CN115124826A

CN115124826A - Glass fiber reinforced polycarbonate material and preparation method and application thereof

Info

Publication number: CN115124826A
Application number: CN202210920280.2A
Authority: CN
Inventors: 刘春艳; 刘向东
Original assignee: Shanghai Zhonglei New Material Science Co ltd
Current assignee: Shanghai Zhonglei New Material Science Co ltd
Priority date: 2022-08-02
Filing date: 2022-08-02
Publication date: 2022-09-30
Also published as: WO2024027415A1

Abstract

The invention provides a glass fiber reinforced polycarbonate material and a preparation method and application thereof, wherein the glass fiber reinforced polycarbonate material comprises the following components in parts by weight: 40-95 parts of polycarbonate, 1-40 parts of alkali-free glass fiber and 1-40 parts of porous glass fiber; SiO in the porous glass fiber ₂ The mass percentage content of the compound is more than or equal to 95 percent. The invention compounds the alkali-free glass fiber with low dielectric loss and the porous glass fiber and modifies the polycarbonate, thus comprehensively improving the dielectric property, the mechanical property and the processability of the material, leading the material to have high impact toughness, good mechanical property and special processing propertyThe dielectric ceramic has good performance, lower dielectric loss and dielectric constant, and balanced performance in multiple aspects of excellent dielectric property, processability, comprehensive mechanical property and the like, and can meet the requirements in the fields of high-frequency communication equipment, automobile parts, electric appliances and the like.

Description

Glass fiber reinforced polycarbonate material and preparation method and application thereof

Technical Field

The invention belongs to the technical field of polymer materials, and particularly relates to a glass fiber reinforced polycarbonate material and a preparation method and application thereof.

Background

In recent years, with the proliferation of mobile devices, the operating frequency below 3G, which is commonly used by mobile communication providers, cannot meet the requirement, and the frequency band below 3GHz is becoming more and more congested. With the advent of the 5G era, wider frequency bands are deployed globally, and can be broadened from 3G to high-frequency 4.4-5GHz and millimeter waves 26-39GHz to achieve enhanced network services with high transmission rate, large-capacity signal propagation and low information delay. Under the signal transmission condition of 5G high-frequency electromagnetic waves, the wavelength of the transmitted electromagnetic waves is gradually shortened, and the diffraction capability is deteriorated, so that the number of 5G core base stations is required to be increased, and the dielectric constant and the dielectric loss of a propagation medium are low, so as to realize effective receiving and transmission. High-frequency high-speed transmission also puts requirements on composite materials used in smart phones, needs to have low dielectric loss under high-frequency voltage, and is also more suitable for processing and molding thin-walled parts; therefore, it is an urgent need to reduce the dielectric constant and dielectric loss of the material and improve the processing fluidity of the material, which is in the 5G new era.

Polycarbonate (PC) is a polymer containing a carbonate group in the main chain, has good mechanical properties, dimensional stability, heat resistance and insulating properties, is one of general engineering plastics, and can be applied to almost all plastic parts of smart phones, such as rear housings, middle frames, internal supporting frames, side keys and the like. However, most of the polycarbonates are aromatic polymers, have high molecular chain rigidity, low fatigue strength, are sensitive to notches, are easy to generate stress cracking, and have a large improvement space in toughness and strength, and the polycarbonates are reinforced by fiber fillers or other polymers, which is a conventional method in the industry.

CN105440628A discloses a reinforced flame-retardant PC/PPO composite material, which comprises the following components: 20-30 parts of PC resin, 14.9-22 parts of PPO (polyphenylene oxide), 3-5.2 parts of PC-PPO block copolymer, 5-8 parts of SEBS graft, 5-8 parts of polypropylene elastomer graft, 0.5-1 part of amino modified silicone oil, 0.5-1 part of aminosilane coupling agent and 20-30 parts of glass fiber; and composite flame retardant, antioxidant and light stabilizer. The composite material has good tensile strength, rigidity and high and low temperature toughness, but the PPO material has high viscosity and high rigidity, so that the material has low processing fluidity and is difficult to prepare thin-walled parts; and PPO has poor compatibility with PC and glass fiber, and the PPO needs to be pretreated, so that the cost is increased.

CN109206875A discloses a polycarbonate composition, which comprises the following components: 50-90% of polycarbonate, 5-45% of glass fiber group and 0-5% of auxiliary agent; the glass fiber group is one or the combination of two of long glass fiber or short glass fiber. The polycarbonate composition adopts glass fibers with different lengths to toughen and modify PC and improve the flatness of materials, but the used glass fibers comprise M-glass fibers, E-glass fibers, A-glass fibers, S-glass fibers, R-glass fibers or C-glass fibers and the like, and the glass fibers have high dielectric constant and dielectric loss, so that the dielectric property of the polycarbonate composition is poor and the performance requirements of high-frequency electronic equipment are difficult to meet.

CN101875772A discloses a glass fiber reinforced PC composite material, which comprises the following components: 45-61% of polycarbonate, 5-20% of saturated polyester, 3-4% of toughening agent, 0.1-0.3% of heat stabilizer, 0.7-1.1% of lubricant and 25-35% of glass fiber. The composite material has good toughness, strength and surface smoothness, but the notch impact strength is below 180J/m, the impact toughness is poor, the dielectric constant and the dielectric loss are high, and the composite material is not beneficial to application in high-frequency electronic equipment.

Therefore, it is important to improve the impact toughness, processability and dielectric properties of polycarbonate materials and reduce the dielectric loss of the materials in the field.

Disclosure of Invention

Aiming at the defects of the prior art, the invention aims to provide a glass fiber reinforced polycarbonate material and a preparation method and application thereof, wherein the polycarbonate is modified by compounding alkali-free glass fibers and porous glass fibers, so that the glass fiber reinforced polycarbonate material has lower dielectric loss, higher impact strength and good processing characteristics, and fully meets the performance requirements of composite materials in the fields of high-frequency high-speed communication equipment, automobile parts, electric appliances and the like.

In order to achieve the purpose, the invention adopts the following technical scheme:

in a first aspect, the invention provides a glass fiber reinforced polycarbonate material, which comprises the following components in parts by weight:

40-95 parts of Polycarbonate (PC)

1-40 parts of alkali-free glass fiber

1-40 parts of porous glass fiber;

SiO in the porous glass fiber ₂ The mass percentage content of the compound is more than or equal to 95 percent.

In the glass fiber reinforced polycarbonate material provided by the invention, alkali-free glass fiber and porous glass fiber are compounded and polycarbonate is modified; wherein the alkali-free glass fiber comprises SiO ₂ And part of Al ₂ O ₃ 、B ₂ O ₃ CaO and the like, and substantially no MgO or Li ₂ O、Na ₂ O、K ₂ O and TiO ₂ Low dielectric constant and low dielectric loss; the porous glass fiber contains a large number of microscopic pores, SiO ₂ The content of the high-dielectric-constant-strength glass fiber is more than or equal to 95%, the high-dielectric-constant-strength glass fiber has extremely low dielectric constant and dielectric loss, and the existence of the holes enhances the binding property of the glass fiber and the matrix PC, so that the processing characteristic of the material can be remarkably improved, the material can obtain energy buffering when being subjected to external impact, and the impact toughness of the material is greatly improved. The glass fiber reinforced polycarbonate material is compounded by specific glass fiber and polycarbonate, so that the low dielectric constant and low dielectric loss are endowed, the processability, strength, toughness and impact resistance of the material are improved, and meanwhile, due to the good combination of the polycarbonate and a filler (alkali-free glass fiber and porous glass fiber), the condition of fiber floating on the surface is greatly improved, and the glass fiber reinforced polycarbonate material has excellent dielectric property and comprehensive mechanical property.

In the glass fiber reinforced polycarbonate material, the weight part of the polycarbonate is 40 to 95 parts, for example, 45 parts, 50 parts, 55 parts, 60 parts, 65 parts, 70 parts, 75 parts, 80 parts, 85 parts or 90 parts, and specific values therebetween are limited by space and for the sake of brevity, and the invention is not exhaustive and does not include specific values within the range, preferably 55 to 85 parts, and more preferably 60 to 80 parts.

The alkali-free glass fiber is 1 to 40 parts by weight, for example, 3 parts, 5 parts, 8 parts, 10 parts, 12 parts, 15 parts, 18 parts, 20 parts, 22 parts, 25 parts, 28 parts, 30 parts, 32 parts, 35 parts or 38 parts by weight, and specific values therebetween are not exhaustive, and for reasons of brevity, the invention is not intended to list the specific values included in the range, preferably 3 to 30 parts, and more preferably 5 to 25 parts.

The porous glass fiber is 1 to 40 parts by weight, for example, 3 parts, 5 parts, 8 parts, 10 parts, 12 parts, 15 parts, 18 parts, 20 parts, 22 parts, 25 parts, 28 parts, 30 parts, 32 parts, 35 parts or 38 parts by weight, and specific points between the above points are not exhaustive, and for the sake of brevity, the invention does not include the specific points included in the range, preferably 3 to 30 parts, and more preferably 5 to 25 parts.

SiO in the porous glass fiber ₂ The content of (b) is not less than 95% by mass, and may be, for example, 95.5%, 96%, 96.5%, 97%, 97.5%, 98%, 98.5%, 99% or the like.

Preferably, the polycarbonate comprises bisphenol a polycarbonate.

Preferably, the polycarbonate has a melt index of 5 to 40g/10min, for example, 8g/10min, 10g/10min, 15g/10min, 20g/10min, 25g/10min, 30g/10min, 35g/10min or 38g/10min at 300 ℃ and 1.2kg, and specific values therebetween, which are not intended to be exhaustive for the purpose of disclosure and brevity and are not intended to be exhaustive.

Preferably, SiO in the alkali-free glass fiber ₂ The content of (b) is not less than 90% by mass, and may be, for example, 90.5%, 91%, 91.5%, 92%, 92.5%, 93%, 93.5%, 94%, 94.5%, 95%, 95.5%, 96%, 96.5%, 97%, 97.5%, 98%, 98.5% or 99%.

The glass fiber has various types and generally contains a large amount of polar groups, so that the dielectric constant and the dielectric loss are high; the commonly used glass fiber filler at present comprises E-glass fiber, D-glass fiber and the like. The E-glass fiber is borosilicate glass fiber, has good electrical insulation performance and mechanical performance, but has poor dielectric property, and the dielectric constant D is 1MHz _k 3.3-3.6, dielectric loss D _f Is 0.009; the D-glass fiber belongs to short-cut low dielectric glass fiber,less polar groups in the structure composition, lower dielectric loss than E-glass fiber, and dielectric constant D at 1MHz _k 4.2-4.8, dielectric loss D _f Is 0.001. In general, the glass fiber used for resin reinforcement has a dielectric constant D at room temperature of 1MHz _k Typically 3.5 to 6, dielectric loss D _f Is 0.0032; added to a PC resin matrix, the PC resin has a dielectric constant D _k 2.8 to 3.2, dielectric loss D _f 0.002-0.001; the dielectric loss increases under high frequency conditions. The dielectric loss of the conventional glass fiber reinforced PC material is within the range of 0.01-0.02 at 5GHz, and the conventional glass fiber reinforced PC material cannot meet the requirements of communication equipment in the 5G era on polymer modified engineering plastics. As a preferable embodiment of the present invention, the alkali-free glass fiber contains 90% or more of SiO ₂ And part of Al ₂ O ₃ 、B ₂ O ₃ CaO and the like, and substantially no MgO or Li ₂ O、Na ₂ O、K ₂ O and TiO ₂ The dielectric constant and dielectric loss are low, and the dielectric loss is extremely low especially at high frequency (5 GHz).

Preferably, the alkali-free glass fiber has a dielectric loss at 5GHz in the range of 0.0030 to 0.0035, which may be, for example, 0.0031, 0.0032, 0.0033 or 0.0034, and specific values therebetween, not to be exhaustive, for reasons of brevity and clarity.

Preferably, the dielectric constant of the alkali-free glass fiber at 5GHz is 4.2-4.8, and may be, for example, 4.25, 4.3, 4.35, 4.4, 4.45, 4.5, 4.55, 4.6, 4.65, 4.7, or 4.75, and specific values therebetween, and for brevity and clarity, the present invention is not exhaustive of the specific values included in the range.

Preferably, the pore size of the porous glass fiber is 0.5 to 3 μm, and may be, for example, 0.55 μm, 0.6 μm, 0.8 μm, 1 μm, 1.2 μm, 1.5 μm, 1.8 μm, 2 μm, 2.2 μm, 2.5 μm or 2.8 μm, and specific values therebetween are not exhaustive, and the invention is not limited to the specific values included in the range for brevity and conciseness.

Preferably, the porous glass fiberThe specific surface area of the fiber is 300-600m ² A/g of, for example, 320m ² /g、350m ² /g、380m ² /g、400m ² /g、420m ² /g、450m ² /g、480m ² /g、500m ² /g、520m ² /g、550m ² G or 580m ² The present invention is not intended to be exhaustive of the specific point values included in the ranges, limited to space and for the sake of brevity, as well as the specific point values between the point values recited above.

As a preferable technical solution of the present invention, SiO in the porous glass fiber ₂ The content is more than or equal to 95 percent, and the porous glass fiber contains a large number of microscopic holes (air, the dielectric constant is 1, and the dielectric loss is 0), so that the porous glass fiber has low dielectric constant and dielectric loss; moreover, the micropores in the porous glass fiber can generate a capillary phenomenon, so that the bonding property with PC resin in a molten state is enhanced, and the processing property and the comprehensive mechanical property of the material are greatly improved. In addition, because the PC resin has the non-Newtonian fluid characteristic of the high molecular polymer in a molten state, the molten PC cannot completely enter the porous glass fiber, and enough air components are reserved, so that the glass fiber reinforced polycarbonate material is endowed with lower dielectric constant and dielectric loss.

Preferably, the dielectric loss of the porous glass fiber at 5GHz is 0.002-0.003, for example, 0.0021, 0.0023, 0.0024, 0.0025, 0.0026, 0.0027, 0.0028 or 0.0029, and specific values therebetween are not exhaustive for the invention, which is not intended to limit the scope and simplicity.

Preferably, the dielectric constant of the porous glass fiber at 5GHz is 3.7-4.2, and may be, for example, 3.75, 3.8, 3.85, 3.9, 3.95, 4, 4.05, 4.1 or 4.15, and specific values therebetween, are not intended to be exhaustive, and for the sake of brevity and clarity, the invention is not intended to be exhaustive of the specific values included in the ranges.

Preferably, the mass ratio of the porous glass fibers to the alkali-free glass fibers is 1 (0.3-1.3), and may be, for example, 1:0.4, 1:0.5, 1:0.6, 1:0.7, 1:0.8, 1:0.9, 1:1, 1:1.1, 1:1.2, or the like.

As a preferred technical scheme of the invention, the mass ratio of the porous glass fiber to the alkali-free glass fiber is 1 (0.3-1.3), and the porous glass fiber and the alkali-free glass fiber are compounded, so that the glass fiber reinforced polycarbonate material has excellent dielectric property, toughness, strength and processability, and obtains good balance on comprehensive performance. If the mass ratio of the two exceeds the range, the excessive content of the porous glass fiber can influence the reinforcing and toughening effects of the glass fiber on the PC resin, so that the mechanical properties of the glass fiber reinforced polycarbonate material are slightly reduced; the content of the alkali-free glass fiber is too high, so that the dielectric loss of the material is increased.

Preferably, the sum of the alkali-free glass fiber and the porous glass fiber in the glass fiber reinforced polycarbonate material is 5-50% by mass, for example, 8%, 10%, 15%, 20%, 25%, 30%, 35%, 40% or 45%, and the specific values therebetween are limited by space and for brevity, the invention is not exhaustive.

Preferably, the porous glass fiber is obtained by pore-forming reinforced glass fiber in an acid solution.

Preferably, the young's modulus of the reinforced glass fiber is 50-90GPa, such as 55GPa, 60GPa, 65GPa, 70GPa, 75GPa, 80GPa or 85GPa, and specific values therebetween, limited to space and for brevity, the present invention is not exhaustive of the specific values included in the ranges.

Preferably, the ratio of the strength of the porous glass fibers to the reinforcing glass fibers is (0.5-0.8):1, and may be, for example, 0.52:1, 0.55:1, 0.58:1, 0.6:1, 0.62:1, 0.65:1, 0.68:1, 0.7:1, 0.72:1, 0.75:1, or 0.78:1, etc.

Preferably, the porous glass fiber is obtained by pore-forming reinforced glass fiber; compared with the original reinforced glass fiber after pore forming, the strength of the porous glass fiber can be kept between 50 and 80 percent, and the specific surface area is from 1m ² Lifting/g to 300-600m ² /g。

Preferably, the porous glass fiber is prepared by a method comprising: and sequentially treating the reinforced glass fiber in an acid solution and an alkaline salt solution, and drying to obtain the porous glass fiber.

Preferably, the pH of the acid solution is 2-5, for example, 2.2, 2.5, 2.8, 3, 3.2, 3.5, 3.8, 4, 4.2, 4.5 or 4.8, and the specific values therebetween are not exhaustive for the sake of brevity and clarity.

Preferably, the acid solution includes any one of a hydrochloric acid solution, a sulfuric acid solution, or a nitric acid solution, or a combination of at least two thereof.

Preferably, the treatment time in the acid solution is 1 to 8 hours, for example, 1.25 hours, 1.5 hours, 1.75 hours, 2 hours, 2.25 hours, 2.5 hours, 2.75 hours, 3 hours, 3.25 hours, 3.5 hours, 3.75 hours, 4 hours, 4.25 hours, 4.5 hours, 4.75 hours, 5 hours, 5.25 hours, 5.5 hours, 5.75 hours, 6 hours, 6.5 hours, 7 hours or 7.5 hours, and specific values therebetween, which are limited in space and included in the range for brevity, are not exhaustive.

Preferably, the treatment temperature in the acid solution is between 30 and 80 ℃, for example 35 ℃, 40 ℃, 45 ℃, 50 ℃, 55 ℃, 60 ℃, 65 ℃, 70 ℃ or 75 ℃, and specific values therebetween, are not exhaustive for the invention and for reasons of brevity.

Preferably, the treatment in the acid solution is performed under stirring conditions.

Preferably, the acid solution treatment further comprises a cleaning step.

Preferably, the alkaline salt solution has a pH of 7.5 to 9, which may be, for example, 7.6, 7.8, 8, 8.1, 8.3, 8.5, 8.7 or 8.9, and the specific values therebetween, are not exhaustive for the purpose of brevity and clarity.

Preferably, the salt in the basic salt solution comprises an acid salt.

Preferably, the acid salt comprises any one of sodium bicarbonate, potassium bicarbonate or sodium bicarbonate borate or a combination of at least two thereof.

Preferably, the treatment time in the alkaline salt solution is 0.5 to 6h, for example, 0.75h, 1h, 1.25h, 1.5h, 1.75h, 2h, 2.25h, 2.5h, 2.75h, 3h, 3.25h, 3.5h, 3.75h, 4h, 4.25h, 4.5h, 4.75h, 5h, 5.25h, 5.5h or 5.75h, and specific values therebetween, are not exhaustive and for the sake of brevity, the invention does not exclude specific values included in the range.

Preferably, the treatment temperature in the alkaline salt solution is 30-80 ℃, for example, 35 ℃, 40 ℃, 45 ℃, 50 ℃, 55 ℃, 60 ℃, 65 ℃, 70 ℃ or 75 ℃, and the specific values therebetween are limited by space and for the sake of brevity, and the invention is not intended to be exhaustive of the specific values included in the ranges.

Preferably, the alkaline salt solution treatment further comprises a cleaning step.

Preferably, the drying temperature is 400-.

Preferably, the drying time is 0.5-2h, for example, 0.75h, 1h, 1.25h, 1.5h or 1.75h, and the specific values therebetween are not exhaustive for the invention, which is limited to the space and for brevity.

As a preferred technical scheme of the invention, the preparation of the porous glass fiber comprises the steps of sequentially carrying out acid solution treatment, alkaline salt solution treatment and drying on the reinforced glass fiber; the treatment of the acid solution will enhance the Na content of the glass fibers ⁺ 、K ⁺ When the alkali metal is gradually dissolved, micropores with different degrees and numbers are generated in the glass fiber along with different processing time, and the processing time in the acid solution is controlled to be 1-6h, so that the number, the shape and the glass fiber strength of the micropores are controlled; centrifugally cleaning the product treated by the acid solution to remove the solutionThen, carrying out acid salt solution treatment, hydrolyzing to generate OH-ions, neutralizing and diluting the residual acid solution, and thoroughly cleaning the added solution to ensure the purity of the product; after the treatment is finished, performing multiple rounds of centrifugal cleaning, and drying at the temperature of 400-700 ℃, wherein the polar hydroxyl free radicals are easy to remain on the surface of the glass fiber due to the fact that water and the glass are easy to form hydrated glass, so that the porous glass fiber is obtained by adopting the high temperature of 400-700 ℃.

Preferably, the glass fiber reinforced polycarbonate material further comprises 0.1 to 1 part of a toughening agent in parts by weight, for example, the toughening agent may be 0.2 part, 0.3 part, 0.4 part, 0.5 part, 0.6 part, 0.7 part, 0.8 part or 0.9 part, and specific values therebetween, and for reasons of brevity and brevity, the invention is not exhaustive and specific values included in the range are further preferably 0.1 to 0.5 part.

Preferably, the toughening agent includes any one of methyl methacrylate-butadiene-styrene copolymer (MBS), maleic anhydride grafted ethylene-octene copolymer elastomer, ethylene-butyl acrylate-glycidyl methacrylate copolymer, ethylene-methyl acrylate-glycidyl methacrylate copolymer or methyl methacrylate-styrene-silicone copolymer or a combination of at least two thereof.

Preferably, the glass fiber reinforced polycarbonate material further comprises 0.3 to 10 parts by weight of a coupling agent, for example, the coupling agent may be 0.5 part, 1 part, 1.5 parts, 2 parts, 2.5 parts, 3 parts, 3.5 parts, 4 parts, 4.5 parts, 5 parts, 5.5 parts, 6 parts, 7 parts, 8 parts or 9 parts, and specific points between the above points are limited to space and simplicity, so that the invention does not exhaust the specific points included in the range, and further preferably 0.5 to 6.5 parts.

As a preferred technical scheme of the invention, the coupling agent carries out surface treatment on the alkali-free glass fiber and the porous glass fiber, and further improves the compatibility and the binding property of the glass fiber and a PC resin matrix, so that the overall mechanical property and the dielectric property of the glass fiber reinforced polycarbonate material are improved.

Preferably, the coupling agent comprises any one of a silane coupling agent, a titanate coupling agent, or an aluminate coupling agent, or a combination of at least two thereof.

Preferably, the silane coupling agent includes any one of or a combination of at least two of gamma-aminopropyltrimethoxysilane, gamma-aminopropyltriethoxysilane, gamma-glycidoxypropyltrimethoxysilane, or gamma-glycidoxypropyltriethoxysilane.

Preferably, the titanate coupling agent comprises isopropyldioleacyloxy (dioctylphosphoryloxy) titanate.

Preferably, the glass fiber reinforced polycarbonate material further comprises 0.01-5 parts of antioxidant by weight, for example, the antioxidant can be 0.03 part, 0.05 part, 0.08 part, 0.1 part, 0.3 part, 0.5 part, 0.8 part, 1 part, 1.5 part, 2 parts, 2.5 parts, 3 parts, 3.5 parts, 4 parts or 4.5 parts, and specific values between the above values are limited by space and for simplicity, the invention does not list the specific values included in the range, and further preferably 0.01-0.5 part.

Preferably, the antioxidant comprises any one of hindered phenol antioxidant, hindered amine antioxidant, phosphite antioxidant or thioester antioxidant or a combination of at least two of the foregoing.

Preferably, the hindered phenol antioxidant includes n-octadecyl beta- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionate (antioxidant 1076), 2, 6-tributyl-4-methylphenol, bis (3, 5-tributyl-4-hydroxyphenyl) sulfide, 2, 6-di-tert-butyl-p-cresol, 1,3, 5-trimethyl-2, 4,6- (3, 5-di-tert-butyl-4-hydroxybenzyl) benzene, 1,3, 5-tris (3, 5-di-tert-butyl-4-hydroxybenzyl) isocyanuric acid, 2' -thiobis (4-methyl-6-tert-butylphenol), diethylene glycol bis-beta- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionate, and mixtures thereof, 4,4' -butylidene-bis (2- (1, 1-dimethylethyl) -5-methyl) phenol, octadecyl (3, 5-dibutyl-4-hydroxy-phenylpropionate), pentaerythritol tetrakis (β - (3, 5-di-t-butyl-4-hydroxyphenyl) propionate) (antioxidant 1010), or diethylene glycol bis (β - (3-t-butyl-4-hydroxy-5-methylphenyl) propionate), or a combination of at least two thereof.

Preferably, the aromatic amine-based antioxidant comprises N, N' -bis (3- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionyl) hexamethylenediamine (antioxidant 1098).

Preferably, the phosphite antioxidant includes any one of tris (2, 4-di-tert-butylphenyl) phosphite (antioxidant 168), bis (2, 4-di-tert-butylphenyl) pentaerythritol diphosphite (antioxidant 626), pentaerythritol distearyl diphosphite or tetrakis (2, 4-di-tert-butylphenyl-4, 4' -biphenyl) bisphosphate or a combination of at least two thereof.

Preferably, the glass fiber reinforced polycarbonate material further comprises 0.01-5 parts by weight of lubricant, for example, the lubricant may be 0.03 part, 0.05 part, 0.08 part, 0.1 part, 0.3 part, 0.5 part, 0.8 part, 1 part, 1.5 part, 2 parts, 2.5 parts, 3 parts, 3.5 parts, 4 parts or 4.5 parts, and specific point values between the above point values are limited by space and for the sake of brevity, the invention does not list the specific point values included in the range, and further preferably 0.01-0.5 part.

Preferably, the lubricant comprises any one of pentaerythritol stearate (e.g. PETS), a vinyl wax or a silicone oil or a combination of at least two thereof.

Preferably, the glass fiber reinforced polycarbonate material comprises the following components in parts by weight:

in a second aspect, the present invention provides a method for preparing a glass fiber reinforced polycarbonate material according to the first aspect, the method comprising: mixing polycarbonate, alkali-free glass fiber and porous glass fiber, and then melting and extruding to obtain the glass fiber reinforced polycarbonate material.

Preferably, the melt extrusion temperature is 240-.

Preferably, the melt extrusion is carried out in a screw extruder.

Preferably, the screw speed of the screw extruder is 350-750rpm, for example 400rpm, 450rpm, 500rpm, 550rpm, 600rpm, 650rpm or 700rpm, and specific values therebetween, for reasons of brevity and clarity, are not exhaustive and specific values encompassed by the scope of the invention are not provided.

Preferably, the mixing is performed in a blender.

Preferably, the mixing speed is 300-700rpm, for example, 350rpm, 400rpm, 450rpm, 500rpm, 550rpm, 600rpm or 650rpm, and specific values therebetween are limited for brevity and conciseness, and the invention is not exhaustive.

Preferably, the mixing time is 3-15min, for example 4min, 5min, 6min, 8min, 10min, 12min or 14min, and the specific values therebetween are limited for space and simplicity, and the invention is not intended to be exhaustive.

Preferably, the mixed material further comprises any one or a combination of at least two of a toughening agent, a coupling agent, an antioxidant or a lubricant.

Preferably, the polycarbonate is pre-baked prior to mixing at a temperature of 100-.

Preferably, the melt extrusion further comprises the steps of cooling, drying and granulating.

In a third aspect, the present invention provides a use of the glass fiber reinforced polycarbonate material according to the first aspect in communication equipment, automobile parts or electric appliance housings.

Compared with the prior art, the invention has the following beneficial effects:

in the glass fiber reinforced polycarbonate material provided by the invention, the alkali-free glass fiber with low dielectric loss and the porous glass fiber are compounded and the polycarbonate is modified, so that the dielectric property, the mechanical property and the processability of the material are comprehensively improved, the tensile strength is more than or equal to 105MPa, the elongation at break is 4.2-6%, the bending modulus is more than or equal to 5600MPa, the bending strength is more than or equal to 170MPa, the cantilever beam notch impact strength is 198-220J/m, the impact toughness is high, the mechanical property is good, the melt index at 300 ℃ and 1.2mm is 9.6-15g/10min, the processing property is good, the dielectric loss and the dielectric constant are lower, the dielectric constant at 5GHz is less than or equal to 3.25, and the dielectric loss is 0.0015-0.0042. The glass fiber reinforced polycarbonate material has excellent comprehensive mechanical properties such as dielectric property, processability, toughness, strength, impact resistance and the like, obviously improves the conditions of surface fiber floating and the like, and can meet the performance requirements in the fields of high-frequency communication equipment, automobile parts, electric appliances and the like.

Detailed Description

The technical solution of the present invention is further explained by the following embodiments. It should be understood by those skilled in the art that the examples are only for the understanding of the present invention and should not be construed as the specific limitations of the present invention.

Preparation example 1

A porous glass fiber G1 is prepared by the following method:

(1) soaking the water-washed reinforced glass fiber (Young modulus 90GPa) into a hydrochloric acid solution with the pH value of 2.0, treating for 1h under the condition of stirring at 60 ℃, and centrifugally cleaning to remove the solution to obtain the alkali-removed reinforced glass fiber;

(2) immersing the alkali-removed reinforced glass fiber obtained in the step (1) into a sodium bicarbonate solution with the pH value of 8.0 for treatment for 2 hours, and then carrying out centrifugal treatment to remove the solution; centrifugal cleaning is carried out for more than 10 times by using deionized water to obtain a porous glass fiber prefabricated product;

(3) and (3) carrying out air blast drying on the porous glass fiber prefabricated product obtained in the step (2) at the temperature of 600 ℃ for 0.8h to obtain the porous glass fiber G1.

Preparation examples 2 to 9

A porous glass fiber G2-G9, which differed from preparation example 1 only in that the process parameters were different, as shown in Table 1A and Table 1B.

The following performance tests were performed on the porous glass fibers provided in preparation examples 1 to 9, and untreated reinforced glass fibers (designated as G0) were used for comparison:

(1) pore size: testing the morphology of the porous glass fiber by adopting a Scanning Electron Microscope (SEM), and counting the pore particle size;

(2) specific surface area: testing by adopting SEM, and performing statistical calculation;

(3) dielectric constant D _k And dielectric loss D _f : testing by adopting an SPDR resonant cavity method;

(4) young's modulus: testing was carried out using the method of standard GB/T7962.6, testing Young's modulus before and after drying (i.e.step (3)) respectively;

the test results are shown in tables 1A and 1B:

TABLE 1A

TABLE 1B

In Table 1B, "- -" represents that the step was not performed; the young's modulus of G0 is the initial young's modulus of the reinforced glass fiber.

According to the performance test data in tables 1A and 1B, the reinforced glass fiber is dried after being sequentially treated in the acid solution and the acid salt solution, so that the porous glass fiber with low dielectric loss and a large amount of microscopic holes can be obtained; meanwhile, according to preparation examples 1 to 7, further adjustment and optimization of properties such as dielectric loss, Young modulus and the like of the porous glass fiber can be realized by adjusting process parameters such as treatment temperature, treatment time and the like. The porous glass fiber G8 of preparation example 8 was not treated with an acid salt solution in the preparation, resulting in a porous glass fiber having a large dielectric constant and dielectric loss; the porous glass fiber G9 of preparation example 9 was dried at too low a temperature during the preparation, resulting in a porous glass fiber having a smaller Young's modulus.

The following examples and comparative examples according to the invention relate to materials comprising:

(1) polycarbonate (C): bisphenol A polycarbonate with a melt index of 20g/10min at 300 ℃ under 1.2 kg;

(2) glass fiber:

alkali-free glass fibers, i.e. low-loss glass fibers, having a dielectric constant D at 5GHz _k Is 4.5, dielectric loss D _f Is 0.0032;

e-glass fiber, dielectric loss D at 1MHz _f 0.009, commercially available, 5GHz dielectric constant of 6, from self test, and dielectric loss of 0.035;

d-glass fiber, dielectric loss D at 1MHz _f 0.001, commercially available, 5GHz dielectric constant at self test, 0.02 dielectric loss;

the Young modulus of the reinforced glass fiber is 90GHz, the reinforced glass fiber is commercially available, the dielectric constant of 5GHz is 4.5 by self-inspection, and the dielectric loss is 0.006;

(3) a toughening agent: a commercially available maleic anhydride grafted ethylene-octene copolymer elastomer;

(4) coupling agent: gamma-aminopropyltrimethoxysilane;

(5) antioxidant: an antioxidant 168;

(6) lubricant: commercially available silicone oils.

Example 1

The glass fiber reinforced polycarbonate material comprises the following components in parts by weight:

the preparation method of the glass fiber reinforced polycarbonate material comprises the following steps: mixing the baked polycarbonate, the alkali-free glass fiber, the porous glass fiber G3, the toughening agent, the coupling agent, the antioxidant and the lubricant in a mixer according to the formula amount, wherein the mixing speed is 500rpm, and the mixing time is 10 min; the mixed materials were fed into a twin screw extruder, the temperatures in the zones being set as follows: the first zone temperature is 260 ℃, the second zone temperature is 270 ℃, the third zone temperature is 280 ℃, the fourth zone temperature is 280 ℃, the fifth zone temperature is 280 ℃, the sixth zone temperature is 280 ℃, the seventh zone temperature is 280 ℃, the eighth zone temperature is 275 ℃, the ninth zone temperature is 275 ℃, the tenth zone temperature is 275 ℃, the eleventh zone temperature is 270 ℃ and the screw rotation speed is 550rpm, and the glass fiber reinforced polycarbonate material is obtained after extrusion, cooling, drying and grain cutting.

The glass fiber reinforced polycarbonate material is subjected to the following performance tests:

(1) tensile property: the elongation at break (%) and tensile strength (MPa) of the material were tested according to the method in ISO 527-1;

(2) bending property: the flexural modulus (MPa) and flexural strength (MPa) of the material were tested according to the method in ISO 178;

(3) impact property: the materials were tested for ASTM 3.2mm notched Izod impact strength according to the method in ASTM D256-2010, with an ambient temperature of 23 ℃;

(4) melt index: the melt index at 300 ℃ and 1.2mm was measured according to the method in ISO 1183-1;

(5) dielectric properties: testing the dielectric constant D of the material at 5GHz according to the SPDR resonant cavity method _k And dielectric loss D _f (ii) a Specific test data are shown in table 2.

Examples 2 to 11, comparative examples 1 to 5

The components, the amounts (in parts) and the performance test data of the glass fiber reinforced polycarbonate material are shown in tables 2, 3 and 4 respectively.

TABLE 2

TABLE 3

In table 3, the porous glass fibers in examples 6 to 8 were porous glass fibers G3 (preparation example 3), and the porous glass fibers in example 9 were porous glass fibers G6 (preparation example 6); the porous glass fibers in examples 10 to 11 were porous glass fibers G8 (preparation example 8) and G9 (preparation example 9), respectively.

TABLE 4

As can be seen from the performance test data in tables 2, 3 and 4, compared with the comparative examples 1-5 containing only one glass fiber, the examples 1-9 of the present invention compound the alkali-free glass fiber with low dielectric loss with the porous glass fiber, and modify the polycarbonate with the composite glass fiber material, so that the glass fiber reinforced polycarbonate material has a tensile strength of 105-118MPa, a tensile elongation at break of 4.2-6%, a bending modulus of 5600-7800MPa, a bending strength of 170-193MPa, a notched Izod impact strength of 198-220J/m, high impact toughness, good mechanical properties, a melt index of 9.6-15g/10min at 300 ℃ and 1.2mm, a good processability, lower dielectric loss and dielectric constant, a dielectric constant of 2.9-3.25 at 5GHz, a dielectric loss of 20% glass fiber content of 0.0015-0.0042, has excellent comprehensive mechanical properties such as dielectric property, processability, toughness, strength, impact resistance and the like. Meanwhile, by combining the embodiments 1 to 5, the mechanical property and the dielectric property of the glass fiber reinforced polycarbonate material can be adjusted by adjusting the proportion of the alkali-free glass fiber with low dielectric loss and the porous glass fiber and the total content of the glass fiber in the material, and the adjusting of the adding proportion of the glass fiber can be widened to a wider rangeDevelopment of glass-fiber-surrounding reinforced materials. In addition, in order to obtain the glass fiber reinforced polycarbonate material with better performance, the pore diameter of the porous glass fiber is preferably 0.5-3 μm, and the specific surface area is 300-600m ² The reinforcing glass fiber is preferably obtained by sequentially carrying out acid solution treatment, acid salt solution treatment and high-temperature drying on the reinforcing glass fiber, so that the reinforcing glass fiber has a good pore structure and low dielectric loss characteristics; if the porous glass fiber is not prepared by the preferred method of the present invention (examples 10-11), the dielectric properties and mechanical properties of the glass fiber reinforced polycarbonate material are reduced.

The applicant states that the present invention is illustrated by the above examples to show a glass fiber reinforced polycarbonate material, a preparation method and applications thereof, but the present invention is not limited to the above examples, i.e. it does not mean that the present invention must be implemented by the above examples. It should be understood by those skilled in the art that any modification of the present invention, equivalent substitutions of the raw materials of the product of the present invention, addition of auxiliary components, selection of specific modes, etc., are within the scope and disclosure of the present invention.

Claims

1. The glass fiber reinforced polycarbonate material is characterized by comprising the following components in parts by weight:

40-95 parts of polycarbonate

1-40 parts of alkali-free glass fiber

1-40 parts of porous glass fiber;

2. The glass fiber reinforced polycarbonate material of claim 1, wherein the polycarbonate comprises bisphenol a polycarbonate;

preferably, the polycarbonate has a melt index at 300 ℃ under 1.2kg of 5 to 40g/10 min.

3. The glass fiber reinforced polycarbonate material of claim 1 or 2, wherein the alkali-free glass fibers comprise SiO ₂ The mass percentage content of the compound is more than or equal to 90 percent;

preferably, the alkali-free glass fiber has a dielectric loss of 0.0030 to 0.0035 at 5 GHz;

preferably, the alkali-free glass fiber has a dielectric constant of 4.2 to 4.8 at 5 GHz.

4. The glass fiber reinforced polycarbonate material of any one of claims 1-3, wherein the porous glass fiber has a pore size of 0.5-3 μm;

preferably, the specific surface area of the porous glass fiber is 300-600m ² /g；

Preferably, the dielectric loss of the porous glass fiber at 5GHz is 0.002-0.003;

preferably, the dielectric constant of the porous glass fiber at 5GHz is 3.7-4.2;

preferably, the mass ratio of the porous glass fiber to the alkali-free glass fiber is 1 (0.3-1.3);

preferably, the sum of the mass percent of the alkali-free glass fiber and the mass percent of the porous glass fiber in the glass fiber reinforced polycarbonate material is 5-50%.

5. The glass fiber reinforced polycarbonate material of any one of claims 1-4, wherein the porous glass fiber is obtained by pore-forming reinforced glass fiber in an acidic solution;

preferably, the young's modulus of the reinforced glass fiber is 50-90 GPa;

preferably, the strength ratio of the porous glass fiber to the reinforced glass fiber is (0.5-0.8): 1;

preferably, the porous glass fiber is prepared by a method comprising: sequentially treating the reinforced glass fiber in an acid solution and an alkaline salt solution, and drying to obtain the porous glass fiber;

preferably, the pH of the acid solution is 2-5;

preferably, the acid solution comprises any one of a hydrochloric acid solution, a sulfuric acid solution or a nitric acid solution or a combination of at least two of the two;

preferably, the treatment time in the acid solution is 1-8 h;

preferably, the treatment temperature in the acid solution is 30-80 ℃;

preferably, the treatment in the acid solution is carried out under stirring conditions;

preferably, the alkaline salt solution has a pH of 7.5 to 9;

preferably, the salt in the basic salt solution comprises an acid salt;

preferably, the acid salt comprises any one of sodium bicarbonate, potassium bicarbonate or sodium borate or a combination of at least two thereof;

preferably, the treatment time in the alkaline salt solution is 0.5-6 h;

preferably, the treatment temperature in the alkaline salt solution is 30-80 ℃;

preferably, the temperature of the drying is 400-700 ℃;

preferably, the drying time is 0.5-2 h.

6. The glass fiber reinforced polycarbonate material of any one of claims 1-5, further comprising 0.1-1 parts by weight of a toughening agent;

preferably, the toughening agent comprises any one of methyl methacrylate-butadiene-styrene copolymer, maleic anhydride grafted ethylene-octene copolymer elastomer, ethylene-butyl acrylate-glycidyl methacrylate copolymer, ethylene-methyl acrylate-glycidyl methacrylate copolymer or methyl methacrylate-styrene-organosilicon copolymer or a combination of at least two of the two;

preferably, the glass fiber reinforced polycarbonate material further comprises 0.3-10 parts by weight of a coupling agent;

preferably, the coupling agent comprises any one of or a combination of at least two of a silane coupling agent, a titanate coupling agent or an aluminate coupling agent;

preferably, the silane coupling agent comprises any one or a combination of at least two of gamma-aminopropyltrimethoxysilane, gamma-aminopropyltriethoxysilane, gamma-glycidoxypropyltrimethoxysilane or gamma-glycidoxypropyltriethoxysilane;

7. The glass fiber reinforced polycarbonate material of any one of claims 1-6, wherein the glass fiber reinforced polycarbonate material further comprises 0.01-5 parts by weight of an antioxidant;

preferably, the antioxidant comprises any one of hindered phenol antioxidant, hindered amine antioxidant, phosphite antioxidant or thioester antioxidant or a combination of at least two of the hindered phenol antioxidant, the hindered amine antioxidant and the thioester antioxidant;

preferably, the glass fiber reinforced polycarbonate material further comprises 0.01-5 parts by weight of a lubricant;

preferably, the lubricant comprises any one of pentaerythritol stearate, ethylene wax or silicone oil or a combination of at least two thereof.

8. A method for preparing a glass fiber reinforced polycarbonate material according to any of claims 1 to 7, wherein the method comprises: mixing polycarbonate, alkali-free glass fiber and porous glass fiber, and then melting and extruding to obtain the glass fiber reinforced polycarbonate material.

9. The method as claimed in claim 8, wherein the temperature of the melt extrusion is 240-290 ℃;

preferably, the melt extrusion is carried out in a screw extruder;

preferably, the screw rotating speed of the screw extruder is 350-750 rpm;

preferably, the mixed material further comprises any one of or a combination of at least two of a toughening agent, a coupling agent, an antioxidant or a lubricant.

10. Use of the glass fiber reinforced polycarbonate material according to any of claims 1 to 7 in a housing for communication equipment, automotive parts or electrical appliances.