WO2022252661A1

WO2022252661A1 - Continuous long fiber-reinforced thermoplastic composite board, and preparation method therefor and use thereof

Info

Publication number: WO2022252661A1
Application number: PCT/CN2022/074306
Authority: WO
Inventors: 李园平; 徐强; 官冰; 刘修才
Original assignee: 上海凯赛生物技术股份有限公司; Cibt美国公司; 凯赛(太原)生物材料有限公司; 山西合成生物研究院有限公司
Priority date: 2021-05-31
Filing date: 2022-01-27
Publication date: 2022-12-08
Also published as: CN113232384A

Abstract

A continuous long fiber-reinforced thermoplastic composite board, and a preparation method therefor and an application thereof. The continuous long fiber-reinforced thermoplastic composite board comprises m layers of prepreg tapes A and n layers of prepreg tapes B, and the prepreg tapes A are arranged on the outer layer, wherein m≥2, n≥1, and m and n are integers; the prepreg tapes A are continuous long fiber-reinforced long carbon chain polyamide resin unidirectional prepreg tapes that comprise continuous long fibers and long carbon chain polyamide resins; and the prepreg tapes B are continuous long fiber-reinforced short carbon chain polyamide resin unidirectional prepreg tapes that comprise continuous long fibers and short carbon chain polyamide resins. The composite board has the advantages of being low in water absorption, excellent in mechanical properties, smooth in appearance, reliable in performance and practical; moreover, the preparation process is simple, the time consumed is short, the production efficiency is high, and the cost is low.

Description

Continuous long fiber reinforced thermoplastic composite sheet and its preparation method and use

technical field

The invention relates to a continuous long fiber reinforced thermoplastic composite board and its preparation method and application.

Background technique

Continuous long fiber reinforced thermoplastic composite (CFRT) is a composite material manufactured by special process with continuous fiber as reinforcement material and thermoplastic resin as matrix. Compared with short glass fiber reinforced thermoplastic composites (SFRT), CFRT has superior performance, better mechanical properties, recyclability, light weight and low cost. It is one of the polymer composite materials that has attracted much attention in the past ten years. At present, CFRT (such as continuous long fiber reinforced thermoplastic composite sheet) is mainly used in automobiles, wind power blades, electronics, home appliances, communications, machinery, chemicals, military industry, sports equipment, medical equipment and other fields, especially in the special plastic market for auto parts The application development potential of PP is very huge, the development is relatively rapid, the application is extensive, and there are many types, among which long glass fiber reinforced polypropylene (PP/LGF) composite materials are the most common. However, the strength of long glass fiber reinforced polypropylene is low, and the secondary molding of composite materials is difficult and cannot be recycled. The continuous long fiber reinforced polyamide composite material has high strength, but because polyamide itself contains a certain amount of amide bonds of polar groups, it is easy to form a hydrogen bond structure with water molecules, which will inevitably reduce the hydrogen bond density of the interaction between macromolecular chains , resulting in a decrease in the strength of the material. Therefore, there is an urgent need to prepare a continuous long fiber reinforced thermoplastic composite material that can simultaneously have high mechanical properties and low water absorption.

Continuous fiber reinforced thermoplastic prepreg tape is an intermediate used to prepare continuous fiber reinforced thermoplastic composite materials. Its preparation process mainly includes melt impregnation method, solution impregnation method and mixed fiber method.

The current techniques for preparing thermoplastic composite materials include injection molding, thermocompression molding, and pultrusion molding. Among them, the injection molding process is currently the most important molding process for the preparation of thermoplastic composites due to its advantages of high stability, automation, and high efficiency. It is also the most widely used molding process at present, but the glass fiber retention length of this method is short. The thermal compression molding process has the advantages of simple structure, good thermal stability and diversified product shapes, and is one of the more commonly used molding processes for preparing thermoplastic composite materials. The pultrusion molding process is a molding process for preparing continuous long fiber reinforced thermoplastic composites (CFRT) by pulling fiber rovings under external force through impregnation, curing, and cutting processes. After molding, the cross section of the material is fixed and continuous production of materials is realized.

Contents of the invention

In order to overcome the defect that continuous long fiber reinforced thermoplastic composite materials are difficult to simultaneously have good mechanical properties and low water absorption in the prior art, the present invention provides a continuous long fiber reinforced thermoplastic composite sheet and its preparation method and application. The continuous long fiber reinforced thermoplastic composite board provided by the invention has good mechanical properties and low water absorption, and the preparation method is simple in process and low in cost.

The present invention solves the above technical problems through the following technical solutions:

A continuous long fiber reinforced thermoplastic composite sheet, which includes m layers of prepreg A and n layers of prepreg B, and the outer layer is the prepreg A; wherein, m≥2, n≥1, and m and n is an integer;

The prepreg tape A is a continuous long fiber reinforced long carbon chain polyamide resin unidirectional prepreg tape, which includes continuous long fibers and long carbon chain polyamide resin;

The prepreg tape B is a continuous long fiber reinforced short carbon chain polyamide resin unidirectional prepreg tape, which includes continuous long fiber and short carbon chain polyamide resin.

In the present invention, the sum of the values of m and n may be 3-100, such as 4-66 or 20-66.

In the present invention, the n can be 1-98, such as 4, 6, 8 or 10.

In the present invention, preferably, the continuous long fiber reinforced thermoplastic composite sheet includes m ₁ A-[n ₁ Bm ₂ An ₂ B]-m ₃ A, wherein, m=m ₁ +m ₂ +m ₃ , m ₁ ≥1, m ₂ ≥0, m ₃ ≥1; n=n ₁ +n ₂ , n ₁ ≥0, n ₂ ≥0, and n ₁ and n ₂ are not 0 at the same time; m ₁ , m ₂ , m ₃ , n ₁ and n ₂ are all integers. Among them, "-" indicates that the prepreg tapes are adjacent, for example, "AB" indicates that a layer of prepreg A is adjacent to a layer of prepreg B.

Wherein, for example, the values of m ₁ , m ₂ , m ₃ , n ₁ and n ₂ are 1, 0, 1, 3 and 3 respectively, that is, the continuous long fiber reinforced thermoplastic composite sheet includes A-[6B] -A.

Or, for example, the values of m1, m2, m3, n1 and n2 are 2, 0, 2, 2 and 2 respectively, that is, the continuous long fiber reinforced thermoplastic composite sheet includes 2A-[4B]-2A.

Or, for example, the values of m1, m2, m3, n1 and n2 are 1, 0, 1, 4 and 4 respectively, that is, the continuous long fiber reinforced thermoplastic composite sheet includes A-[8B]-A.

Or, for example, the values of m1, m2, m3, n1 and n2 are 2, 0, 2, 3 and 3 respectively, that is, the continuous long fiber reinforced thermoplastic composite sheet includes 2A-[6B]-2A.

In the present invention, preferably, the prepregs B are each independently selected from the same or different continuous long fiber reinforced short carbon chain polyamide resin unidirectional prepregs, and the prepregs A are each independently selected from The same or different continuous long fiber reinforced long carbon chain polyamide resin unidirectional prepreg tape.

In the present invention, the thickness of the prepreg tape A is preferably 0.15-0.5mm, further 0.21-0.33mm, such as 0.23mm, 0.27mm, 0.28mm, 0.31mm, 0.32mm or 0.33mm.

In the present invention, the thickness of the prepreg tape B is preferably 0.15-0.5mm, further 0.21-0.33mm, such as 0.24mm, 0.31mm, 0.32mm or 0.33mm.

In the present invention, the total thickness of the continuous long fiber reinforced thermoplastic composite sheet is preferably >0.5mm, such as 10mm, and the thickness can be molded and composited according to specific products.

In the present invention, the layering method between layers in the continuous long fiber reinforced thermoplastic composite sheet may be parallel layering or cross layering. The parallel layup means that the layers are laid in the same direction; the cross layup means that the layers are cross laid at a certain angle.

The crossing manner of the cross-laminated layer may be 0°-90° crossing, for example, 45° crossing, 90° crossing.

Preferably, the crossing manner of the cross-laminated layers may be greater than 0° to less than or equal to 90° crossing.

In the present invention, the long carbon chain polyamide resin generally refers to the polyamide obtained by the polymerization of a dibasic acid with a methylene group between two carboxyl groups having 10 or more carbon atoms (mainly referring to pentamethylene diamine). amides. The short carbon chain polyamide resin generally refers to a polyamide obtained by polymerizing dibasic amine (mainly pentamethylenediamine) and a dibasic acid whose methylene group between two carboxyl groups has less than 10 carbon atoms.

In the present invention, the short carbon chain polyamide resin may be commercially available short carbon chain polyamide resin in the field, preferably purchased from Cathay (Jinxiang) Biomaterials Co., Ltd.

In the present invention, the short carbon chain polyamide resin is preferably a short carbon chain bio-based polyamide resin.

Among them, bio-based polyamide resins generally refer to polyamide resins obtained by using renewable resources such as corn and castor as raw materials, preparing diamines through microbial methods, and then polymerizing with dibasic acids. Preferably, the dibasic acid is also prepared by microbial methods.

In the present invention, the short carbon chain polyamide resin is preferably polyamide 56, referred to as PA56.

Wherein, the PA56 preferably has the following characteristics:

The relative viscosity is 1.9-2.7, such as 2.29;

The content of terminal amino group is 42-60mmol/kg, such as 55mmol/kg;

Melting point 252-255°C, for example 253°C;

The raw material monomers are pentamethylenediamine and adipic acid, and the bio-based content is 43%-46%.

In the present invention, the long carbon chain polyamide resin may be commercially available long carbon chain polyamide resin in the field, preferably purchased from Cathay (Jinxiang) Biomaterials Co., Ltd.

In the present invention, the long carbon chain polyamide resin is preferably a long carbon chain bio-based polyamide resin.

In the present invention, the long carbon chain polyamide resin is preferably selected from one or more of PA510, PA511, PA512, PA513, PA514, PA515, PA516, PA517 and PA518.

Preferably, the PA510 raw material monomers are pentamethylenediamine and sebacic acid prepared by biological fermentation; wherein the PA511 raw material monomers are pentamethylenediamine and undecanedioic acid prepared by biological fermentation; wherein PA512 The raw material monomers are pentanediamine and dodecanedioic acid prepared by biological fermentation; the raw material monomers of PA513 are pentanediamine and tridecanedioic acid prepared by biological fermentation; the raw material monomers of PA514 are Pentylenediamine and tetradecanedioic acid prepared by biological fermentation; among them, PA515 raw material monomers are pentanediamine and pentadecanedioic acid prepared by biological fermentation; among them, PA516 raw material monomers are prepared by biological fermentation pentanediamine and hexadecandioic acid; PA517 raw material monomers are pentanediamine and heptadecandioic acid prepared by biological fermentation; among them, PA518 raw material monomers are pentanediamine prepared by biological fermentation Diamine and octadecandioic acid.

Wherein, the long carbon chain polyamide resin preferably has the following characteristics:

Relative viscosity 1.8-2.7, preferably 2.1-2.6, such as 2.25, 2.32, 2.38, 2.46 or 2.51;

The content of terminal amino group is 40-60mmol/kg, further 42-60mmol/kg;

Melting point 170°C-320°C, preferably 180-230°C, for example 191, 197, 210 or 217°C;

The biobased content is between 29% and 100%, for example 29.6, 32.3, 33.8 or 45%.

The bio-based content is the content of the corresponding structural units of monomers prepared from raw materials derived from biomass in polyamides. Biomass is a variety of organisms formed through photosynthesis. As one of the monomers of polyamide 56, pentamethylenediamine can be obtained by decarboxylation of lysine fermented from corn. Obtained by ASTM D6866, the standard method for detection of biobased content.

In the present invention, the relative viscosity is measured by Ubbelohde viscometer concentrated sulfuric acid method. The terminal amino content is determined by the following method: after dissolving the sample with trifluoroethanol, titrate with hydrochloric acid standard solution and sodium hydroxide standard solution respectively, and calculate.

In the present invention, the continuous long fiber generally means that the theoretical value of the retained length of the fiber is consistent with that of the product, that is, the retained length of the fiber = the length of the product.

In the present invention, the continuous long fibers may be conventional and commercially available continuous long fibers in this field.

In the present invention, the type of the continuous long fiber can be conventional in the field, such as carbon fiber, glass fiber, basalt fiber or aramid fiber.

Preferably, the continuous long fiber is a continuous long glass fiber, and the diameter of a single filament may be 8-15 μm, preferably 8-10 μm. The linear density of the continuous long glass fibers may be 1000-3600Tex, preferably 1200Tex, 2400Tex. The continuous long glass fiber is, for example, a continuous long glass fiber with a specification of 1200 Tex purchased from Owens Corning (OC) or a continuous long glass fiber with a specification of 2400 Tex purchased from Jushi.

Preferably, the continuous long fibers are continuous long carbon fibers. The continuous long carbon fibers are preferably polyacrylonitrile carbon fibers. The number of monofilaments of the continuous long carbon fiber can be 20000-30000, preferably 12000 (12K), 24000 (24K). The monofilament diameter of the continuous long carbon fiber may be 5-10 μm, preferably 6-8 μm. The continuous long carbon fiber is, for example, Toray T700 with a specification of 24K, or Guangwei composite continuous long carbon fiber 700S with a specification of 12K or 24K.

In the present invention, in the prepreg tape A, the mass percentage of the continuous long fibers is preferably 40-80wt%, more preferably 60-70wt%, such as 50.1wt%, 60.5wt%, 62.1wt% %, 62.8wt% or 51.3wt%, the mass percentage means that the mass of the continuous long fiber accounts for the mass of the prepreg tape A.

In the present invention, the mass percentage of the continuous long fibers in the prepreg tape B is preferably 40-80%, more preferably 60-70%, such as 50.4wt% or 61.3wt%. The percentage means that the mass of the continuous long fibers accounts for the mass of the prepreg B.

In the present invention, preferably, the water content of the prepreg tape A is lower than 2000ppm, more preferably lower than 1200ppm, such as 100-1200ppm, or 500-1000ppm.

In the present invention, preferably, the water content of the prepreg tape B is lower than 2000ppm, more preferably lower than 1200ppm, such as 100-1200ppm, or 500-1000ppm.

The method of measuring the water content is as follows: Take 1g of the prepreg sample and measure it with a Karl Fischer moisture analyzer. The detection temperature is 200°C and the detection time is 20 minutes.

In the present invention, preferably, the short carbon chain polyamide resin is PA56, and the long carbon chain polyamide resin is any one or more of PA510, PA511, PA512, PA513, PA514, PA515 and PA516.

In the present invention, preferably, the prepreg A includes continuous long glass fiber and long carbon chain polyamide resin, and the long carbon chain polyamide resin is PA510, PA511, PA512, PA513, PA514, PA515 and PA516 Any one or more of them, more preferably, the prepreg tape A is a continuous long glass fiber reinforced long carbon chain polyamide thermoplastic unidirectional prepreg tape.

In the present invention, preferably, the prepreg tape A includes continuous long carbon fiber and long carbon chain polyamide resin, and the long carbon chain polyamide resin is PA510, PA511, PA512, PA513, PA514, PA515 and PA516 Any one or more, more preferably the prepreg tape A is continuous long carbon fiber reinforced long carbon chain polyamide thermoplastic unidirectional prepreg tape.

In the present invention, preferably, the prepreg B includes continuous long glass fibers and PA56, more preferably the prepreg B is a continuous long glass fiber reinforced PA56 unidirectional prepreg.

In the present invention, preferably, the prepreg B includes continuous long carbon fibers and PA56, more preferably the prepreg B is a continuous long carbon fiber reinforced PA56 unidirectional prepreg.

In a preferred embodiment of the present invention, in the continuous long fiber reinforced thermoplastic composite sheet, the prepreg tape A is a continuous long glass fiber reinforced long carbon chain polyamide unidirectional prepreg tape, and the prepreg tape B is continuous long glass fiber reinforced PA56 unidirectional prepreg tape.

For example: in the continuous long fiber reinforced thermoplastic composite sheet, the prepreg tape A is a continuous long glass fiber reinforced PA513 unidirectional prepreg tape, and the prepreg tape B is a continuous long glass fiber reinforced PA56 unidirectional prepreg tape .

For example: in the continuous long fiber reinforced thermoplastic composite sheet, the prepreg tape A is a continuous long glass fiber reinforced PA510 unidirectional prepreg tape, and the prepreg tape B is a continuous long glass fiber reinforced PA56 unidirectional prepreg tape .

For example: in the continuous long fiber reinforced thermoplastic composite sheet, the prepreg tape A is a continuous long glass fiber reinforced PA512 unidirectional prepreg tape, and the prepreg tape B is a continuous long glass fiber reinforced PA56 unidirectional prepreg tape .

For example: in the continuous long fiber reinforced thermoplastic composite sheet, the prepreg tape A is a continuous long glass fiber reinforced PA515 unidirectional prepreg tape, and the prepreg tape B is a continuous long glass fiber reinforced PA56 unidirectional prepreg tape .

In a preferred embodiment of the present invention, in the continuous long fiber reinforced thermoplastic composite sheet, the prepreg tape A is a continuous long carbon fiber reinforced long carbon chain polyamide unidirectional prepreg tape, and the prepreg tape B It is a continuous long carbon fiber reinforced PA56 unidirectional prepreg tape.

For example: in the continuous long fiber reinforced thermoplastic composite sheet, the prepreg tape A is a continuous long carbon fiber reinforced PA510 unidirectional prepreg tape, and the prepreg tape B is a continuous long carbon fiber reinforced PA56 unidirectional prepreg tape.

The present invention also provides a method for preparing the aforementioned continuous long fiber reinforced thermoplastic composite sheet, which includes the following steps: laminating the prepreg tape B and the prepreg tape A, and compression molding to obtain the composite sheet.

In the present invention, the layering method can be a conventional layering method in the field, such as cross-layering or parallel layering.

Wherein, the angle of the cross-laminated layers may be 0° and 90°, or 45°.

In the present invention, it is preferred to further include the step of drying the prepreg tape before the layer laying. Reducing the moisture content of the material by drying can prevent excessive air bubbles during the molding process.

Wherein, the drying operation may be a conventional drying operation in the art, such as vacuum drying.

The drying temperature is preferably 85-120°C, such as 105°C.

The drying time is preferably 4-25 hours, further 15-24 hours, such as 15 hours, 20 hours or 24 hours.

In the present invention, the equipment used for the compression molding can be the equipment conventionally used in the field for molding, such as a molding machine, and the molding machine can be a double-steel belt molding compound machine.

In the present invention, the compression molding temperature is preferably 5-10°C higher than the melting point of the short carbon chain polyamide resin, preferably 190-310°C, more preferably 250-310°C, for example 260°C or 278°C.

In the present invention, the compression molding pressure is preferably 1-5 MPa, such as 2-3 MPa.

In the present invention, the compression molding method may be a conventional compression molding method in the art, such as continuous compression molding or direct compression molding.

Wherein, when the compression molding method is continuous compression molding, the step of continuous automatic layer laying can be included according to the conventional practice in the field.

Wherein, when the compression molding method is direct compression molding, the direct compression molding may include the steps of preheating, degassing, pressure maintaining and/or cooling according to the routine in the art.

The preheating time is preferably 3-8 minutes, such as 5 minutes.

The number of exhaust gas is preferably 3-6 times, for example 3 times.

The time for maintaining the pressure is preferably 5-10 minutes, such as 8 minutes.

The cooling rate is preferably 5-20°C/min, such as 15°C/min. The temperature after cooling is preferably room temperature. In the present invention, the room temperature generally refers to 20±5°C.

In the present invention, the prepreg tape A and the prepreg tape B are preferably prepared by a melt impregnation method.

Wherein, the melt impregnation method may be a conventional melt impregnation method in the art.

Preferably, the melt impregnation method comprises the steps of:

S1, extruding the polyamide resin composition, so that the extruded melt enters the dipping die; wherein, the polyamide resin composition includes the long carbon chain polyamide resin or the short carbon chain polyamide resin;

S2, introducing the continuous long fiber into the impregnation die, impregnating the melt and the continuous long fiber;

S3. Molding, cooling, drawing and winding the impregnated continuous long fibers to obtain the prepreg A or the prepreg B.

Wherein, by adjusting the extruding speed and the winding speed, the mass percentage of the continuous long fiber in the prepreg tape is controlled.

Wherein, preferably, the polyamide resin composition further includes additives.

The additives preferably include one or more of antioxidants, lubricants, compatibilizers and coupling agents.

The antioxidant is preferably selected from one or more of antioxidant 168, antioxidant 1098, antioxidant 1010 and antioxidant S9228. Wherein, the lubricant preferably includes the external lubricant WAXC and the internal lubricant WAXE. Wherein, the compatibilizer can be selected from PP-g-MAH (maleic anhydride grafted on polypropylene), POE-g-MAH (maleic anhydride grafted on ethylene octene copolymer), POE-g - one or more of GMA (glycidyl methacrylate grafted on ethylene octene copolymer) and EPDM-g-MAH (maleic anhydride grafted on ethylene propylene diene rubber). Wherein, the coupling agent can be selected from one or more of coupling agent KH550, coupling agent KH560 and coupling agent KH570.

Unless otherwise specified, the parts in the present invention are based on parts by weight or parts by mass. Wherein, more preferably, the polyamide resin composition includes the following components in parts by weight: 81.8-99.8 parts of the long carbon chain polyamide resin or the short carbon chain polyamide resin, 0.2-1.6 parts of antioxidant parts, lubricant 0-0.8 parts, compatibilizer 0-15 parts and coupling agent 0-0.8 parts.

In certain embodiments, the polyamide resin composition includes the following components in parts by weight: 90-95 parts of the long carbon chain polyamide resin, 0.4-0.6 parts of antioxidant, 0.3-0.5 parts of lubricant, 4-8 parts of compatibilizer and 0.4-0.5 parts of coupling agent.

For example: the polyamide resin composition includes the following components in parts by weight: the long carbon chain polyamide resin: 94.5 parts, antioxidant 1098: 0.3 parts, antioxidant 168: 0.3 parts, internal lubricant WAXE: 0.2 parts parts, external lubricant WAXC: 0.2 parts, compatibilizer POE-g-MAH: 4 parts, coupling agent KH550: 0.5 parts.

In certain embodiments, the polyamide resin composition includes the following components in parts by weight: 90.5-93 parts of the short carbon chain polyamide resin, 10980.2-0.4 parts of antioxidants, 1680.2-0.4 parts of antioxidants, 0.2-0.3 parts of internal lubricant WAXE, 0.2-0.3 parts of external lubricant WAXC, 6-8 parts of compatibilizer and 0.3-0.6 parts of silane coupling agent.

For example: the polyamide resin composition raw material includes the following components in parts by weight: PA56: 90.5 parts, antioxidant 1098: 0.4 parts, antioxidant 168: 0.4 parts, internal lubricant WAXE: 0.2 parts, external lubricant WAXC : 0.2 parts, compatibilizer POE-g-MAH: 8 parts, coupling agent KH560: 0.3 parts.

Another example: the polyamide resin composition raw material includes the following components in parts by weight: PA56: 90.5 parts, antioxidant 1098: 0.3 parts, antioxidant 168: 0.3 parts, internal lubricant WAXE: 0.2 parts, external lubricant WAXC: 0.2 parts, compatibilizer POE-g-MAH: 8 parts, coupling agent KH560: 0.5 parts.

Wherein, in step S1, before extruding the polyamide resin composition, preferably, the following step is further included: mixing the polyamide resin composition. The mixing can be stirring and mixing; the equipment for stirring and mixing can be a high-speed mixer.

Wherein, in step S1, the extruding can be carried out using a conventional twin-screw extruder or single-screw extruder in the art, preferably a twin-screw extruder. Wherein, the aspect ratio of the twin-screw extruder is preferably 1:36.

In step S1, the extrusion temperature may be 170-340°C.

When a twin-screw extruder is used, the twin-screw extruder adopts an eight-zone heating mode. Preferably, the temperatures from the first zone to the eighth zone (along the direction from feeding to the head) are 195-260°C, 255- 305°C, 255-325°C, 255-325°C, 255-325°C, 255-325°C, 255-325°C, 255-325°C.

In some specific embodiments, the temperatures in Zone 1 to Zone 8 (along the direction from feeding to the head) are 240°C, 290°C, 300°C, 300°C, 300°C, 300°C, 300°C, 300°C.

In some specific embodiments, the temperatures in Zone 1 to Zone 8 (along the direction from feeding to the machine head) are 210°C, 270°C, 270°C, 270°C, 270°C, 270°C, 270°C, and 280°C.

Wherein, in step S1, expressed by the screw speed, the extrusion speed is 200-600 rpm, such as 400 rpm.

Wherein, in step S1, the step of filtering is preferably further included after the extrusion. The filtration can be performed by using a conventional melt filter in the art. Preferably, when a twin-screw extruder is used, the temperature of the melt filter is within the range of 0-15° C. above and below the eight-zone temperature of the twin-screw extruder.

Wherein, in step S1, the dipping die head can be a conventional die head in the field. The width of the dipping die is preferably 100-650mm.

Wherein, the temperature of the dipping die may be 240-335°C, such as 295 or 300°C. Preferably, when a twin-screw extruder is used, the temperature of the dipping die is within the range of 0-15°C above and below the eight-zone temperature of the twin-screw extruder.

Wherein, in step S2, the introduction preferably includes the following process: the continuous long fiber is unwound from the yarn guide frame through the tension controller, passes through the yarn dividing frame, and enters the yarn spreading system, so that the continuous long fiber Each tow is fully unfolded, then enters the yarn drying device for preheating, and then enters the impregnation die to impregnate the continuous long fibers with the melt. Wherein, the temperature of the yarn drying device is preferably 70-400°C.

In step S3, the molding and cooling can be carried out using conventional roller presses in the field, preferably four-rollers. The temperature of the internal circulating water of the four-roll machine may be 60-90°C. The traction can be carried out using a conventional traction device in the field, in which further cooling and edge trimming are performed. The traction speed of the traction can be 5-15m/min. The winding can be carried out using a conventional winding device in the field, preferably an automatic winding machine.

The present invention also provides the use of the aforementioned continuous long fiber reinforced thermoplastic composite plate in plastic products. Wherein, the plastic products preferably include plastic products in auto parts.

The positive progress effect of the present invention is: the present invention uses the continuous long fiber reinforced polyamide prepreg tape as a molded interlayer, fully utilizes the performance characteristics of bio-based polyamide, and polyamide is used as a resin matrix to connect the continuous long fibers with excellent performance. Together, a continuous long fiber reinforced thermoplastic composite sheet with low water absorption, excellent mechanical properties, smooth appearance, reliable performance and practicality is prepared.

The preparation method of the invention adopts a mold pressing composite process, which has the advantages of simple process, short time consumption, high production efficiency and low cost. The present invention can also prepare unidirectional prepreg tape by melt impregnation method, so that each monofilament in the continuous long fiber can be impregnated by resin, and the effect of impregnation is uniform; a unidirectional prepreg tape with a thickness of 0.15-0.5mm can be prepared. Dip tape can be molded or wound, allowing more freedom in production design. In addition, the present invention can also change the orientation of the long fibers in the composite board by adjusting the different placement directions of the prepreg tape, improve the impact resistance of the composite board against forces in different directions, and adjust the number of layers of the prepreg tape to adjust the composite board. thickness to suit different applications.

Description of drawings

Figure 1 is a schematic structural view of the continuous long fiber reinforced thermoplastic composite sheet 2A-[4B]-2A prepared in Example 2.

Fig. 2 is a schematic structural view of the continuous long fiber reinforced thermoplastic composite sheet A-[6B]-A prepared in Example 4.

Reference signs:

1-2A, A is continuous long glass fiber reinforced PA513 unidirectional prepreg tape;

2-4B, B is continuous long glass fiber reinforced PA56 unidirectional prepreg tape;

3-A, A is continuous long glass fiber reinforced PA512 unidirectional prepreg tape;

4-6B, B is continuous long glass fiber reinforced PA56 unidirectional prepreg tape.

Detailed ways

The present invention is further illustrated below by means of examples, but the present invention is not limited to the scope of the examples.

In the following examples, the raw materials were purchased from the following sources: bio-based polyamide resins PA56, PA510, PA512, PA513 and PA515 were purchased from Cathay (Jinxiang) Biomaterials Co., Ltd. PA6 was purchased from Guangzhou Xinhui Meida Nylon Co., Ltd. The continuous long glass fiber was purchased from Owens Corning (OC), and the specification was 1200Tex. Continuous carbon fiber was purchased from Toray Group T700 with a specification of 24K.

Among them, the characteristics of each polyamide resin are as follows:

The relative viscosity of PA56 is 2.29, the terminal amino group content is 55mmol/kg, the melting point is 253°C, and the bio-based content is 45%;

The relative viscosity of PA510 is 2.51, the terminal amino group content is 54mmol/kg, the melting point is 217°C, and the bio-based content is 100%;

The relative viscosity of PA512 is 2.32, the terminal amino group content is 56mmol/kg, the melting point is 210°C, and the bio-based content is 33.8%;

The relative viscosity of PA513 is 2.38, the terminal amino group content is 41mmol/kg, the melting point is 197°C, and the bio-based content is 32.3%;

The relative viscosity of PA515 is 2.25, the terminal amino group content is 51mmol/kg, the melting point is 191°C, and the bio-based content is 29.6%;

The relative viscosity of PA6 is 2.46, the terminal amino group content is 54mmol/kg, the melting point is 223°C, and it does not contain bio-based.

Wherein, the relative viscosity is measured by Ubbelohde viscometer concentrated sulfuric acid method. The biobased content is measured by carbon 14, for example, obtained by ASTM D6866, a standard method for detection of biobased content.

Release paper was purchased from Shandong Shenghe Paper Plastic Packaging Co., Ltd.; release cloth was purchased from Taiwei New Composite Materials Co., Ltd.

The unidirectional prepreg tapes in the following examples and comparative examples are all prepared by the melt impregnation method, and the preparation methods refer to the following preparation examples 1-4.

Preparation example 1 Preparation of continuous long glass fiber reinforced PA56 unidirectional prepreg tape:

1. Use a twin-screw extruder to extrude the polyamide 56 resin composition, and the extruded melt is filtered by a melt filter and enters the impregnation die; wherein:

The raw materials of the polyamide 56 resin composition include the following components in parts by weight: PA56: 90.5 parts, antioxidant 1098: 0.4 parts, antioxidant 168: 0.4 parts, internal lubricant WAXE: 0.2 parts, external lubricant WAXC: 0.2 parts , compatibilizer POE-g-MAH: 8 parts, coupling agent KH560: 0.3 parts, add the above components into a high-speed mixer and mix to obtain a polyamide 56 resin composition;

The twin-screw extruder adopts an eight-zone heating mode, and the temperatures from zone one to zone eight (along the direction of feeding to the machine head) are 240°C, 290°C, 300°C, 300°C, 300°C, 300°C, 300°C, 300°C ℃;

The screw speed is 400rpm; the aspect ratio of the twin-screw extruder is 1:36;

The temperature of the melt filter was 300°C; the temperature of the dipping die was 300°C.

2. Unwind the continuous long glass fiber from the yarn guide frame through the tension controller, pass through the yarn dividing frame, and enter the yarn spreading system to fully expand each tow, and then enter the yarn drying device for preheating and drying The device is set at a temperature of 85°C, and then enters the impregnation die, where the continuous long glass fiber is impregnated with the melt;

3. The impregnated continuous long glass fiber is shaped and cooled by a four-roller machine, wherein the temperature of the circulating water in the four-roller machine is set to 80°C;

Then enter the traction device for further cooling and trimming, the traction speed is 8m/min;

Finally, it enters into an automatic winder and is wound into rolls, and the winding speed is 8m/min.

During the preparation process, the screw speed of the twin-screw extruder and the winding speed of the automatic winder are controlled to ensure that the weight fraction ratio of the continuous long glass fiber and polyamide 56 resin composition is 65:35, and the continuous long glass fiber reinforced PA56 unidirectional prepreg tape.

4. Prepreg tape treatment: place the prepreg tape obtained in step 3 in a vacuum drying oven at 105°C for 15 hours to vacuum dry to reduce the moisture content of the prepreg tape to 500ppm.

Preparation Example 2 Preparation of continuous long carbon fiber reinforced PA56 unidirectional prepreg tape:

The parts by weight of the raw materials of the polyamide 56 resin composition include the following components: PA56: 90.5 parts, antioxidant 1098: 0.3 parts, antioxidant 168: 0.3 parts, internal lubricant WAXE: 0.2 parts, external lubricant WAXC: 0.2 parts , Compatibilizer POE-g-MAH: 8 parts, coupling agent KH560: 0.5 parts. Add the above components into a high-speed mixer and mix to obtain a polyamide 56 resin composition;

The screw speed is 400r/min; the aspect ratio of the twin-screw extruder is 1:36;

The temperature of the melt filter is 300°C; the temperature of the die is 300°C.

2. The continuous long carbon fiber passes through the tension controller, unwinds from the yarn guide frame, passes through the yarn dividing frame, and enters the yarn spreading system to fully expand each tow, and then enters the yarn drying device for preheating, and the yarn drying device Set the temperature to 250°C, and then enter the impregnation die, where the continuous long carbon fiber is impregnated with the melt;

3. Molding and cooling the impregnated continuous long carbon fiber through a four-roller machine, wherein the temperature of the circulating water in the four-roller machine is set to 80°C;

During the preparation process, the screw speed of the twin-screw extruder and the winding speed of the automatic winder were controlled to ensure that the weight fraction ratio of the continuous long carbon fiber and the polyamide 56 resin composition was 65:35, and the continuous long carbon fiber reinforced PA56 sheet was obtained. to the prepreg tape.

Preparation Example 3 Preparation of continuous long glass fiber reinforced long carbon chain bio-based polyamide unidirectional prepreg tape:

The long carbon chain bio-based polyamide includes PA513, PA510, PA512 or PA515.

1. Use a twin-screw extruder to extrude the long carbon chain bio-based polyamide resin composition, and the extruded melt is filtered by a melt filter and enters the impregnation die; wherein:

The parts by weight of the long carbon chain bio-based polyamide composition raw materials include the following components: long carbon chain bio-based polyamide: 94.5 parts, antioxidant 1098: 0.3 parts, antioxidant 168: 0.3 parts, internal lubricant WAXE: 0.2 parts, external lubricant WAXC: 0.2 parts, compatibilizer POE-g-MAH: 4 parts, coupling agent KH550: 0.5 parts. adding the above components into a high-speed mixer and mixing to obtain a long carbon chain bio-based polyamide composition;

The twin-screw extruder adopts eight-zone heating mode, and the temperatures from zone one to zone eight (along the direction of feeding to the head) are 210°C, 270°C, 270°C, 270°C, 270°C, 270°C, 270°C, 280°C ℃;

The screw speed is 400rpm; the aspect ratio of the twin-screw extruder is 1:36;

The temperature of the melt filter was 290°C; the temperature of the die was 295°C.

3. Molding and cooling the impregnated continuous long glass fiber through a four-roller machine, wherein the temperature of the circulating water in the four-roller machine is set to 80°C;

During the preparation process, the screw speed of the twin-screw extruder and the winding speed of the automatic winder are controlled to ensure that the weight fraction ratio of the continuous long glass fiber and the long carbon chain bio-based polyamide resin composition is 65:35, and continuous Long glass fiber reinforced long carbon chain bio-based polyamide unidirectional prepreg tape.

Preparation Example 4 Preparation of continuous long carbon fiber reinforced bio-based long carbon chain polyamide unidirectional prepreg tape:

The parts by weight of raw materials of the long carbon chain bio-based polyamide resin composition include the following components: long carbon chain bio-based polyamide: 94.5 parts, antioxidant 1098: 0.3 parts, antioxidant 168: 0.3 parts, internal lubricant WAXE: 0.2 parts, external lubricant WAXC: 0.2 parts, compatibilizer POE-g-MAH: 4 parts, coupling agent KH560: 0.5 parts. Adding the above components into a high-speed mixer and mixing to obtain a long carbon chain bio-based polyamide resin composition;

The screw speed is 400rpm; the aspect ratio of the twin-screw extruder is 1:36;

In the preparation process, the screw speed of the twin-screw extruder and the winding speed of the automatic winder are controlled to ensure that the weight fraction ratio of the continuous long carbon fiber and the long carbon chain bio-based polyamide resin composition is 65:35, and the continuous long carbon fiber is obtained. Carbon fiber reinforced long carbon chain bio-based polyamide unidirectional prepreg tape.

Example 1

Prepreg A: Continuous long glass fiber reinforced PA513 unidirectional prepreg, prepared as in Preparation Example 3, with a thickness of 0.28mm and a fiber content of 60.5wt%;

Prepreg tape B: continuous long glass fiber reinforced PA56 unidirectional prepreg tape, the preparation method is as in Preparation Example 1, the thickness is 0.32mm, and the fiber content is 61.3wt%;

Cut the prepreg tape to the size of the template, place a layer of release cloth or release paper on the upper and lower layers of the template, and place different layers of prepreg tape in the middle for compression molding, specifically:

The temperature of the molding machine is set at 260°C, and 6 layers of prepreg B are cross-laid at 0° and 90°, and a layer of prepreg A is laid on the top and bottom of the adjacent prepreg B at 90°. Control the pressure at 3MPa, preheat for 5 minutes, exhaust 3 times, hold the pressure for 8 minutes, then move to the cooling layer to cool at a cooling rate of 15°C/min, and prepare a continuous long fiber reinforced thermoplastic composite sheet A with a thickness of 2.31mm [6B]-A.

Example 2

The temperature of the molding machine is set at 260°C, 4 layers of prepreg B are cross-laid at 0° and 90°, and two layers of prepreg A are cross-laid at 0° and 90° on the upper and lower sides respectively, and the pressure of the molding machine is controlled at 3MPa. Preheat for 5 minutes, exhaust 3 times, hold pressure for 8 minutes, then move to the cooling layer and cool at a cooling rate of 15°C/min to prepare a continuous long fiber reinforced thermoplastic composite sheet 2A-[4B]-2A with a thickness of 2.28mm , the structure diagram is shown in Figure 1, 1 in Figure 1 represents 2A, A is continuous long glass fiber reinforced PA513 unidirectional prepreg tape, 2 in Figure 1 represents 4B, and B is continuous long glass fiber reinforced PA56 unidirectional prepreg bring.

Example 3

Prepreg A: Continuous long glass fiber reinforced PA510 unidirectional prepreg, prepared as in Preparation Example 3, with a thickness of 0.31mm and a fiber content of 62.8wt%;

The temperature of the molding machine is set at 260°C, 4 layers of prepreg B are cross-laid at 0° and 90°, and two layers of prepreg A are cross-laid at 0° and 90° on the upper and lower sides respectively, and the pressure of the molding machine is controlled at 3MPa. Preheat for 5 minutes, exhaust 3 times, hold pressure for 8 minutes, and then move to the cooling layer to cool at a cooling rate of 15°C/min to prepare a continuous long fiber reinforced thermoplastic composite sheet 2A-[4B]-2A with a thickness of 2.39mm .

Example 4

Prepreg A: Continuous long glass fiber reinforced PA512 unidirectional prepreg, prepared as in Preparation Example 3, with a thickness of 0.28mm and a fiber content of 62.1wt%;

The temperature of the molding machine is set to 260°C, 6 layers of prepreg B are cross-laid at 0° and 90°, and a layer of prepreg A is cross-laid at 90° relative to the adjacent prepreg B, and the pressure of the molding machine is Controlled at 3MPa, preheat for 5 minutes, exhaust 3 times, hold pressure for 8 minutes, then move to the cooling layer to cool at a cooling rate of 15°C/min, and prepare a continuous long fiber reinforced thermoplastic composite sheet A-[ 6B]-A, its structural diagram is shown in Figure 2, 3 in Figure 2 represents A, A is continuous long glass fiber reinforced PA512 unidirectional prepreg tape, 4 in Figure 2 represents 6B, and B is continuous long glass fiber reinforced PA56 Unidirectional prepreg tape.

Example 5

Prepreg A: Continuous long glass fiber reinforced PA515 unidirectional prepreg, prepared as in Preparation Example 3, with a thickness of 0.27mm and a fiber content of 62.8wt%;

The temperature of the molding machine is set at 260°C, and 6 layers of prepreg B are cross-laid at 0° and 90°, and a layer of prepreg A is laid on the top and bottom of the adjacent prepreg B at 90°. Control the pressure at 3MPa, preheat for 5 minutes, exhaust 3 times, hold the pressure for 8 minutes, then move to the cooling layer to cool at a cooling rate of 15°C/min, and prepare a continuous long fiber reinforced thermoplastic composite sheet A- with a thickness of 2.26mm [6B]-A.

Example 6

Prepreg tape A: continuous long carbon fiber reinforced PA513 unidirectional prepreg tape, the preparation method is as in preparation example 4, the thickness is 0.21mm, and the fiber content is 51.3wt%;

Prepreg tape B: continuous long carbon fiber reinforced PA56 unidirectional prepreg tape, the preparation method is as in preparation example 2, the thickness is 0.24mm, and the fiber content is 50.4wt%;

The temperature of the molding machine is set at 260°C, and 8 layers of prepreg B are cross-laid at 0° and 90°, and a layer of prepreg A is cross-laid at 90° with respect to the adjacent prepreg B, and the pressure of the molding machine is Controlled at 3MPa, preheat for 5 minutes, exhaust 3 times, hold pressure for 8 minutes, then move to the cooling layer and cool at a cooling rate of 15°C/min to prepare a continuous long fiber reinforced thermoplastic composite sheet A-[ 8B]-A.

Example 7

The temperature of the molding machine is set at 260°C, 6 layers of prepreg B are cross-laid at 0° and 90°, and two layers of prepreg A are cross-laid at 0° and 90° on the upper and lower sides respectively, and the pressure of the molding machine is controlled at 3MPa. Preheat for 5 minutes, exhaust 3 times, hold the pressure for 8 minutes, then move to the cooling layer and cool at a cooling rate of 15°C/min to prepare a continuous long fiber reinforced thermoplastic composite sheet 2A-[6B]-2A with a thickness of 2.25mm .

Example 8

Prepreg tape A: continuous long carbon fiber reinforced PA510 unidirectional prepreg tape, the preparation method is as in Preparation Example 4, the thickness is 0.23mm, and the fiber content is 50.1wt%;

Comparative example 1

Prepreg tape: continuous long glass fiber reinforced PA6 unidirectional prepreg tape, the process preparation method refers to Preparation Example 3 (only the raw material long carbon chain bio-based polyamide of the resin composition is replaced by PA6), the thickness is 0.31mm, the fiber content 61.8wt%;

Cut the prepreg tape to the size of the template, place a layer of release cloth or release paper on the upper and lower layers of the template, place the prepreg tape in the middle, and perform compression molding, specifically:

The temperature of the molding machine is set at 228°C, and 8 layers of the above-mentioned prepreg tapes are cross-laid at 0° and 90°. The pressure of the molding machine is controlled at 3MPa. First, preheat for 5 minutes, exhaust 3 times, hold the pressure for 8 minutes, and then move to the cooling layer Cool at a cooling rate of 15°C/min to prepare a continuous long fiber reinforced thermoplastic composite sheet with a thickness of 2.24mm.

Comparative example 2

Prepreg tape: continuous long carbon fiber reinforced PA6 unidirectional prepreg tape, the process preparation method refers to Preparation Example 4 (only the raw material long carbon chain bio-based polyamide of the resin composition is replaced by PA6), the thickness is 0.23mm, and the fiber content is 50.9 wt%;

The temperature of the molding machine is set at 228°C, and the above prepreg tapes are cross-laid at 0° and 90° for 10 layers. The pressure of the molding machine is controlled at 3MPa. First, preheat for 5 minutes, exhaust 3 times, hold the pressure for 8 minutes, and then move to the cooling layer Cool at a cooling rate of 15°C/min to prepare a continuous long fiber reinforced thermoplastic composite sheet with a thickness of 2.12mm.

Comparative example 3

Prepreg B: continuous long glass fiber reinforced PA6 unidirectional prepreg, the process preparation method refers to Preparation Example 3 (only the raw material long carbon chain bio-based polyamide of the resin composition is replaced by PA6), the thickness is 0.31mm, the fiber The content is 61.8wt%;

The temperature of the molding machine is set at 228°C, and 6 layers of prepreg B are cross-laid at 0° and 90°, and a layer of prepreg A is cross-laid at 90° with respect to the adjacent prepreg B, and the pressure of the molding machine is Controlled at 3MPa, preheated for 5 minutes, exhausted 3 times, held for 8 minutes, then moved to the cooling layer and cooled at a cooling rate of 15°C/min to prepare a continuous long fiber reinforced thermoplastic composite sheet 1A-[ 6B]-1A.

Comparative example 4

Prepreg tape B: continuous long carbon fiber reinforced PA6 unidirectional prepreg tape, the process preparation method refers to Preparation Example 4 (only the raw material long carbon chain bio-based polyamide of the resin composition is replaced by PA6), the thickness is 0.23mm, the fiber content is 50.9wt%;

The temperature of the molding machine is set at 228°C, and 8 layers of prepreg B are cross-laid at 0° and 90°, and a layer of prepreg A is cross-laid at 90° relative to the adjacent prepreg B respectively. Controlled at 3MPa, preheat for 5 minutes, exhaust 3 times, hold pressure for 8 minutes, then move to the cooling layer and cool at a cooling rate of 15°C/min to prepare a continuous long fiber reinforced thermoplastic composite sheet A-[ 8B]-A.

The samples prepared in Examples 1-8 and Comparative Examples 1-4 above were respectively subjected to bending test, HDT test and water absorption test. The test method is as follows, and the test results are shown in Table 1 below.

(1) Bending test (bending strength, bending modulus): According to the requirements of the ISO 14125 standard, cut out a sample with a sample size of 80 mm long, 10 mm wide, and 2 mm thick for the bending test.

(2) Heat deflection temperature (HDT) experiment: The test refers to the national standard GB/T 1634.2-2004. First, a specimen with a sample size of 120mm long, 10mm wide and 2mm thick is prepared, and the applied bending stress is 1.8Mpa for HDT. experiment.

(3) Water absorption test: The test refers to the standard ASTM-D570-2005, and a 60mm long, 60mm wide, and 2mm thick composite plate is prepared as a water absorbent plate. According to the test method of plastic water absorption, the test time is 24h.

(4) Tensile test (tensile strength, tensile modulus, Poisson's ratio): According to the requirements of ASTM D3039 standard, the sample size is 80mm long, 10mm wide, and 2mm thick.

The performance test result of the composite plate prepared by table 1 embodiment 1-8 and comparative example 1-4

It can be seen from Table 1 that:

By comparing the examples and comparative examples, it can be found that the strength and modulus of the continuous long glass fiber reinforced bio-based polyamide composite sheet are significantly improved compared with the corresponding performance of the continuous long glass fiber reinforced PA6 composite sheet, and the heat resistance is also significantly better. For continuous long glass fiber reinforced PA6 composite sheet, the water absorption performance is lower than that of continuous long glass fiber reinforced PA6 composite sheet;

By comparing the examples and comparative examples, it can be found that the strength and modulus of the continuous long carbon fiber reinforced bio-based polyamide composite sheet are significantly improved compared with the corresponding performance of the continuous long carbon fiber reinforced PA6 composite sheet, and the heat resistance is also significantly better than that of the continuous long carbon fiber reinforced PA6 composite sheet. Carbon fiber reinforced PA6 composite sheet has lower water absorption performance than continuous carbon fiber reinforced PA6 composite sheet.

Although the specific implementation of the present invention has been described above, those skilled in the art should understand that this is only an example, and the protection scope of the present invention is defined by the appended claims. Those skilled in the art can make various changes or modifications to these embodiments without departing from the principle and essence of the present invention, but these changes and modifications all fall within the protection scope of the present invention.

Claims

A continuous long fiber reinforced thermoplastic composite sheet, characterized in that it includes m layers of prepreg A and n layers of prepreg B, and the outer layer is the prepreg A; wherein, m≥2, n≥1 , and m and n are integers;

The prepreg tape A is a continuous long fiber reinforced long carbon chain polyamide resin unidirectional prepreg tape, which includes continuous long fibers and long carbon chain polyamide resin;

The prepreg tape B is a continuous long fiber reinforced short carbon chain polyamide resin unidirectional prepreg tape, which includes continuous long fiber and short carbon chain polyamide resin.
The continuous long fiber reinforced thermoplastic composite sheet according to claim 1, wherein the continuous long fiber reinforced thermoplastic composite sheet comprises m 1 A-[n 1 Bm 2 An 2 B]-m 3 A, wherein, m =m 1 +m 2 +m 3 , m 1 ≥1, m 2 ≥0, m 3 ≥1; n=n 1 +n 2 , n 1 ≥0, n 2 ≥0, and n 1 and n 2 are not 0 at the same time; m 1 , m 2 , m 3 , n 1 and n 2 are all integers.
The continuous long fiber reinforced thermoplastic composite sheet according to claim 1, wherein the sum of the values of m and n is 3-100;

And/or, said n is 1-98;

And/or, the prepregs A are each independently selected from the same or different continuous long fiber reinforced long carbon chain polyamide resin unidirectional prepregs; the prepregs B are each independently selected from the same or different Continuous long fiber reinforced short carbon chain polyamide resin unidirectional prepreg tape;

And/or, the thickness of the prepreg tape A is 0.15-0.5mm;

And/or, the thickness of the prepreg tape B is 0.15-0.5mm;

And/or, the total thickness of the continuous long fiber reinforced thermoplastic composite sheet is >0.5mm;

And/or, the layup mode between the layers in the continuous long fiber reinforced thermoplastic composite sheet is parallel layup or cross layup;

The crossing mode of the cross-laminated layer can be 0°-90° crossing, such as 45° crossing or 90° crossing;

And/or, the short carbon chain polyamide resin is a short carbon chain bio-based polyamide resin;

And/or, the long carbon chain polyamide resin is a long carbon chain bio-based polyamide resin;

And/or, in the prepreg tape A, the mass percentage of the continuous long fibers is 40-80%, preferably 60-70%, and the mass percentage means that the mass percentage of the continuous long fibers accounts for The quality of the prepreg tape A;

And/or, the mass percentage of the continuous long fibers in the prepreg B is 40-80%, preferably 60-70%, and the mass percentage means that the mass of the continuous long fibers accounts for all The quality of the above prepreg tape B;

And/or, the water content of the prepreg tape A is lower than 2000ppm, preferably lower than 1200ppm, such as 100-1200ppm;

And/or, the water content of the prepreg tape B is lower than 2000ppm, preferably lower than 1200ppm, such as 100-1200ppm.
The continuous long fiber reinforced thermoplastic composite sheet according to any one of claims 1-3, wherein the short carbon chain polyamide resin is PA56;

Among them, the PA56 preferably has the following characteristics: the relative viscosity is 1.9-2.7, the amino-terminal content is 42-60mmol/kg, and the melting point is 252-255°C; preferably, the bio-based content is 43%-46%;

And/or, the long carbon chain polyamide resin is selected from one or more of PA510, PA511, PA512, PA513, PA514, PA515, PA516, PA517 and PA518;

Among them, the long carbon chain polyamide resin preferably has the following characteristics: relative viscosity of 1.8-2.7; terminal amino content of 42-60 mmol/kg, melting point of 170°C-320°C; preferably, bio-based content of 29 %-100%;

And/or, the fiber type of the continuous long fiber includes carbon fiber, glass fiber, basalt fiber or aramid fiber.
The continuous long fiber reinforced thermoplastic composite sheet according to claim 4, wherein the continuous long fiber is a continuous long glass fiber, and the single filament diameter of the continuous long glass fiber can be 8-15 μm, preferably 8-10 μm; the linear density of the continuous long glass fiber can be 1000-3600Tex, preferably 1200Tex, 2400Tex;

Alternatively, the continuous long fibers are continuous long carbon fibers; the continuous long carbon fibers are preferably polyacrylonitrile carbon fibers; the number of monofilaments of the continuous long carbon fibers can be 20000-30000, preferably 12000 or 24000 pieces; the single filament diameter of the continuous long carbon fiber can be 5-10 μm, preferably 6-8 μm.
The continuous long fiber reinforced thermoplastic composite sheet according to claim 1, wherein the prepreg A includes continuous long glass fiber and long carbon chain polyamide resin, and the long carbon chain polyamide resin is PA510, PA511 , PA512, PA513, PA514, PA515 and PA516 in any one or more; preferably said prepreg tape A is continuous long glass fiber reinforced long carbon chain polyamide resin thermoplastic unidirectional prepreg tape; or, the Said prepreg tape A comprises continuous long carbon fiber and long carbon chain polyamide resin, and said long carbon chain polyamide resin is any one or more in PA510, PA511, PA512, PA513, PA514, PA515 and PA516; Preferably The prepreg tape A described above is a continuous long carbon fiber reinforced long carbon chain polyamide resin thermoplastic unidirectional prepreg tape;

And/or, the prepreg B includes continuous long glass fibers and PA56, preferably the prepreg B is a continuous long glass fiber reinforced PA56 unidirectional prepreg; or, the prepreg B includes continuous long carbon fiber and PA56, preferably the prepreg tape B is continuous long carbon fiber reinforced PA56 unidirectional prepreg tape.
The continuous long fiber reinforced thermoplastic composite sheet according to claim 6, wherein, in the continuous long fiber reinforced thermoplastic composite sheet, the prepreg A is a continuous long glass fiber reinforced long carbon chain polyamide resin thermoplastic sheet To the prepreg tape, the prepreg tape B is a continuous long glass fiber reinforced PA56 unidirectional prepreg tape;

Alternatively, in the continuous long fiber reinforced thermoplastic composite sheet, the prepreg tape A is a continuous long carbon fiber reinforced long carbon chain polyamide resin thermoplastic unidirectional prepreg tape, and the prepreg tape B is a continuous long carbon fiber reinforced PA56 unidirectional prepreg tape. to the prepreg tape.
A method for preparing a continuous long fiber reinforced thermoplastic composite sheet as claimed in any one of claims 1-7, characterized in that it comprises the following steps: carrying out the prepreg B with the prepreg A laying layers and compression molding to obtain the continuous long fiber reinforced thermoplastic composite board.
The preparation method according to claim 8, characterized in that, the way of laying layers is cross laying or parallel laying; wherein, the crossing way of said cross laying can be 0°-90° crossing, such as 45 °Cross, 90°Cross;

And/or, before the layer laying, it also includes the step of drying the prepreg tape; wherein,

Described drying can be vacuum drying;

The drying temperature is preferably 85-120°C;

The drying time is preferably 4-25h;

And/or, the equipment used in the molding is a molding machine, and the molding machine can be a double steel belt molding compound machine;

And/or, the molding temperature is 5-10°C higher than the melting point of the short carbon chain polyamide resin, preferably 190-310°C;

And/or, the compression molding pressure is 1-5MPa;

And/or, the compression molding method is continuous compression molding or direct compression molding;

Wherein, when the compression molding method is continuous compression molding, it preferably includes the step of continuous automatic layer laying;

Wherein, when the compression molding method is direct compression molding, the direct compression molding preferably includes the steps of preheating, exhausting, pressure maintaining and/or cooling;

The preheating time is preferably 3-8min;

The number of times of the exhaust is preferably 3-6 times;

The time of said holding pressure is preferably 5-10min;

The temperature drop rate of the cooling is preferably 5-20°C/min;

The temperature after the cooling is preferably in the range of 20±5°C;

And/or, the prepreg tape A and the prepreg tape B are prepared by a melt impregnation method; preferably, the melt impregnation method includes the following steps:

S1. Extrude the polyamide resin composition, and make the extruded melt enter the dipping die; wherein, the polyamide resin composition includes the long carbon chain polyamide resin or the short carbon chain polyamide resin;

S2. Leading the continuous long fibers into the impregnation die to impregnate the melt and the continuous long fibers;

S3. Molding, cooling, drawing and winding the impregnated continuous long fibers to obtain the prepreg A or the prepreg B;

Wherein, preferably, the polyamide resin composition also includes additives;

Described additive preferably comprises one or more in antioxidant, lubricant, compatibilizer and coupling agent;

More preferably, the polyamide resin composition includes the following components in parts by weight: 81.8-99.8 parts of the long carbon chain polyamide resin or the short carbon chain polyamide resin, 0.2-1.6 parts of antioxidant, 0-0.8 parts of lubricant, 0-15 parts of compatibilizer and 0-0.8 parts of coupling agent;

Wherein, the antioxidant is preferably selected from one or more of antioxidant 168, antioxidant 1098, antioxidant 1010 and antioxidant S9228;

Wherein, the lubricant preferably includes an external lubricant such as WAXC and an internal lubricant such as WAXE;

Wherein, the compatibilizer can be selected from one or more of PP-g-MAH, POE-g-MAH, POE-g-GMA and EPDM-g-MAH;

Wherein, the coupling agent can be selected from one or more of coupling agent KH550, coupling agent KH560 or coupling agent KH570.
A use of the aforementioned continuous long fiber reinforced thermoplastic composite sheet in plastic products; wherein, the plastic products preferably include plastic products in auto parts.