阅读说明：本技术 一种用作热塑性树脂基复合材料增强体的高模量碳纤维及其制备方法 (A kind of high modulus carbon fiber and preparation method thereof as thermoplastic resin based composite material reinforcement ) 是由 张学军 董玉双 田艳红 郝瑞婷 于 2019-09-11 设计创作，主要内容包括：本发明涉及一种用作热塑性树脂复合材料增强体的高模量碳纤维及其制备方法,包括标准碳纤维产品的表面纯化、高模化、恒流电解氧化、上胶剂亚胺化等步骤。其中,标准模量碳纤维的表面纯化是在惰性气氛下脱除纤维表面的高分子物质,高模化是指温度超过2000℃的惰性气氛下热处理,恒流电解氧化是指纤维在铵盐电解质溶液中进行电化学氧化,上胶剂亚胺化是指纤维表面涂覆的热塑性树脂前驱体上胶剂经过热处理转变成聚酰亚胺类上胶剂。该方法制备出的碳纤维具有高模量,且与热塑性树脂基体的粘接性能得以显著提高,可作为热塑性树脂复合材料的增强体,适用于工业化生产。(The present invention relates to a kind of high modulus carbon fiber and preparation method thereof as thermoplas tic resin composite's reinforcement, surface purifying, high modelling, constant-current electrolysis oxidation, cementing agent imidization including standard carbon fiber product and etc..Wherein, the surface purifying of standard modulus carbon fiber is the polymer substance for removing fiber surface under an inert atmosphere; high modelling refers to that temperature is more than to be heat-treated under 2000 DEG C of inert atmosphere; constant-current electrolysis oxidation refers to that fiber carries out electrochemical oxidation in ammonium salt electrolyte solution, and cementing agent imidization refers to that the thermoplastic resin presoma cementing agent of fiber surface coating is transformed into polyimide cementing agent through Overheating Treatment.The carbon fiber that this method is prepared has high-modulus, and is significantly improved with the adhesive property of thermoplastic resin matrix, can be used as the reinforcement of thermoplas tic resin composite, is suitable for industrialized production.)

1. a kind of preparation method of the high-modules carbon fibre reinforcement as thermoplastic resin based composite material, which is characterized in that mark Quasi- carbon fiber product is prepared through the step of surface purifying, high modelling, constant-current electrolysis oxidation, cementing agent imidization.

2. preparation method according to claim 1, which comprises the following steps:

(1) standard carbon fiber surface purifies: providing a kind of carbon fiber of standard modulus, carries out at the purifying of surface to the carbon fiber Reason removes the polymer substance of fiber surface under an inert atmosphere；

(2) high modelling: the carbon fiber of the carry out surface purification process is subjected to superhigh temperature heat treatment in an inert atmosphere, makes carbon fiber Dimension crystallite is rearranged, is orientated, and obtains high modelling carbon fiber；

(3) constant-current electrolysis aoxidizes: the high modelling carbon fiber being carried out electrochemical oxidation in ammonium salt electrolyte solution, is obtained High-modules carbon fibre of the surface Jing Guo oxidation processes；

(4) cementing agent imidization: by the high-modules carbon fibre surface polyamide coating acid cementing agent by surface oxidation treatment, It is then heat-treated to obtain the high-modules carbon fibre reinforcement that surface is coated with polyimides sizing agent.

3. preparation method according to claim 2, which is characterized in that the high modulus carbon fiber refer to tensile modulus >= 350GPa, the carbon fiber of standard modulus refer to the carbon fiber of tensile modulus 220-250GPa.

4. preparation method according to claim 1 or 2, which is characterized in that the thermoplastic resin refer to polyimides, The thermostability engineering plastics such as polyether sulfone, polyether-ether-ketone.

5. preparation method according to claim 2, which is characterized in that in step (1), under an inert atmosphere in 300-500 The polymer substance of fiber surface is removed at DEG C；The inert atmosphere is preferably nitrogen atmosphere.

6. preparation method according to claim 2, which is characterized in that in step (2), temperature is more than 2000 DEG C of indifferent gas Hot gas spring is carried out under atmosphere to handle 1-3 minutes；The inert atmosphere is preferably nitrogen atmosphere.

7. preparation method according to claim 2, which is characterized in that in step (3), the high modelling carbon fiber is existed Electrochemical oxidation is carried out in organic and inorganic or both mixed-ammonium salt electrolyte solution, current density is 0.6-2 mA/cm², temperature Degree is 40-70 DEG C.

8. preparation method according to claim 2, which is characterized in that in step (4), the temperature of the heat treatment is 200℃。

9. what preparation method according to claim 1 to 8 was prepared is used as thermoplastic resin based composite material High-modules carbon fibre reinforcement.

Technical field

The invention belongs to carbon fibre material fields, and in particular to a kind of as thermoplastic resin based composite material reinforcement High modulus carbon fiber and preparation method thereof.

Background technique

In recent years, using general engineering plastic and high performance engineering plastics as the thermoplastic resin based composite material of matrix resin It is increasingly paid close attention to by people, and has become the research hotspot of field of compound material Showed Very Brisk.But due to high modulus carbon fiber Surface is smooth, chemical inertness is big, surface energy is low, it is difficult to generate effective interfacial bonding with thermoplastic resin and act on, cause compound Material interface properties are difficult to meet practical application request.Therefore it is necessary to carry out thermoplastic resin in high-modulus carbon fiber preparation process Aliphatic radical compatability technological design is prepared so as to improve the interface performance of composite material suitable for thermoplastic resin-based compound The high-modules carbon fibre of Material reinforcement body.

Currently, be improve carbon fiber and resin matrix interfacial adhesion and compatibility, common method have sizing agent method, Nanoparticle modified method, surface oxidation method, plasma processing method etc., wherein although plasma surface treatment can be effective Improve the interface performance of composite material, but require processing environment harsh, device complexity, higher cost, to continuous tow processing It is ineffective, limit the large-scale application of plasma method industrially.Generally speaking, at cementing agent method and surface oxidation method Reason method is simple, easy to implement, interface reinforcing effect is obvious, is the common method of industrial surface treatment of carbon fibers.

CN104894869A discloses a kind of fast preparation method of carbon fiber reinforcement.The preparation method has simple easy It goes and sizing agent used is modified by commercial epoxy resin emulsion type sizing agent to the undamaged advantage of fiber itself, but in the patent It is made, main slurry is epoxy resin, and heat resistance is poor, and the carbon fiber reinforcement of preparation is not suitable for thermoplastic resin matrix.

CN105542227A discloses a kind of carbon fiber reinforcement and preparation method thereof.The preparation method passes through silane, coupling Carbon fiber of the mixture with surface Jing Guo oxidation processes is reacted, and the carbon fiber that surface has silanol groups is obtained.It is mentioned in patent Silanol groups are had to due to prepared carbon fiber reinforcement surface, can be compound with various types of resins, but there is no should in patent Reinforcement is applied to the research in terms of thermoplastics type's epoxy resin-base composite material mechanical property.Above technology is without good Solve the problems, such as high-modules carbon fibre be used as thermoplastic epoxy based composites reinforcement when with matrix compatibility.

Summary of the invention

In order to solve the problems in the existing technology, provided by the invention a kind of as thermoplastic resin based composite material High-modules carbon fibre reinforcement and preparation method thereof, standard carbon fiber product through surface purifying, high modelling, constant-current electrolysis oxidation, The step of cementing agent imidization, is prepared.While assigning carbon fiber high-modulus, itself and thermoplastic resin matrix's are improved Cementability and compatibility, so that carbon fiber and the interface performance of thermoplastic resin matrix are improved.

More specifically, the preparation method the following steps are included:

(1) standard carbon fiber surface purifies: providing a kind of carbon fiber of standard modulus, carries out at the purifying of surface to the carbon fiber Reason removes the polymer substance of fiber surface under an inert atmosphere；

(2) high modelling: the carbon fiber of the carry out surface purification process is subjected to superhigh temperature heat treatment in an inert atmosphere, makes carbon fiber Dimension crystallite is rearranged, is orientated, and obtains high modelling carbon fiber；

(3) constant-current electrolysis aoxidizes: the high modelling carbon fiber being carried out electrochemical oxidation in ammonium salt electrolyte solution, is obtained High-modules carbon fibre of the surface Jing Guo oxidation processes；

(4) cementing agent imidization: by the high-modules carbon fibre surface polyamide coating acid cementing agent by surface oxidation treatment, It is then heat-treated to obtain the high-modules carbon fibre reinforcement that surface is coated with polyimides sizing agent.

In the preferred embodiments of the present invention, the high modulus carbon fiber refers to tensile modulus >=350GPa, mark The carbon fiber of quasi-mode amount refers to the carbon fiber of tensile modulus 220-250GPa.

In the preferred embodiments of the present invention, the thermoplastic resin refers to polyimides, polyether sulfone, polyethers ether The thermostability engineering plastics such as ketone.

In the preferred embodiments of the present invention, in step (1), removed at 300-500 DEG C under an inert atmosphere fine The polymer substance in dimension table face；The inert atmosphere is preferably nitrogen atmosphere.

In the preferred embodiments of the present invention, in step (2), temperature is more than that heat is carried out under 2000 DEG C of inert atmosphere Drawing-off is handled 1-3 minutes；The inert atmosphere is preferably nitrogen atmosphere.

In the preferred embodiments of the present invention, in step (3), by the high modelling carbon fiber organic and inorganic Or both electrochemical oxidation is carried out in mixed-ammonium salt electrolyte solution, current density is 0.6-2 mA/cm², temperature 40-70 ℃。

In the preferred embodiments of the present invention, in step (4), the temperature of the heat treatment is 200 DEG C.

What the another aspect of the present invention protection preparation method was prepared is used as thermoplastic resin based composite material High-modules carbon fibre reinforcement.

Compared with prior art, high-modules carbon fibre reinforcement and preparation method provided by the invention have the advantage that

First, by not surface treated high-modules carbon fibre use anode constant current oxidation technology, using high-modules carbon fibre as Working electrode, graphite are cathode, using ammonium salt as electrolyte, by control current density and temperature, to obtain being surface-treated most Excellent high-modules carbon fibre.The result shows that high-modules carbon fibre surface functional group content has obtained one after carrying out electrochemical oxidation The raising for determining degree increases the chemical reactivity of fiber surface, so that the carbon fiber surface has biggish active function Group can react to form chemical bond with the functional group of resin surface at interface, which is remarkably improved carbon fiber and tree Adhesive strength between rouge.

Second, by being obtained after heat treatment to the high-modules carbon fibre polyamide coating acid cementing agent Jing Guo surface oxidation treatment To polyimide cementing agent.The cementing agent has excellent heat resistance, and it is thermoplastic resin-based to can satisfy fibre reinforced The processing temperature requirement of composite material, so, it is suitable for thermoplastic resin-based composite wood by the way that the preparation method is available The high-modules carbon fibre reinforcement of material.

Third, polyimide cementing agent used by this preparation method are aqueous cementing agent, have environment friendly.

4th, the carbon fiber that preparation method of the invention is prepared has high-modulus, and viscous with thermoplastic resin matrix It connects performance to be significantly improved, can be used as the reinforcement of thermoplas tic resin composite, be suitable for industrialized production.

Specific embodiment

In order to make the objectives, technical solutions, and advantages of the present invention clearer, below in conjunction with specific embodiment, to this Invention is further elaborated.It should be appreciated that described herein, specific examples are only used to explain the present invention, without structure At limitation of the present invention.

Embodiment 1

(1) standard carbon fiber surface purifies

The surface purifying of standard modulus carbon fiber is the macromolecule of 400 DEG C of heat treatment, 3 minutes removing fiber surfaces under nitrogen atmosphere Substance.

(2) superhigh temperature is graphitized

Graphitization processing is carried out by graphitizing furnace is sent by the carbon fiber of surface purification process, is protection gas, nitrogen with nitrogen Middle oxygen content is 1.0ppm；Graphitization temperature is 2150 DEG C, and the residence time is 3 minutes.

(3) constant-current electrolysis aoxidizes

Current density is controlled using direct current/regulated power supply, high modelling carbon fiber is carried out in 5% ammonium hydrogen carbonate electrolyte solution Continuous constant current oxidation processing, current density are 1 mA/cm², 50 DEG C of operation temperature, then eluted with deionized water, remove surface Remaining electrolyte ion, drying.

(4) cementing agent imidization

Above-mentioned carbon fibre tow is sent into aqueous polyamide acid sizing agent and impregnates 35s, it is then dry in 200 DEG C of drying oven 10 minutes, the starching amount for obtaining carbon fiber was 0.4%.

After tested, the modulus 370GPa of the high-modules carbon fibre of method of the invention preparation, enhances polyether sulfone based composites Interlaminar shear strength be 54MPa.