epoxy and glass fiber epoxy prepreg are thermosetting composite materials with better mechanical properties. The shortcomings of the two are compensated by the compounding of thermosetting composite materials and thermoplastic composite materials. Also sometimes the prepreg layer acts both as an adhesive layer and as reinforcement (replacing the glue film).

In a preferred embodiment, the fabric is selected from one or more of glass fiber, carbon fiber or aramid.

The above thermoplastic materials are environmentally friendly and have excellent corrosion resistance, elasticity and impact resistance, and can enhance the corrosion resistance and impact resistance of the thermoplastic composite material.

Herein, the term "thermoplastic composite material" refers to a composite material made of thermoplastic material as matrix and various fibers as reinforcing material.

In contrast to thermoset composites, the one-step curing process for thermoplastics does not require catalysts, ovens or autoclaves. This fast curing cycle is the reason why thermoplastic composites are used in high-volume production methods such as injection molding. Thermoplastic polymers do not chemically crosslink after curing, so they can be remelted and reformed. This provides unique post-forming capabilities and addresses the inability to recycle thermoset composites. In fact, many see its recyclability as the key to future growth.

Generally speaking, the heat resistance of thermoplastic composites is around 100°C. The use temperature of thermoplastic materials reinforced with glass fibers can be greatly increased. The water resistance and nodal properties of thermoplastic composites are generally better than those of thermoset composites. In addition, the technological performance of thermoplastic materials is better than that of thermosetting materials, and can be formed repeatedly, and the waste can be recycled.

Preferably, the thermoplastic composite material is a fiber-reinforced thermoplastic composite material.

In a preferred embodiment, the core material is selected from one or more of aramid honeycomb, aluminum honeycomb, and PMI foam.

In a preferred embodiment, the resin is selected from one or more of thermoplastic resins PPS, PEEK, PEKK, PC, PET, TPU, PA6, PA66, PP, PE.

In a preferred embodiment, the binder is selected from one or more of thermosetting resins and reactive polymers.

The present disclosure also provides a preparation method for preparing a sandwich composite panel, which is characterized by comprising:

The first side of the fabric is impregnated with resin, and then the first side of the fabric is combined with the thermoplastic composite material to form a bondable thermoplastic composite material skin;

Adhesive layers are arranged on the upper and lower surfaces of the cut core material;

The second surface of the fabric is not impregnated with resin, and the second surface is respectively covered on the adhesive layers on the upper surface and the lower surface of the core material;

Pressure and temperature are applied to solidify and form, and after completion, the mold is demolded to obtain a sandwich composite panel with a thermoplastic composite skin on the surface.

In a preferred embodiment, the composite molding pressure of the core material is 0.1-0.5 MPa, preferably 0.3 MPa.

In a preferred embodiment, the temperature is 60-150°C, preferably 120°C.

In a preferred embodiment, the curing molding is selected from one or more of vacuum bag molding, autoclave molding and thermocompression molding.

Compared with the prior art, the present disclosure effectively solves the problems of poor impact resistance, poor moisture and heat resistance, low damage tolerance, and difficulty in the prior art under the condition of ensuring the excellent performance of the sandwich composite panel such as light weight, high strength, and fatigue resistance. Repair, not easy to recycle the problem. When thermosetting composites are impacted, the matrix resin is prone to breakage and even the reinforcing fibers are broken. In a high temperature and high humidity environment, some defects are damaged, resulting in failures such as delamination and bagging. When a thermoplastic material or thermoplastic composite material is impacted, plastic deformation will occur, and there will be no problems such as matrix rupture and damage to the thermosetting composite material, such as delamination and bagging.

Thermoplastic materials and thermoplastic composite materials have smooth surfaces and low surface energy, and general adhesives are difficult to bond. When adhesives are used to bond plastics, thermosetting resins, and metal materials, failure may occur on the bonding surface of thermosetting composite materials and metal materials. The present disclosure proposes a new thermoplastic composite material skin, which can be effectively bonded with other materials through a fabric transition layer; a part of the fabric is embedded in the thermoplastic composite material, and a part of the fabric can be bonded with general structural glue to form a composite body , so as to realize the bonding compound of thermoplastic composite material and other materials.

Description of drawings

The accompanying drawings illustrate exemplary embodiments of the present disclosure and, together with the description, serve to explain the principles of the present disclosure, are included to provide a further understanding of the disclosure, and are incorporated in and constitute the present specification part of the manual.

FIG. 1 is a schematic diagram illustrating an exemplary embodiment of a sandwich composite panel of the present disclosure.

reference number

1. Thermoplastic composite skin;

2. Fabric;

3. Adhesive layer/(and/or prepreg layer);

4. Core material.

detailed description

The present disclosure will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the related content, but not to limit the present disclosure. In addition, it should be noted that, for the convenience of description, only the parts related to the present disclosure are shown in the drawings.

It should be noted that the embodiments of the present disclosure and the features of the embodiments may be combined with each other unless there is conflict. The present disclosure will be described in detail below with reference to the accompanying drawings and in conjunction with the embodiments.

Example

Example 1

The mesh fabric glass fiber is used to impregnate PC resin on one side, and then it is integrated with PC thermoplastic material to prepare a bondable PC thermoplastic composite skin;

Place the PC thermoplastic composite skin on the mold, with its outer surface facing the mold surface, and isolate it from the mold surface with a release film; the exposed side of the fabric not impregnated with resin is used as the bonding surface, and the adhesive layer is applied;

Lay the cut core aramid honeycomb on the film;

Lay the cut film on the core material;

Lay another thermoplastic composite skin, with the exposed side of the fabric not impregnated with resin facing down as the bonding surface, the outer surface facing outward, and isolating it from the mold surface with an isolation film;

Apply 0.3MPa pressure (preferably core material composite molding pressure) and film curing temperature of 120°C (preferably prepreg) for curing and molding (autoclave molding), and demoulding after completion to obtain a surface of PC composite material skin Sandwich composite panel.

Example 2

The mesh fabric carbon fiber is used to impregnate PEEK resin on one side, and then it is integrated with the PEEK sheet to prepare a bondable PEEK composite skin;

Place the PEEK composite skin on the mold, with its outer surface facing the mold surface, and isolate it from the mold surface with a release film; the exposed side of the fabric not impregnated with resin is used as the bonding surface, and the adhesive layer is applied;

Then lay the prepreg (reinforcing fiber: glass fiber; resin is epoxy resin);

Lay the cut core aluminum honeycomb on the prepreg;

Lay the cut prepreg on the core material;

Lay the adhesive film on the prepreg layer;

Lay another PEEK composite skin, the exposed side of the fabric not impregnated with resin is used as the bonding surface, the outer surface is facing outward, and the isolation film is used to isolate the mold surface;

Apply 0.3MPa pressure (preferably core material composite molding pressure) and film curing temperature of 130°C (preferably prepreg curing temperature) for curing and molding (hot pressing molding), and demoulding after completion to obtain a PEEK composite skin surface. Sandwich composite panel.

Comparative Example 1 is a glass fiber phenolic aramid honeycomb composite panel.

Comparative Example 2 is a glass fiber epoxy aramid honeycomb composite panel.

Impact test

Falling ball impact: steel ball diameter 50mm, weight 500g. The steel ball impacts the surface of the sample in free fall from a height of 2000mm, and the depth of the depression formed by the impact is measured and the average value is recorded.

A falling ball impact test was performed on the obtained composite panels, and the results obtained are shown in Table 1 below.

Comparative Example 1 Falling ball impact test of glass fiber phenolic aramid honeycomb composite panels.

Comparative Example 2 Falling ball impact test of glass fiber epoxy aramid honeycomb composite panels.

Table 1 The performance of the composite board falling ball impact test

As can be seen from Table 1, the thermoplastic composite material was used in Example 1, while the thermosetting composite material was used in Comparative Examples 1 and 2. The composite boards obtained in Comparative Examples 1 and 2 had obvious pits when they were impacted by falling balls. Adhesive delamination will also occur.

It can be seen that the new composite board made of thermoplastic composite materials in the present application has excellent properties such as light weight, high strength, fatigue resistance, etc., and effectively solves the problems of poor impact resistance, poor moisture and heat resistance, low damage tolerance, difficult to repair, and difficult to repair in the prior art. Recycling issues. When a thermoplastic material or thermoplastic composite material is impacted, plastic deformation will occur, and there will be no problems such as matrix rupture and damage to the thermosetting composite material, such as delamination and bagging. This technology has a simple and fast operation process, low requirements for operators, and can achieve high-efficiency, low-cost, and high-quality mass production.

The novel composite board of the present disclosure can be widely used in high-end fields such as aerospace, rail transit, and military industry, and can preferably be applied in the fields of equipment cabins and floors.

In the description of this specification, references to the terms "one embodiment/mode", "some embodiments/modes", "example", "specific example", or "some examples", etc. are intended to be combined with the description of the embodiment/mode A particular feature, structure, material, or characteristic described by way of example or example is included in at least one embodiment/mode or example of the present application. In this specification, schematic representations of the above terms are not necessarily directed to the same embodiment/mode or example. Furthermore, the particular features, structures, materials or characteristics described may be combined in any suitable manner in any one or more embodiments/means or examples. Furthermore, those skilled in the art may combine and combine the different embodiments/modes or examples described in this specification and the features of the different embodiments/modes or examples without conflicting each other.

In addition, the terms "first" and "second" are only used for descriptive purposes, and should not be construed as indicating or implying relative importance or implying the number of indicated technical features. Thus, a feature delimited with "first", "second" may expressly or implicitly include at least one of that feature. In the description of this application, "plurality" means at least two, such as two, three, etc., unless expressly and specifically defined otherwise.

Those skilled in the art should understand that the above-mentioned embodiments are only for clearly illustrating the present disclosure, rather than limiting the scope of the present disclosure. For those skilled in the art, other changes or modifications may also be made on the basis of the above disclosure, and these changes or modifications are still within the scope of the present disclosure.

Claims

A sandwich composite panel, characterized in that, comprising:

a thermoplastic composite skin, the thermoplastic composite skin is covered with a fabric and a thermoplastic composite material, the first surface of the fabric is impregnated with resin, and the second surface is not impregnated with resin;

an adhesive layer against which the second side of the fabric abuts the adhesive layer; and

A core material, the adhesive layer is provided on the upper surface and the lower surface of the core material.
The sandwich composite panel according to claim 1, wherein a prepreg layer is further included between the fabric and the core material.
The sandwich composite panel according to claim 1, wherein the fabric is selected from one or more of glass fiber, carbon fiber or aramid.
The sandwich composite panel according to claim 1, wherein the core material is selected from one or more of aramid honeycomb, aluminum honeycomb, and PMI foam.
The sandwich composite panel according to claim 1, wherein the resin is selected from one or more of thermoplastic resins PPS, PEEK, PEKK, PC, PET, TPU, PA6, PA66, PP, and PE .
The sandwich composite panel according to claim 1, wherein the adhesive is one or more of thermosetting resin and reactive polymer.
A preparation method for preparing the sandwich composite panel according to any one of claims 1-6, characterized in that, comprising:

Impregnating the first side of the fabric with resin, and then cladding the first side of the fabric and the thermoplastic composite material sheet into one body to prepare a bondable thermoplastic composite material skin;

Adhesive layers are arranged on the upper and lower surfaces of the cut core material;

The second surface of the fabric is not impregnated with resin, and the second surface is respectively covered on the adhesive layers on the upper surface and the lower surface of the core material;

Pressure and temperature are applied to solidify and form, and after completion, the mold is demolded to obtain a sandwich composite panel with a thermoplastic composite skin on the surface.
The preparation method according to claim 7, wherein the composite molding pressure of the core material is 0.1-0.5MPa.
The preparation method according to claim 7, wherein the temperature is 60-150°C.
The preparation method according to claim 7, wherein the curing molding is selected from the group consisting of vacuum bag molding, autoclave molding and hot pressing molding.