CN113789008B

CN113789008B - Superstrong continuous fiber reinforced polyolefin composite material and preparation method thereof

Info

Publication number: CN113789008B
Application number: CN202111177776.7A
Authority: CN
Inventors: 吴摞; 王雷; 李荣群
Original assignee: Hefei Yuanrong New Material Co ltd
Current assignee: Hefei Yuanrong New Material Co ltd
Priority date: 2021-10-09
Filing date: 2021-10-09
Publication date: 2022-12-13
Anticipated expiration: 2041-10-09
Also published as: CN113789008A

Abstract

The invention discloses a superstrong continuous fiber reinforced polyolefin composite material and a preparation method thereof, wherein the material consists of polyolefin, glass fiber, compatilizer, glass powder, coupling agent, light stabilizer, antioxidant and lubricant; wherein the glass fibers are continuous fibers; the glass powder is boron glass powder with low melting point, and the grain diameter of the glass powder is 1-2 mu m. The preparation method of the material comprises the following steps: after the polyolefin, the compatilizer, the light stabilizer, the antioxidant and the lubricant are premixed according to a certain proportion, the mixture is melted, mixed and extruded into an infiltration mold through a double-screw extruder, the mixture and the specially-treated continuous glass fiber are fully melted and infiltrated in the mold, and the fully-impregnated continuous fiber reinforced polyolefin sheet passes through a cooling and shaping device and a winding device to realize the continuous production of the composite material. Due to the combination optimization of the interface of the fiber and the resin, the prepared composite material has ultrahigh mechanical strength.

Description

Superstrong continuous fiber reinforced polyolefin composite material and preparation method thereof

Technical Field

The invention relates to the technical field of high polymer materials, in particular to a superstrong continuous fiber reinforced polyolefin composite material and a preparation method thereof.

Background

With the improvement of social development level and the enhancement of energy conservation, emission reduction, environmental protection and sustainable development consciousness, the fields of aerospace, rail transit, buildings, automobiles, household appliances and the like all put forward high-performance and light-weight requirements on materials. A single material has not been able to meet the practical needs of many areas and research has begun to turn the field of view gradually towards more prominent composite materials. Fiber reinforced resin based composite materials are developed in the united states from the last 30 th century, composite products at that time mainly meet the requirements of the military industry and the aerospace field, and are mainly classified into thermosetting types and thermoplastic types at present.

In the thermoplastic composite material type, compared with short fiber and long fiber reinforced thermoplastic composite materials, the continuous fiber reinforced thermoplastic composite material has more excellent mechanical properties and can be used as a structural material; in addition, the steel material has the advantages of light weight, corrosion resistance and the like, and has great potential. The tensile strength of Polyolefin (PO) is generally 20-30MPa, the tensile strength of long glass fiber reinforced polyolefin (LFTPO) is 100-150MPa, which is 3-5 times of that of pure resin, and the tensile strength of the conventional unidirectional continuous glass fiber reinforced sheet can reach 700-800MPa, although the strength is high, the performance still needs to be further improved for some application fields with very high requirements on weight, size and mechanics. At present, many researches on continuous fiber reinforced polyolefin composite materials have been conducted, but most of the researches are focused on the development of some special functional materials and sheets, such as low dielectric constant (CN 106543554A), low odor (CN 103374178A), flame retardant (CN 102532681A), surface decoration (CN 103963395A), composite boards (CN 103568396A, CN 107877991A), and relatively few researches on the improvement of the tensile strength of unidirectional tapes.

Disclosure of Invention

The invention aims to provide a superstrong continuous fiber reinforced polyolefin composite material and a preparation method thereof, which have higher tensile strength and basically unchanged process compared with the existing continuous fiber reinforced polyolefin composite material, and are suitable for batch continuous production.

The purpose of the invention can be realized by the following technical scheme:

an ultra-strong continuous fiber reinforced polyolefin composite material comprises the following components in parts by weight:

further, the polyolefin is one of polypropylene and polyethylene, the melt index of the polyolefin is 50-70g/10min, and the test condition of the melt index of the polypropylene is 230 ℃ and 2.16kg; the polyethylene melt index test condition is 190 ℃ and 2.16kg.

Furthermore, the continuous glass fiber belongs to alkali-free glass fiber, and the alkali-free glass fiber has good electrical insulation and mechanical properties.

Further, the compatilizer is at least one of a cyclic anhydride grafted compatilizer and a carboxylic acid grafted compatilizer.

Furthermore, the light stabilizer is a benzotriazole light stabilizer, the benzotriazole light stabilizer can absorb ultraviolet rays with the wavelength of 270-380 nm, has good chemical stability, extremely small volatility and good compatibility with polyolefin, and is combined with an antioxidant to form a remarkable synergistic effect so as to improve the thermal-oxidative stability of the product.

Further, the antioxidant is a compound antioxidant, and the compound antioxidant is prepared by mixing a phenol-resistant antioxidant: the volume ratio of the phosphite ester antioxidant is as follows: 1: (1.5-2) are compounded.

Furthermore, the lubricant is a fatty acid amide lubricant which has good chemical stability, high melting point, convenient processing, excellent external lubrication effect and stripping property, good transparency, dispersity, glossiness and electric insulation property, no toxicity and good compatibility with polyolefin.

A preparation method of a super-strong continuous fiber reinforced polyolefin composite material comprises the following steps:

s1, adding polyolefin resin, a compatilizer, a light stabilizer, an antioxidant and a lubricant into a high-speed mixer at the temperature of 65-75 ℃ together according to the proportion, and mixing for 5-10min;

s2, continuous glass fibers enter a yarn spreading device for fiber strand dispersion through yarn releasing and guide rollers, low-melting-point glass powder suspension is sprayed on the surface of the yarn spreading rear section, so that micron low-melting-point glass powder can be attached to fiber strands while the fiber strands are dispersed, and then the fiber strands continuously enter a high-temperature furnace for baking for 5-10S through the guide rollers, wherein the temperature of the high-temperature furnace is as follows: 400-450 ℃, and then the mixture is guided into a dipping die through another guide roller;

and S3, under the protection of nitrogen, adding the materials in the step S1 into a main feeding port of a double-screw extruder, performing melt mixing extrusion on the materials in the step S1 through the double-screw extruder, performing shunting on the materials and performing melt impregnation on the materials and the continuous fibers treated in the step S2, cooling and shaping the fully-impregnated continuous fiber bundles through a cooling and shaping device, and performing continuous production under the driving of a traction and winding device, wherein the temperature of the double-screw extruder is 220-235 ℃, the rotating speed of a screw is 450-500RPM, the vacuum degree is-0.04-0.1 MPa, and the temperature of the impregnation die is 230-240 ℃.

Further, the low-melting-point glass powder is subjected to high-speed stirring and dispersing treatment by using a coupling agent, the mass ratio of the coupling agent to the low-melting-point glass powder is 0.002-0.0025, and the stirring rotating speed is as follows: 1000-1200r/min for 40-50min, then adding the surface-treated micron low-melting-point glass powder into water to prepare a solution with the micron low-melting-point glass powder accounting for 1-1.5%, then carrying out ultrasonic treatment for 1-1.5h with the ultrasonic frequency of 28kHz or 40kHz to obtain a low-melting-point glass powder suspension, carrying out high-speed stirring and dispersing treatment to remove the agglomeration among the low-melting-point glass powder particles, and uniformly dispersing the low-melting-point glass powder particles on the surface of glass fibers in the spraying process.

Further, the coupling agent is at least one of 3-aminopropyltriethoxysilane or 3-glycidoxypropyltrimethoxysilane; the grain size of the micron low-melting-point glass powder is 1-2 mu m, and the melting point is 350-400 ℃.

The invention has the beneficial effects that:

1. after the continuous glass fiber after the composite material is subjected to spreading and spraying and heating treatment by using a low-melting-point glass powder suspension, the micron glass micropowder is slightly melted and adhered to the smooth surface of the glass fiber to form a glass fiber surface with certain roughness, and the rough surface can form a strong mechanical engagement effect at the interface of the fiber and resin, so that the tensile strength of the unidirectional tape can be greatly increased;

2. the organic-inorganic interface action of the active group compatilizer in the composite material is enhanced; the compatilizer added into the resin can increase active reaction groups in the resin matrix, so that the resin matrix can be effectively combined with inorganic micron glass micro powder and continuous glass fibers, the bonding force of an interface is enhanced, and the tensile strength of the unidirectional tape is improved.

Detailed Description

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

Example 1

s1, adding 35 kg of polypropylene resin, 4 kg of cyclic anhydride grafted compatilizer, 0.2 kg of benzotriazole light stabilizer, 0.2 kg of compound antioxidant and 0.2 kg of lubricant into a high-speed mixer at the temperature of 65 ℃ for mixing for 5min, wherein the compound antioxidant is prepared by mixing the following components in parts by weight: the volume ratio of the phosphite ester antioxidant is as follows: 1.5, and mixing; the lubricant is a fatty acid amide lubricant.

S2, carrying out high-speed stirring and dispersing treatment on the micron low-melting-point glass powder by using a coupling agent, wherein the mass ratio is as follows: coupling agent/low-melting glass powder =0.002, and the stirring speed is: 1200r/min for 40min, then adding the surface-treated micron low-melting-point glass powder into water to prepare a solution with the micron low-melting-point glass powder accounting for 1%, then carrying out ultrasonic treatment for 1h at the ultrasonic frequency of 28kHz to obtain a low-melting-point glass powder suspension, carrying out high-speed stirring and dispersing treatment to remove agglomeration among particles of the low-melting-point glass powder, and uniformly dispersing the particles on the surface of glass fibers in a spraying process, wherein the particle size of the micron low-melting-point glass powder is 1-2 mu m and the particle size of the micron low-melting-point glass powder is 1-2 mu m.

The coupling agent is 3-aminopropyl triethoxysilane.

S3, 59 kilograms of continuous glass fibers enter a yarn spreading device for fiber bundle dispersion through yarn releasing and guide rollers, 2 kilograms of low-melting-point glass powder suspension is sprayed on the surface of the rear yarn spreading section, so that micron low-melting-point glass powder can be attached to the fiber bundles while the fiber bundles are dispersed, then the fiber bundles are guided by the guide rollers to continuously enter a high-temperature furnace for baking for 5 seconds (micron low-melting-point glass micropowder is slightly melted and adhered to the surface of smooth glass fibers, and excessive water is evaporated therewith), the temperature of the high-temperature furnace is 400 ℃, and then the fiber bundles are guided by another guide roller to enter a dipping die;

and S4, under the protection of nitrogen, adding the materials in the step S1 into a main feeding port of a double-screw extruder, performing melt mixing extrusion on the materials in the step S1 through the double-screw extruder, performing shunting on the materials and the continuous fibers treated in the step S3, performing melt impregnation on the materials, cooling and shaping the fully impregnated continuous fiber bundles through a cooling and shaping device, and performing continuous production under the driving of a traction and winding device. In the processing process, the temperature of the double-screw extruder is 220 ℃, the rotating speed of the screw is 450RPM, the vacuum degree is-0.04 MPa, and the temperature of the dipping die is 230 ℃.

Comparative example 1

The difference from example 1 is that: does not contain a low-melting-point glass powder suspension.

Comparative example 2

The difference from example 1 is that: and the temperature of the high-temperature furnace in the S3 is 100 ℃.

Comparative example 3

The difference from example 1 is that: and S2, carrying out high-speed stirring and dispersing treatment on the micron glass powder with the melting point of 480-520 ℃ by using a coupling agent.

Example 2

s1, adding 37 kg of polyethylene resin, 5 kg of carboxylic acid grafted compatilizer, 0.3 kg of benzotriazole light stabilizer, 0.3 kg of compound antioxidant and 0.3 kg of lubricant into a high-speed mixer at the temperature of 75 ℃ for mixing for 10min, wherein the compound antioxidant is prepared by mixing the following components in parts by weight: the volume ratio of the phosphite ester antioxidant is as follows: 1, compounding the components in parts by weight; the lubricant is a fatty acid amide lubricant.

S2, carrying out high-speed stirring and dispersing treatment on the micron low-melting-point glass powder by using a coupling agent, wherein the mass ratio is as follows: coupling agent/low-melting glass powder =0.0025, and the stirring speed is as follows: 1000r/min for 50min, adding the surface-treated micron low-melting-point glass powder into water to prepare a solution with the micron low-melting-point glass powder accounting for 1.5%, performing ultrasonic treatment for 1.5h at the ultrasonic frequency of 40kHz to obtain a low-melting-point glass powder suspension, performing high-speed stirring and dispersing treatment to remove the agglomeration among the particles of the low-melting-point glass powder, uniformly dispersing the low-melting-point glass powder on the surface of glass fibers in a spraying process, wherein the particle size of the micron low-melting-point glass powder is 1-2 mu m, and the melting point is 350-400 ℃.

The coupling agent is 3-glycidyl ether oxypropyl trimethoxy silane.

S3, leading 61 kg of continuous glass fiber into yarn spreading equipment through yarn releasing and a guide roller to disperse fiber bundles, spraying 3 kg of low-melting-point glass powder suspension on the surface of the rear yarn spreading section to ensure that micron low-melting-point glass powder can be attached to the fiber bundles while the fiber bundles are dispersed, then leading the fiber bundles to continuously enter a high-temperature furnace through the guide roller to be baked for 10S (the micron low-melting-point glass micropowder is slightly melted and adhered to the surface of the smooth glass fiber, and the surplus water is evaporated along with the micron low-melting-point glass micropowder), wherein the temperature of the high-temperature furnace is 450 ℃, and then leading the fiber bundles to enter a dipping die through another guide roller;

s4: under the protection of nitrogen, adding the material in the step S1 into a main feeding port of a double-screw extruder, melting, mixing and extruding the material into an impregnation die through the double-screw extruder, shunting, melting and impregnating the material and the treated continuous fiber in the step S3, cooling and shaping the fully impregnated continuous fiber bundle through a cooling and shaping device, and carrying out continuous production under the driving of a traction and winding device. In the processing process, the temperature of the double-screw extruder is 235 ℃, the rotating speed of the screw is 500RPM, the vacuum degree is-0.1 MPa, and the temperature of the dipping die is 240 ℃.

Comparative example 4

The difference from example 2 is that: does not contain a low-melting-point glass powder suspension.

The polyolefin melt index is 50-70g/10min, and the polypropylene melt index test condition is 230 ℃ and 2.16kg; the polyethylene melt index test condition is 190 ℃ and 2.16kg.

The continuous glass fiber is alkali-free glass fiber.

Comparative example 5

The difference from example 2 is that: no compatibilizing agent is included.

The composite materials obtained in comparative examples 1 to 3, example 1 and example 2 were subjected to tensile strength tests, and the test results are shown in the following table; the composites obtained in examples 1 and 2 exhibit ultra high tensile strength. Example 1 tensile strength is higher than comparative example 1, which shows that the tensile strength of the low-melting glass micropowder to the continuous fiber is obviously improved; comparative example 2 and comparative example 3 are not much different in tensile strength and are all larger than comparative example 1, but all three are much lower than the tensile strength of comparative example 1, which shows that in the case of fusion adhesion of low-melting-point glass micropowder, although weak coupling action exists between the glass micropowder and continuous glass fiber, the high tensile strength in example 1 is derived from the fusion adhesion action of the low-melting-point glass micropowder and continuous glass fiber. The tensile strength of the comparative example 5 is far lower than that of the example 2, which shows that the compatibility between the organic resin matrix and the inorganic micron glass micro powder and the continuous glass fiber is poor, the tensile strength is low, and the compatibilization effect of the organic-inorganic interface of the compatilizer is very important for improving the tensile strength.

In the description herein, references to the description of "one embodiment," "an example," "a specific example," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

The foregoing shows and describes the general principles, essential features, and advantages of the invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are described in the specification and illustrated only to illustrate the principle of the present invention, but that various changes and modifications may be made therein without departing from the spirit and scope of the present invention, which fall within the scope of the invention as claimed.

Claims

1. The superstrong continuous fiber reinforced polyolefin composite material is characterized by comprising the following components in parts by weight;

stirring and dispersing the low-melting-point glass powder by using a coupling agent, wherein the mass ratio of the coupling agent to the low-melting-point glass powder is 0.002-0.0025, adding the micrometer low-melting-point glass powder subjected to surface treatment into water to prepare a solution with the micrometer low-melting-point glass powder accounting for 1-1.5%, and then carrying out ultrasonic treatment to obtain a low-melting-point glass powder suspension;

the preparation method of the composite material comprises the following steps:

s1, adding polyolefin resin, a compatilizer, a light stabilizer, an antioxidant and a lubricant into a high-speed mixer together according to a ratio, and mixing for 5-10min at 65-75 ℃;

s2, continuous glass fibers enter a yarn spreading device for fiber strand dispersion through yarn releasing and guide rollers, low-melting-point glass powder suspension is sprayed on the surface of the yarn spreading rear section, so that micron low-melting-point glass powder is attached to fiber strands while the fiber strands are dispersed, and then the fiber strands continuously enter a high-temperature furnace for baking for 5-10S through guide rollers, wherein the temperature of the high-temperature furnace is as follows: 400-450 ℃, and then the mixture is guided into a dipping die through another guide roller;

s3, under the protection of nitrogen, adding the materials in the S1 into a main feeding port of a double-screw extruder, performing melt mixing extrusion on the materials in the double-screw extruder, performing shunt on the materials and performing melt impregnation on the continuous fibers after treatment in the S2, cooling and shaping the fully-impregnated continuous fiber bundles by a cooling and shaping device, and performing continuous production under the driving of a traction and winding device, wherein the temperature of the double-screw extruder is 220-235 ℃, the rotating speed of a screw is 450-500RPM, the vacuum degree is-0.04-0.1 MPa, and the temperature of the impregnation die is 230-240 ℃;

the coupling agent is at least one of 3-aminopropyltriethoxysilane or 3-glycidyl ether oxypropyltrimethoxysilane; the grain size of the micron low-melting-point glass powder is 1-2 mu m, and the melting point is 350-400 ℃.

2. The super-strong continuous fiber reinforced polyolefin composite material according to claim 1, wherein the polyolefin is one of polypropylene and polyethylene, the melt index of the polyolefin is 50-70g/10min, the polypropylene melt index test condition is 230 ℃, and 2.16kg; the polyethylene melt index test conditions were 190 ℃ and 2.16kg.

3. The super strong continuous fiber reinforced polyolefin composite of claim 1, wherein the continuous glass fiber is alkali-free glass fiber.

4. The super-strong continuous fiber reinforced polyolefin composite material of claim 1, wherein the compatibilizer is at least one of a cyclic acid anhydride grafted compatibilizer and a carboxylic acid grafted compatibilizer.

5. The ultra-strong continuous fiber reinforced polyolefin composite material as claimed in claim 1, wherein the light stabilizer is a benzotriazole light stabilizer.

6. The super strong continuous fiber reinforced polyolefin composite of claim 1, wherein said lubricant is a fatty acid amide lubricant.

7. The ultra-strong continuous fiber reinforced polyolefin composite material according to claim 1, wherein the low-melting-point glass powder is stirred and dispersed by using a coupling agent at the following rotation speed: 1000-1200r/min for 40-50min, ultrasonic time for 1-1.5h and ultrasonic frequency of 28kHz or 40kHz, and stirring and dispersing to remove agglomeration among low-melting-point glass powder particles, and the glass powder particles can be uniformly dispersed on the surface of glass fibers in the spraying process.