CN112009054A

CN112009054A - Composite sheet and preparation method and application thereof

Info

Publication number: CN112009054A
Application number: CN201910454111.2A
Authority: CN
Inventors: 黄汉进; 彭树文
Original assignee: Honeywell Performance Materials and Technologies China Co Ltd
Current assignee: Honeywell Performance Materials and Technologies China Co Ltd
Priority date: 2019-05-28
Filing date: 2019-05-28
Publication date: 2020-12-01

Abstract

The invention relates to a composite sheet and a preparation method thereof. The composite sheet is a hot-pressed part of one or more layers of composite yarn fabrics, the composite yarn comprises multi-component fibers and high-strength fibers, wherein the multi-component fibers are selected from three-layer composite fibers with polypropylene as a core layer, ethylene copolymer as a sheath layer, polypropylene as a core layer, ethylene copolymer as a middle layer and polyethylene as a sheath layer, and the high-strength fibers are selected from ultrahigh molecular weight polyethylene fibers, glass fibers, carbon fibers, aramid fibers and basalt fibers. The composite sheet material of the invention utilizes the multicomponent fiber with better hot processing performance to overcome the problem that some high-strength fibers have low viscosity and/or poor heat resistance and can not be thermoformed, thereby expanding the application field of the high-strength fibers.

Description

Composite sheet and preparation method and application thereof

Technical Field

The invention belongs to the field of fiber composite materials. Specifically, the invention relates to a composite sheet and a preparation method and application thereof.

Background

The ultra-high molecular weight polyethylene fiber (UHMWPE) has the excellent performances of low density, high strength, high modulus and the like.

As a high-performance fiber, the ultrahigh molecular weight polyethylene fiber has low elongation at break, and has good fatigue resistance and friction resistance.

Because the molecular structure of the polyethylene does not contain amino, hydroxyl and other groups with good activity, and the crystallinity of the molecules is high, the polyethylene fiber has stable performance in water or other corrosive media, has small density, light weight and good energy absorption, and is suitable for being used as a light reinforcing material in thermoplastic plastics.

CN108864664A discloses a long fiber reinforced thermoplastic composite material, wherein the reinforcing fibers used are ultra-high molecular weight polyethylene fibers.

CN108529936A discloses an ultra-high molecular weight polyethylene fiber reinforced polymer matrix composite material and a preparation method thereof.

Glass fiber, carbon fiber, aramid fiber, basalt fiber and the like also belong to high-strength fibers, and are often used as reinforcing fibers for reinforcing resins.

CN109206855A discloses a preparation method of a resin-based fiber reinforced composite material, wherein the used reinforcing fiber is selected from glass fiber, carbon fiber, aramid fiber and basalt fiber.

However, ultra-high molecular weight polyethylene fibers, glass fibers, carbon fibers, aramid fibers, and basalt fibers have poor adhesion and/or heat resistance and thus cannot be thermoformed, which limits their application as lightweight, impact-resistant reinforcements for many thermoformed plastic articles.

It is therefore desirable to compensate for the lack of thermoformability of certain high strength fibers that have poor adhesion and/or heat resistance and are therefore not amenable to high strength articles.

Disclosure of Invention

It is an object of the present invention to remedy certain deficiencies in high strength fibers that are not thermoformable due to poor adhesion and/or heat resistance, thereby providing a composite material that can be used to make high strength articles.

According to a first aspect of the present invention there is provided a composite sheet which is a hot press of one or more layers of a composite yarn fabric, the composite yarn comprising multicomponent fibres selected from sheath-core composite fibres having polypropylene as the core layer, ethylene or propylene copolymers as the sheath layer and triple layer composite fibres having polypropylene as the core layer, ethylene or propylene copolymers as the intermediate layer and polyethylene as the sheath layer, and high strength fibres selected from ultra high molecular weight polyethylene fibres, glass fibres, carbon fibres, aramid fibres and basalt fibres.

According to a second aspect of the present invention there is provided a method of making a composite sheet according to the first aspect of the present invention comprising the steps of:

i) providing a composite yarn comprising the multicomponent fibers and the high strength fibers;

ii) forming the composite yarn into a fabric; and

iii) hot pressing one or more layers of said fabric and then cooling to obtain a composite sheet.

According to a third aspect of the present invention, there is provided a composite sheet which is a laminate of at least two layers of multicomponent fiber fabrics and at least one layer of high-strength fiber fabric, wherein the multicomponent fiber fabric is selected from the group consisting of a sheath-core composite fiber in which polypropylene is used as a core layer, an ethylene copolymer or a propylene copolymer is used as a sheath layer, and a trilayer composite fiber in which polypropylene is used as a core layer, an ethylene copolymer or a propylene copolymer is used as a middle layer, and polyethylene is used as a sheath layer, and the high-strength fiber is selected from the group consisting of an ultrahigh-molecular-weight polyethylene fiber, a glass fiber, a carbon fiber, an aramid fiber, and a basalt fiber.

According to a fourth aspect of the present invention there is provided a method of making a composite sheet according to the third aspect of the present invention, comprising:

i) providing the multicomponent fiber fabric and the high strength fiber fabric;

ii) laying up at least two layers of a multicomponent fiber fabric and at least one layer of a high strength fiber fabric, wherein the lowest layer and the highest layer are both the multicomponent fiber fabric; and

iii) hot pressing the product obtained in the step ii), and then cooling to obtain the composite sheet.

According to a fifth aspect of the present invention, there is provided an article prepared using the above composite sheet.

The composite sheet material of the invention utilizes the multi-component fiber with better hot processing performance to overcome the problem that some high-strength fibers cannot be thermoformed due to poor bonding property and/or heat resistance, expands the application field of the high-strength fibers, and is used for preparing composite material products which are light in weight, high in strength and capable of being thermoformed with high efficiency.

Drawings

The invention will be illustrated hereinafter with reference to the accompanying drawings, in which:

FIG. 1 shows a schematic of a process route for making a composite sheet according to one aspect of the present invention.

FIG. 2 shows a schematic of a process route for making a composite sheet according to another aspect of the present invention.

Detailed description of the preferred embodiments

Various aspects of the invention and still further objects, features and advantages will be more fully apparent hereinafter.

According to a first aspect of the present invention there is provided a composite sheet which is a hot-pressed article of one or more layers of a composite yarn fabric, the composite yarn comprising multicomponent fibres selected from the group consisting of polypropylene as a core layer, sheath-core composite fibres with ethylene copolymer as a sheath layer and triple layer composite fibres with polypropylene as a core layer, ethylene copolymer as an intermediate layer and polyethylene as a sheath layer, and high strength fibres selected from the group consisting of ultra high molecular weight polyethylene fibres, glass fibres, carbon fibres, aramid fibres and basalt fibres.

In a preferred embodiment, in the composite yarn, the multicomponent fibers act as sheath yarns and the high strength fibers act as core yarns.

Preferably, the polypropylene has a Melt Flow Index (MFI) of 0.2 to 60g/10min, more preferably 20 to 40g/10min, measured at 230 ℃ with a 2.16Kg weight, such as Z30S from China petrochemical Co., Ltd, with an MFI of 25g/10 min.

The use of polypropylene as the core layer can provide a composite fiber stiffness modulus and flexural modulus.

Preferably, the ethylene copolymer is a copolymer of ethylene as a first monomer and a second monomer selected from the group consisting of propylene, butene, hexene and octene.

In some embodiments, the ethylene copolymer is a copolymer of ethylene as a first monomer and a second monomer selected from the group consisting of propylene, butene, hexene, and octene, wherein the second monomer is present in an amount of 0.1 mole% to 40 mole%, preferably 8 mole% to 35 mole%, such as Engage 8401 and 8450 resins from Dow.

In some embodiments, the ethylene copolymer is a copolymer of ethylene and propylene wherein the ethylene content is from 0.1 mole% to 30 mole%, preferably from 8 mole% to 25 mole%, such as Versify 4000 resin from Dow corporation.

In some embodiments, the ethylene copolymer is a block copolymer comprising 20 mole% to 80 mole% ethylene blocks and 80 mole% to 20 mole% random ethylene octene or random ethylene butene blocks, preferably a block copolymer comprising 30 mole% to 70 mole% ethylene blocks and 70 mole% to 30 mole% random ethylene octene or random ethylene butene blocks, such as the infusi 9817 resin from Dow corporation.

In some embodiments, the ethylene copolymer is a block copolymer comprising 20 mole percent to 80 mole percent propylene blocks and 80 mole percent to 20 mole percent random ethylene propylene or ethylene butene or ethylene octene blocks, preferably a block copolymer comprising 30 mole percent to 70 mole percent propylene blocks and 70 mole percent to 30 mole percent random ethylene propylene or ethylene butene or ethylene octene blocks, such as INTUNE D5545 resin from DOW.

Preferably, the polyethylene has a Melt Flow Index (MFI) of 0.2 to 20g/10min, preferably 1 to 10g/min, more preferably 1 to 6g/min, measured at 190 ℃ with a 2.16Kg weight, such as Low Density Polyethylene (LDPE), Linear Low Density Polyethylene (LLDPE) and High Density Polyethylene (HDPE), such as T55 to 300M HDPE resin from Mitsu petrochemical Co., Ltd, with an MFI of 2g/10 min.

The use of polyethylene or ethylene copolymers as the sheath provides thermal bonding of the composite fiber.

Preferably, in the sheath-core composite fiber, the volume ratio of the sheath layer to the core layer is between 1: 1 and 1: 10, preferably between 1: 1 and 1: 2.5.

Preferably, in the three-layer composite fiber, the volume ratio of the core layer/the middle layer/the skin layer is 80% -50%/10% -25%/10-25%.

Preferably, the total denier of the multicomponent fiber is 100-. Preferably, the multicomponent fibers have a tensile strength of not less than 1.5g/dtex, preferably not less than 2.5 g/dtex.

In some embodiments, the multicomponent fiber has a total denier of 200-3200 denier and a tensile strength of 2.5 to 6.0 g/dtex.

The high-strength fibers are selected from ultra-high molecular weight polyethylene fibers, glass fibers, carbon fibers, aramid fibers and basalt fibers, and can be obtained from the market or prepared by the market.

Preferably, the total denier of the high strength fibers is 200-1600 denier. Preferably, the high strength fibers have a tensile strength of not less than 5g/dtex, more preferably not less than 10 g/dtex.

In some embodiments, the high strength fibers have a total denier of 200-1600 denier and a tensile strength of 10-40 g/dtex.

Preferably, the weight ratio of multicomponent fibers to high strength fibers in the composite yarn is in the range of 100: 1 to 100: 100.

Preferably, the gram weight of the composite yarn fabric is 100g/m²-500g/m²Preferably 150-300g/m²。

In some embodiments, the fabric is a warp and weft fabric.

Preferably, in the composite sheet, the number of layers of the fabric is 1 to 10.

When the number of layers of the fabric is greater than 1, the layers of the multicomponent fiber fabric may be the same or different.

ii) forming the composite yarn into a fabric; and

Figure 1 shows a schematic diagram of a process route for making a composite sheet according to an embodiment of the second aspect of the present invention. It is to be understood that this figure is merely illustrative and not intended to limit the method of the present invention.

In some embodiments, step i) comprises providing the multicomponent fibers and the high strength fibers.

The multicomponent fibers can be prepared using composite spinning techniques known in the art.

For example, two screw extruders can be used, the sheath material and the core material are respectively placed in different screws, extruded at a temperature above the melting point of each material, combined into a neck mold after passing through a layer body distributor, and stretched and cooled to obtain the sheath-core composite fiber.

For example, three screw extruders can be used, the skin layer material, the middle layer material and the core layer material are respectively placed in different screws, extruded at a temperature above the melting point of each material, merged into a neck mold after passing through a layer distributor, stretched and cooled to obtain the three-layer composite fiber.

The high strength fibers may be made on their own or commercially available.

The composite yarns and fabrics of composite yarns may be prepared by methods known in the art. The composite yarn may be obtained, for example, by blending.

The hot pressing may be carried out on any suitable equipment.

Preferably, the hot pressing is performed in a mold or on a press.

Preferably, the hot pressing is carried out at a temperature in the range of 90-160 ℃, preferably in the range of 110-150 ℃, at a pressure in the range of 0.1-100MPa, preferably in the range of 0.5-20MPa, for a period of 20 seconds to 0.5 hours, preferably 1 minute to 15 minutes, more preferably 2 minutes to 6 minutes.

In some embodiments, the cooling is performed by allowing the finished product to cool naturally to ambient temperature.

In some embodiments, the cooling is performed by directly cooling the finished product with cold air or water.

In some embodiments, the cooling is performed by cooling the mold.

Preferably, the cooling is performed by cooling the mold with a cooling medium, such as cold air or water.

The laminate may be a hot-pressed laminate.

Preferably, the polyethylene has a Melt Flow Index (MFI) of 0.2 to 20g/10min, preferably 1 to 10g/10min, more preferably 1 to 6g/min, measured at 190 ℃ with a 2.16Kg weight, such as Low Density Polyethylene (LDPE), Linear Low Density Polyethylene (LLDPE) and High Density Polyethylene (HDPE), such as T55 to 300M HDPE resin from Mitsu petrochemical Co., Ltd, having an MFI of 2g/10 min.

Preferably, the grammage of the multicomponent fiber fabric is 100g/m²-500g/m²Preferably 150g/m²-300g/m²。

In some embodiments, the multicomponent fiber fabric is a warp and weft fabric having a grammage of 150-²Preferably, the warp and weft cloth is a single-layer twill warp cloth, and the yarn number proportion of the warp direction and the weft direction is basically the same and is uniformly distributed.

Preferably, the total denier of the high strength fibers is 200-1600 denier. Preferably, the high strength fibers have a tensile strength of not less than 5g/dtex, preferably not less than 10 g/dtex.

Preferably, the grammage of the high-strength fiber fabric is 100-200g/m²The fabric is single-layer warp and weft cloth or unidirectional UD cloth.

Preferably, the weight ratio of the multicomponent fiber fabric to the high strength fiber fabric in the composite sheet is in the range of 100: 1 to 100: 100.

Preferably, the number of layers of the multicomponent fiber fabric is 2 to 10.

Optionally, the layers of the multicomponent fiber fabric may be the same or different.

Preferably, the number of layers of the high-strength fiber fabric is 1-5.

When the number of the layers of the high-strength fiber fabric is more than 1, the high-strength fiber fabrics of the layers can be the same or different.

When the number of layers of the high-strength fiber fabric exceeds one layer, it is preferable that a multicomponent fiber fabric is spaced therein.

Figure 2 shows a schematic process route for making a composite sheet according to an embodiment of the fourth aspect of the present invention. It is to be understood that this figure is merely illustrative and not intended to limit the method of the present invention.

The high strength fibers may be made on their own or commercially available.

The fabric may be prepared by methods known in the art.

The hot pressing may be carried out on suitable equipment, for example in a hot press mould or on a press.

Preferably, the hot pressing is performed in a mould.

In some embodiments, the cooling is performed by cooling the mold.

The product prepared by the composite sheet material has the characteristics of light weight, high strength and impact resistance.

As examples of the article, mention may be made of light luggage, automobile impact-resistant parts (such as bumpers and the like), sports and leisure articles, safety protection articles such as helmets and the like.

The terms "comprising" and "including" as used herein encompass the case where other elements not explicitly mentioned are also included or included and the case where they consist of the mentioned elements.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. In the event that a definition of a term in this specification conflicts with a meaning commonly understood by those skilled in the art to which the invention pertains, the definition set forth herein shall govern.

Unless otherwise indicated, all numbers expressing quantities of ingredients, reaction conditions, and so forth used in the specification and claims are to be understood as being modified by the term "about". Accordingly, unless indicated to the contrary, the numerical parameters set forth herein are approximations that can vary depending upon the desired properties to be obtained.

Examples

The concept and technical effects of the present invention will be further described with reference to the following examples so that those skilled in the art can fully understand the objects, features and effects of the present invention. It should be understood that the examples are illustrative only and are not intended to limit the scope of the present invention.

Example 1

The sheath-core composite fiber is prepared by a composite spinning technology by using polypropylene (Z30S from China petrochemical Co., Ltd., MFI of 25g/10min) and ethylene copolymer (Engage 8401 resin from Dow corporation), wherein the polypropylene is used as a core layer material, and the ethylene copolymer is used as a sheath layer material. The spinning process used was as follows:

core layer screw extrusion temperature: 200 ℃ to 290 ℃ (increasing gradually from the feed section to the melt pump section);

skin layer screw extrusion temperature: 180 ℃ to 250 ℃ (increasing gradually from the feed section to the melt pump section);

spinneret temperature: 260 ℃;

number of spinneret holes: 96, pore diameter: 0.2 mm;

screw L/D ratio: 28;

stretching speed: 2000 m/min;

pump supply: 90 g/min;

the weight ratio of the sheath to the core is as follows: 4/6, respectively;

temperature of quenching air: 25 ℃;

the obtained multifilament fiber had a total fineness of 400 denier and a tensile strength of 2.8 g/dtex.

The obtained multifilament fiber and an ultra-high molecular weight polyethylene fiber (Spectra from Honeywell, total fiber fineness of 400 denier, tensile strength of 30g/dtex) were blended in a weight ratio of 100: 20 to form a composite yarn (5 bundles of 400 denier multifilament fiber and 1 bundle of 400 denier Spectra were respectively laid out, plied and twisted to 2400 denier composite yarn using a yarn plying machine), and the composite yarn was woven to have a grammage of 250g/m²The warp and weft fabrics of (1).

And (3) paving 4 layers of the warp and weft fabrics in a hot-pressing mold, laminating for 3 minutes at the temperature of 120 ℃ and under the pressure of 10MPa, then releasing the mold, and cooling the material at room temperature to obtain the thermoplastic plate.

Example 2

The sheath-core composite fiber is prepared by adopting polypropylene (Z30S from China petrochemical company Limited, the MFI of the fiber is 25g/10min) and ethylene copolymer (Versify 4000 resin from Dow company) through a composite spinning technology, wherein the polypropylene is used as a core layer material, and the ethylene copolymer is used as a skin layer material. The spinning process used was as follows:

spinneret temperature: 260 ℃;

number of spinneret holes: 96, pore diameter: 0.2 mm;

screw L/D ratio: 28;

stretching speed: 2000 m/min;

pump supply: 90 g/min;

the weight ratio of the sheath to the core is as follows: 4/6, respectively;

temperature of quenching air: 25 ℃;

the total fineness of the obtained multifilament fiber was 400 denier and the tensile strength was 2.9 g/dtex.

The obtained multifilament fiber and glass fiber (from glass fiber Y3, Tex, of Mount Taishan, China, with a yarn density of 45tex and a tensile strength of 15g/dtex) were mixed in a ratio of 100: 20 (5 bundles of 400 denier multifilament fibers and 1 bundle of Y3 glass fibers are respectively laid by a yarn plying machine, plied and twisted to 2400 denier) and then the composite yarn is knitted to have a gram weight of 250g/m²The warp and weft fabrics of (1).

And (3) paving 4 layers of the warp and weft fabrics in a hot-pressing mold, laminating for 5 minutes at the temperature of 150 ℃ and under the pressure of 20MPa, then releasing the mold, and cooling the material at room temperature to obtain the thermoplastic plate.

Example 3

The sheath-core composite fiber is prepared by a composite spinning technology by using polypropylene (Z30S from China petrochemical Co., Ltd., MFI of 25g/10min) and ethylene copolymer (INFUSE 9817 resin from Dow corporation), wherein the polypropylene is used as a core layer material, and the ethylene copolymer is used as a sheath layer material. The spinning process used was as follows:

spinneret temperature: 260 ℃;

number of spinneret holes: 96, pore diameter: 0.2 mm;

screw L/D ratio: 28;

stretching speed: 2000 m/min;

pump supply: 90 g/min;

the weight ratio of the sheath to the core is as follows: 4/6, respectively;

temperature of quenching air: 25 ℃;

the total fineness of the obtained multifilament fiber was 400 denier and the tensile strength was 3 g/dtex.

The obtained multifilament fiber and carbon fiber (GQ 3522 from Guanwei composite material, yarn density 66tex, tensile strength 20g/dtex) were blended at a weight ratio of 100: 20 to obtain a composite yarn (6 bundles of 400 denier multifilament fiber and 1 bundle of 66tex glass fiber were each laid out by a yarn plying machine, plied and twisted to 3000 denier), and the composite yarn was woven to have a grammage of 250g/m²The warp and weft fabrics of (1).

Example 4

The sheath-core composite fiber is prepared by a composite spinning technology by using polypropylene (Z30S from China petrochemical Co., Ltd., MFI of 25g/10min) and ethylene copolymer (INTUNE D5545 resin from Dow corporation), wherein the polypropylene is used as a core layer material, and the ethylene copolymer is used as a skin layer material. The spinning process used was as follows:

spinneret temperature: 260 ℃;

number of spinneret holes: 96, pore diameter: 0.2 mm;

screw L/D ratio: 28;

stretching speed: 2000 m/min;

pump supply: 90 g/min;

the weight ratio of the sheath to the core is as follows: 4/6, respectively;

temperature of quenching air: 25 ℃;

the obtained multifilament fiber had a total fineness of 400 denier and a tensile strength of 3.5 g/dtex.

The obtained multifilament fiber was blended with aramid fiber (Kevlar from DuPont, total fiber fineness of 400 denier, tensile strength of 27g/dtex) at a weight ratio of 100: 20 to obtain a multifilament yarn, and the multifilament yarn was woven to have a grammage of 250g/m²The warp and weft fabrics of (1).

Example 5

The three-layer composite fiber is prepared from polypropylene (Z30S from China petrochemical company Limited, with MFI of 25g/10min), ethylene copolymer (Versify 4000 resin from Dow company) and polyethylene (T55-300 HDPE resin from Zhongshatianjin petrochemical company Limited, with MFI of 2g/10min) by composite spinning technology, wherein the polypropylene is used as a core layer material, the ethylene copolymer is used as a middle layer material, and the polyethylene is used as a skin layer material. The spinning process used was as follows:

screw extrusion temperature of the middle layer: 180 ℃ to 250 ℃ (increasing gradually from the feed section to the melt pump section);

skin layer screw extrusion temperature: 190 ℃ and 280 ℃ (gradually increasing from the feeding section to the melt pump section);

spinneret temperature: 260 ℃;

number of spinneret holes: 96, pore diameter: 0.2 mm;

screw L/D ratio: 28;

stretching speed: 2000 m/min;

pump supply: 90 g/min;

skin layer/intermediate layer/core layer weight ratio: 2/2/6, respectively;

temperature of quenching air: 25 ℃;

the obtained multifilament fiber had a total fineness of 400 denier and a tensile strength of 3.2 g/dtex.

Example 6

spinneret temperature: 260 ℃;

number of spinneret holes: 96, pore diameter: 0.2 mm;

screw L/D ratio: 28;

stretching speed: 2000 m/min;

pump supply: 90 g/min;

the weight ratio of the sheath to the core is as follows: 4/6, respectively;

temperature of quenching air: 25 ℃;

Weaving the obtained sheath-core fiber into a weight of 250g/m²The warp and weft fabrics of (1). In a hot-pressing mould, 3 layers of sheath-core fiber warp-weft cloth and 2 layers of fabrics with the gram weight of 125g/m²The ultra-high molecular weight polyethylene fiber warp and weft cloth (the warp and weft cloth woven by Honeywell Spectra with the total fineness of 400 deniers and the tensile strength of 30g/dtex) is subjected to multilayer laying, wherein each 1 layer of ultra-high molecular weight polyethylene fiber warp and weft cloth is clamped between two adjacent 2 layers of sheath-core fiber warp and weft cloth, the layers are laminated for 3 minutes at the temperature of 120 ℃ and the pressure of 10MPa, and then a mould is filled with cold water to be cooled to room temperature to obtain the thermoplastic plate.

Example 7

The three-layer composite fiber obtained in example 5 was woven to have a grammage of 250g/m²The warp and weft fabrics of (1). 3 layers of composite fiber warp and weft cloth and 2 layers of composite fiber warp and weft cloth with the gram weight of 125g/m are arranged in a hot-pressing die²The ultra-high molecular weight polyethylene fiber warp and weft cloth (the warp and weft cloth woven by Honeywell Spectra with the total fineness of 400 deniers and the tensile strength of 30g/dtex) is subjected to multilayer laying, wherein each 1 layer of ultra-high molecular weight polyethylene fiber warp and weft cloth is clamped between two adjacent layers of composite fiber warp and weft cloth, the layers are laminated for 3 minutes at the temperature of 120 ℃ and the pressure of 10MPa, and then a mould is filled with cold water to be cooled to room temperature to obtain the thermoplastic plate.

Example 8 (comparative)

400 denier sheath-core fibers from example 1 were spun directly to 250g/m²The warp and weft fabrics of (1). And (3) hot-pressing the 4 layers of warp and weft fabrics on a flat vulcanizing machine, laminating for 3 minutes at the temperature of 140 ℃ and under the pressure of 10MPa, and then introducing cold water into a mold to cool to room temperature to obtain the thermoplastic plate.

Example 9

The thermoplastic sheets prepared in examples 1-8 were tested for mechanical properties and the results are summarized in table 1 below.

TABLE 1 mechanical Properties of thermoplastic sheets prepared in examples 1-8

Examples	Flexural modulus (MPa)	Tensile strength (Mpa)	Drop hammer impact (J)
				Test method	ASTM D747	ASTM D638	GB/T 14153-1993
1	1691	124	210
				2	2540	110	75
3	2915	130	71
				4	950	88	117
5	1805	132	201
				6	1140	101	151
7	1335	109	178
				8	1510	78	94

As can be seen from the results in table 1, the sheets prepared using inorganic high-strength fibers such as carbon fibers, glass fibers, etc. have significantly improved flexural modulus; the sheet prepared from aramid fibers has improved impact resistance and tensile strength. The sheet prepared by the ultra-high molecular weight polyethylene fiber has the advantages of obviously improving the impact property, the tensile strength and the bending rigidity.

Although a few aspects of the present invention have been shown and discussed, it would be appreciated by those skilled in the art that changes may be made in this aspect without departing from the principles and spirit of the invention, the scope of which is therefore defined in the claims and their equivalents.

Claims

1. A composite sheet material which is a heat-pressed article of one or more layers of a fabric of composite yarns comprising multicomponent fibers selected from the group consisting of core layer of polypropylene, core-sheath composite fibers of ethylene copolymer as a sheath layer, and triple layer composite fibers of polypropylene, intermediate layer of ethylene copolymer, and sheath layer of polyethylene, and high strength fibers selected from the group consisting of ultrahigh molecular weight polyethylene fibers, glass fibers, carbon fibers, aramid fibers, and basalt fibers.

2. Composite sheet according to claim 1, wherein the polypropylene has a Melt Flow Index (MFI) of 0.2-60g/10min, preferably 20-40g/10min, measured with a 2.16Kg weight at 230 ℃.

3. Composite sheet according to claim 1 or 2, characterized in that the ethylene copolymer is selected from:

i) a copolymer of ethylene as a first monomer and a second monomer selected from the group consisting of propylene, butene, hexene and octene, preferably wherein the content of the second monomer is 0.1 mol% to 40 mol%;

ii) a copolymer of ethylene and propylene, wherein the content of ethylene is from 0.1 mol% to 30 mol%;

iii) a block copolymer comprising 20 mole% to 80 mole% of an ethylene block and 80 mole% to 20 mole% of a random ethylene octene or random ethylene butene block; and

iv) block copolymers comprising from 20 mol% to 80 mol% of propylene blocks and from 80 mol% to 20 mol% of random ethylene propylene or ethylene butene or ethylene octene blocks.

4. Composite sheet according to any of claims 1 to 3, wherein the polyethylene has a Melt Flow Index (MFI) of 0.2 to 20g/10min, preferably 1 to 10g/min, more preferably 1 to 6g/min, measured with a 2.16Kg weight at 190 ℃.

5. The composite sheet according to any one of claims 1 to 4, wherein in the sheath-core composite fiber, the volume ratio of the sheath layer to the core layer is between 1: 1 and 1: 10, preferably between 1: 1 and 1: 2.5; in the three-layer composite fiber, the volume ratio of the core layer/the middle layer/the skin layer is 80-50%/10-25%.

6. The composite sheet according to any one of claims 1 to 5, wherein the multi-component fiber has a total titer of 100-; preferably, the total titer of the high-strength fiber is 200-1600 denier, and the tensile strength is not lower than 5g/dtex, preferably not lower than 10 g/dtex.

7. The composite sheet of any of claims 1-6, wherein the weight ratio of multicomponent fibers to high strength fibers in the composite yarn is in the range of 100: 1 to 100: 100; preferably, the gram weight of the composite yarn fabric is 100g/m²-500g/m²。

8. The composite sheet according to any of claims 1 to 7, wherein the number of layers of the fabric in the composite sheet is 1 to 10.

9. A method of making the composite sheet of any one of claims 1-8, comprising the steps of:

i) providing a composite yarn comprising the multicomponent fibers and high strength fibers;

ii) forming the composite yarn into a fabric; and

10. The method according to claim 9, characterized in that the hot pressing is carried out at a temperature in the range of 100-160 ℃, preferably in the range of 110-150 ℃ and at a pressure in the range of 0.1-100MPa, preferably in the range of 0.5-20MPa for 20 seconds to 0.5 hours, preferably 1 minute to 15 minutes, more preferably 2 minutes to 6 minutes.

11. A composite sheet material which is a laminate of at least two layers of multicomponent fiber fabrics and at least one layer of high-strength fiber fabric, wherein the multicomponent fiber fabric is arranged on the bottom layer and the top layer, the multicomponent fiber is selected from sheath-core composite fiber with polypropylene as a core layer, ethylene copolymer or propylene copolymer as a skin layer and three-layer composite fiber with polypropylene as a core layer, ethylene copolymer or propylene copolymer as an intermediate layer and polyethylene as a skin layer, and the high-strength fiber is selected from ultrahigh molecular weight polyethylene fiber, glass fiber, carbon fiber, aramid fiber and basalt fiber.

12. The composite sheet according to claim 11, wherein the polypropylene has a Melt Flow Index (MFI) of 0.2 to 60g/10min, more preferably 20 to 40g/10min, measured with a 2.16Kg weight at 230 ℃.

13. Composite sheet according to claim 11 or 12, characterized in that the ethylene copolymer is selected from:

iii) a block copolymer comprising 20 to 80 mole percent ethylene blocks and 80 to 20 mole percent random ethylene octene or random ethylene butene blocks; and

14. The composite sheet according to any of claims 11 to 13, wherein the polyethylene has a Melt Flow Index (MFI) of 0.2 to 20g/10min, preferably 1 to 10g/10min, more preferably 1 to 6g/min, measured with a 2.16Kg weight at 190 ℃.

15. The composite sheet according to any of claims 11 to 14, wherein in the sheath-core composite fiber, the volume ratio of the sheath layer to the core layer is between 1: 1 and 1: 10, preferably between 1: 1 and 1: 2.5; in the three-layer composite fiber, the volume ratio of the core layer/the middle layer/the skin layer is 80-50%/10-25%.

16. The composite sheet according to any of claims 11 to 15, wherein the multi-component fiber has a total titer of 100-; preferably, the total titer of the high-strength fibers is 200-1600 denier, and the tensile strength is not lower than 5g/dtex, more preferably not lower than 10 g/dtex.

17. The composite sheet according to any of claims 11 to 16, wherein the multicomponent fiber fabric has a grammage of 100-²Preferably 150-300g/m²(ii) a Preferably, the grammage of the high-strength fiber fabric is 100-200g/m²(ii) a Preferably, the weight ratio of the multicomponent fiber fabric to the high strength fiber fabric is in the range of 100: 1 to 100: 100.

18. The composite sheet according to any of claims 11 to 17, wherein the number of layers of the multicomponent fiber fabric is from 2 to 10; preferably, the number of layers of the high-strength fiber fabric is 1-5.

19. A method of making the composite sheet of any one of claims 11-18, comprising:

20. The method according to claim 19, characterized in that the hot pressing is performed at a temperature in the range of 100-160 ℃, preferably in the range of 110-150 ℃ at a pressure in the range of 0.1-100MPa, preferably in the range of 0.5-20MPa, for 20 seconds to 0.5 hours, preferably for 1 minute to 15 minutes, more preferably for 2 minutes to 6 minutes.

21. An article made with the composite sheet of any of claims 1-8 and 11-18.