阅读说明：本技术 一种MXene/聚酰胺酰亚胺复合上浆剂及其制备方法和应用 (MXene/polyamide imide composite sizing agent and preparation method and application thereof ) 是由 姜再兴 苑雪玉 董继东 郑文慧 纪媛 徐丽娟 李阳阳 高国林 李冰 刘丽 黄玉东 于 2020-07-27 设计创作，主要内容包括：一种MXene/聚酰胺酰亚胺复合上浆剂及其制备方法和应用,它涉及纤维上浆剂及其制备方法和应用。它是要解决现有的纤维上浆剂对复合材料的力学性能差的技术问题。本发明的上浆剂是由Ti<Sub>3</Sub>C<Sub>2</Sub>T<Sub>x</Sub> MXene分散液、分散剂溶液和聚酰胺酰亚胺溶液混合而成。制法：将Ti<Sub>3</Sub>C<Sub>2</Sub>T<Sub>x</Sub> MXene分散液、分散剂溶液和聚酰胺酰亚胺溶液混合即可。可将上浆剂作为热塑性复合材料增强纤维的处理剂,制备纤维增强热塑性复合材料的方法：将纤维脱浆、氧化后用MXene/聚酰胺酰亚胺复合上浆剂浸渍,然后分散到热塑性树脂中,成型,得到的复合材料的层间剪切强度达到55MPa～85MPa。可用于航空航天、汽车或工程等领域。(An MXene/polyamide imide composite sizing agent and a preparation method and application thereof relate to a fiber sizing agent and a preparation method and application thereof. The technical problem that the existing fiber sizing agent is poor in mechanical property of a composite material is solved. The sizing agent of the invention is prepared from Ti 3 C 2 T x MXene dispersion liquid, dispersant solution and polyamide-imide solution. The preparation method comprises the following steps: mixing Ti 3 C 2 T x Mixing MXene dispersion liquid, dispersant solution and polyamide-imide solution. The sizing agent can be used as a treating agent for reinforced fibers of the thermoplastic composite material, and the method for preparing the fiber reinforced thermoplastic composite material comprises the following steps: desizing and oxidizing the fiber, then impregnating the fiber with MXene/polyamide imide composite sizing agent, dispersing the fiber into thermoplastic resin, and molding to obtain the composite material with the interlaminar shear strength of 55-85 MPa. Can be used in the fields of aerospace, automobiles or engineering and the like.)

1. An MXene/polyamide imide composite sizing agent is characterized in that the composite sizing agent is prepared from 1-10% of Ti by mass₃C₂T_xThe composite material is prepared by mixing MXene dispersion liquid, 0.04-10.00% of dispersant and 0.1-10.0% of polyamide-imide solution according to the mass ratio of (5-5.5) to 1 (4-4.5).

2. The MXene/polyamideimide composite sizing agent according to claim 1, wherein the dispersant is triethylhexylphosphoric acid, sodium dodecylsulfate or methylpentanol.

3. The MXene/polyamideimide composite sizing agent according to claim 1 or 2, characterized in that the polyamideimide is a polyamideimide having an amine group and/or a carboxyl group.

4. The MXene/polyamideimide composite sizing agent according to claim 1 or 2, wherein the solvent in the polyamideimide solution is deionized water, chloroform, ethanol or N-methylpyrrolidone.

5. The method for preparing the MXene/polyamide imide composite sizing agent of claim 1, which is characterized by comprising the following steps:

firstly, preparing Ti₃C₂T_xMXene dispersion liquid;

secondly, adding polyamide-imide (PAI) into a solvent for dissolving according to the mass percentage concentration of 0.1-10.0% of PAI to obtain a polyamide-imide solution;

thirdly, weighing Ti with the mass percentage concentration of 1-10 percent according to the mass ratio of (5-5.5) to (1) (4-4.5)₃C₂T_xMXene dispersion liquid, dispersant with the mass percentage concentration of 0.04-10.00 percent and polyamide-imide solution with the mass percentage concentration of 0.1-10.0 percent; firstly, adding a dispersing agent into Ti₃C₂T_xUniformly stirring the MXene dispersion liquid to obtain Ti₃C₂T_XMXene dispersant solution, and adding polyamide imide solution to Ti₃C₂And (3) carrying out ultrasonic treatment on the MXene dispersant solution for 5-30 min, and then continuously stirring for 10-20 min at the temperature of 15-30 ℃ to obtain the MXene/polyamide imide composite sizing agent.

6. The method for preparing MXene/polyamideimide composite sizing agent according to claim 5, wherein in the step one, Ti₃C₂T_xThe preparation method of the MXene dispersion liquid comprises the following steps:

a. adding 9M hydrochloric acid and LiF into a plastic container, and uniformly mixing to obtain a mixed solution; wherein the ratio of the volume of the 9M hydrochloric acid to the mass of LiF is (12-15) mL: 1g of a compound;

b. adding Ti to the mixed solution₃AlC₂Magnetically stirring the powder for 48 to 50 hours at the temperature of 50 to 55 ℃ to obtain an etching product, namely a multilayer Ti₃C₂T_xMXene, then multiple layers of Ti₃C₂T_xLayering MXene by ultrasonic degradation method to obtain layered Ti₃C₂T_xMXene; wherein Ti₃AlC₂The ratio of the mass of the powder to the volume of the mixed solution is 1 g: (10-20) mL;

c. the layered product Ti₃C₂T_xMXene was washed with deionized water to pH>5, then centrifugally separating to obtain delaminated Ti₃C₂T_xNanosheets;

d. ti to be delaminated₃C₂T_xDispersing the nanosheets in distilled water, carrying out ultrasonic treatment for 1.5-2 h in an argon atmosphere, then carrying out centrifugal treatment for 1-1.5 h at a rotating speed of 3500-6000 rpm, and collecting supernatant, namely Ti₃C₂T_xMXene dispersion, Ti in supernatant₃C₂T_xThe mass percentage concentration of MXene is 1-10%.

7. The use of MXene/polyamideimide composite sizing agent according to claim 1, wherein the composite sizing agent is used as a treating agent for thermoplastic composite reinforcing fiber.

8. The use of MXene/polyamideimide composite sizing agent according to claim 7, wherein the method for preparing thermoplastic composite material using MXene/polyamideimide composite sizing agent comprises the following steps:

firstly, putting the fiber into a desizing solvent, and carrying out reflux treatment for 40-50 hours at the temperature of 60-80 ℃; then taking out the fiber, putting the fiber into an oxidant with the mass percentage concentration of 5-50%, and stirring for 0.5-1 hour at the temperature of 60-90 ℃; finally, taking out the fiber, washing with water, and drying to obtain oxidized fiber;

secondly, soaking the oxidized fiber into MXene/polyamide imide composite sizing agent for 5-30 min, then washing the oxidized fiber with deionized water, and drying the oxidized fiber in vacuum to obtain the fiber coated with the polyamide imide and the MXene;

and thirdly, dispersing the fiber coated with the polyamide imide and the MXene into thermoplastic resin according to the mass percent of the fiber coated with the polyamide imide and the MXene of 50-55%, and molding to obtain the fiber reinforced thermoplastic composite material.

9. The use of an MXene/polyamideimide composite sizing agent according to claim 8, wherein the fiber in the first step is a carbon fiber, a glass fiber or an aramid fiber.

10. The use of an MXene/polyamideimide composite sizing agent according to claim 8 or 9, wherein the desizing solvent in the first step is acetone, ethanol or tetrahydrofuran.

Technical Field

The invention relates to a preparation method of a fiber sizing agent.

Background

With the development of aerospace, military and automobile industries, the demand and the use amount of fiber reinforced resin matrix composite materials are increasing dramatically, and the use amount of the fiber reinforced resin matrix composite materials on automobiles and large-sized airplanes becomes one of important indexes for measuring the advancement of automobile and airplane structures. The matrix of the fiber reinforced resin matrix composite material can be thermosetting resin or thermoplastic resin, wherein the fiber reinforced thermoplastic resin composite material taking the thermoplastic resin as the matrix has the characteristics of light weight, designability of an integral structure, reusability, high forming speed, corrosion resistance, high damage tolerance and the like, is mainly applied to the field of aerospace, and is widely applied to the fields of automobiles, engineering and the like in recent years. However, in the application, the surface of the fiber is inert and nonpolar, lacks active functional groups, and the thermoplastic resin is generally polar, has high melting point and high melt viscosity, so that the interface performance of the fiber reinforced thermoplastic resin composite material is poor, the mechanical property of the composite material is limited to be improved, and the application of the fiber reinforced thermoplastic resin composite material is limited. In order to improve the poor interfacial properties of fiber reinforced thermoplastic resin composites, sizing agents are generally applied to the fiber surface. A master thesis of the university of harbin in 2011, namely 'process research on a carbon fiber surface high-temperature-resistant sizing agent and effect evaluation thereof' discloses a sizing agent for carbon fibers, wherein polyamideimide with the mass fraction of 0.1% is used as the sizing agent for the carbon fibers, the monofilament composite material formed by the sizing fibers and epoxy resin and bismaleimide resin has good temperature resistance and good moisture-heat resistance, the tensile strength of the sized carbon fibers is improved by 13.3% only compared with that of bare fibers, and the mechanical property of the composite material is not greatly improved.

Disclosure of Invention

The invention provides an MXene/polyamide-imide composite sizing agent and a preparation method and application thereof, aiming at solving the technical problem that the mechanical property of the existing fiber sizing agent to a composite material is poor.

The MXene/polyamide imide composite sizing agent of the inventionIs prepared from 1-10 wt% of Ti₃C₂T_xThe composite material is prepared by mixing MXene dispersion liquid, 0.04-10.00% of dispersant and 0.1-10.0% of polyamide-imide solution according to the mass ratio of (5-5.5) to 1 (4-4.5).

Further, the dispersant is triethylhexylphosphoric acid, sodium dodecyl sulfate or methylpentanol;

still further, the polyamideimide is a polyamideimide having an amine group and/or a carboxyl group;

further, the solvent in the polyamideimide solution is deionized water, chloroform, ethanol or N-methylpyrrolidone.

The preparation method of the MXene/polyamide imide composite sizing agent comprises the following steps:

firstly, preparing Ti₃C₂T_xMXene dispersion liquid;

secondly, adding polyamide-imide (PAI) into a solvent for dissolving according to the mass percentage concentration of 0.1-10.0% of PAI to obtain a polyamide-imide solution;

thirdly, weighing Ti with the mass percentage concentration of 1-10 percent according to the mass ratio of (5-5.5) to (1) (4-4.5)₃C₂T_xMXene dispersion liquid, dispersant with the mass percentage concentration of 0.04-10.00 percent and polyamide-imide solution with the mass percentage concentration of 0.1-10.0 percent; firstly, adding a dispersing agent into Ti₃C₂T_xUniformly stirring the MXene dispersion liquid to obtain Ti₃C₂T_XMXene dispersant solution, and adding polyamide imide solution to Ti₃C₂And (3) carrying out ultrasonic treatment on the MXene dispersant solution for 5-30 min, and then continuously stirring for 10-20 min at the temperature of 15-30 ℃ to obtain the MXene/polyamide imide composite sizing agent.

Further, in step one, Ti₃C₂T_xThe preparation method of the MXene dispersion liquid comprises the following steps:

a. adding 9M hydrochloric acid and LiF into a plastic container, and uniformly mixing to obtain a mixed solution; wherein the ratio of the volume of the 9M hydrochloric acid to the mass of LiF is (12-15) mL: 1g of a compound;

b. adding Ti to the mixed solution₃AlC₂Magnetically stirring the powder for 48 to 50 hours at the temperature of 50 to 55 ℃ to obtain an etching product, namely a multilayer Ti₃C₂T_xMXene, then multiple layers of Ti₃C₂T_xLayering MXene by ultrasonic degradation method to obtain layered Ti₃C₂T_xMXene; wherein Ti₃AlC₂The ratio of the mass of the powder to the volume of the mixed solution is 1 g: (10-20) mL;

c. the layered product Ti₃C₂T_xMXene was washed with deionized water to pH>5, then centrifugally separating to obtain delaminated Ti₃C₂T_xNanosheets;

d. ti to be delaminated₃C₂T_xDispersing the nanosheets in distilled water, carrying out ultrasonic treatment for 1.5-2 h in an argon atmosphere, then carrying out centrifugal treatment for 1-1.5 h at a rotating speed of 3500-6000 rpm, and collecting supernatant, namely Ti₃C₂T_xMXene dispersion, Ti in supernatant₃C₂T_xThe mass percentage concentration of MXene is 1-10%.

Further, in the second step, the polyamide imide is polyamide imide with amino or carboxyl;

furthermore, in the second step, the solvent is deionized water, chloroform, ethanol or N-methylpyrrolidone;

further, the dispersant in the third step is triethyl hexyl phosphoric acid, sodium dodecyl sulfate or methyl amyl alcohol;

the MXene/polyamide imide composite sizing agent is applied as a treating agent for thermoplastic composite reinforcing fibers.

The method for preparing the fiber reinforced thermoplastic composite material by using the MXene/polyamide imide composite sizing agent comprises the following steps:

firstly, putting the fiber into a desizing solvent, and carrying out reflux treatment for 40-50 hours at the temperature of 60-80 ℃; then taking out the fiber, putting the fiber into an oxidant with the mass percentage concentration of 5-50%, and stirring for 0.5-1 hour at the temperature of 60-90 ℃; finally, taking out the fiber, washing with water, and drying to obtain oxidized fiber;

secondly, soaking the oxidized fiber into MXene/polyamide imide composite sizing agent for 5-30 min, then washing the oxidized fiber with deionized water, and drying the oxidized fiber in vacuum to obtain the fiber coated with the polyamide imide and the MXene;

and thirdly, dispersing the fiber coated with the polyamide imide and the MXene into thermoplastic resin according to the mass percent of the fiber coated with the polyamide imide and the MXene of 50-55%, and molding to obtain the fiber reinforced thermoplastic composite material.

Furthermore, the fiber in the step one is carbon fiber, glass fiber or aramid fiber;

further, the desizing solvent in the step one is acetone, ethanol or Tetrahydrofuran (THF);

furthermore, the oxidant in the step one is potassium permanganate, concentrated nitric acid with the mass percentage concentration of 65-68%, concentrated sulfuric acid with the mass percentage concentration of 96-98%, manganese dioxide or hydrogen peroxide;

furthermore, the temperature of the vacuum drying in the step two is 40-60 ℃, and the drying time is 10-12 hours;

the sizing agent of the present invention contains Ti₃C₂T_xMXene and polyamide imide, desizing the fiber, oxidizing, dipping into sizing agent, forming hydrogen bond with carboxyl, hydroxyl on the fiber and amido bond and imide bond on polyamide imide through hydroxyl, fluorinion, oxygen anion and the like on MXene, simultaneously, MXene can also improve the roughness of the fiber, nano-component MXene is also beneficial to better interaction of the interface, in addition, the thermoplastic polyamide imide has good compatibility with the thermoplastic resin, and the factors improve the interface bonding force of the fiber and the thermoplastic resin. The interlaminar shear strength of the reinforced thermoplastic composite material prepared by the fibers treated by the sizing agent reaches55 to 85MPa which is 1.5 to 2 times of that of the untreated polyamide-imide resin and 1 to 1.5 times of that of the polyamide-imide resin treated only by the polyamide-imide solution.

The fiber reinforced thermoplastic composite material can be used in the fields of aerospace, automobiles or engineering and the like.

Drawings

FIG. 1 is a scanning electron micrograph of fibers of untreated T300 fiber cloth of example 1;

FIG. 2 is a scanning electron micrograph of fibers of the oxidized fiber cloth of example 1;

FIG. 3 is a scanning electron microscope photograph of the fiber cloth coated with MXene and polyamideimide mixed sizing agent of example 1;

FIG. 4 is a graph comparing the surface energy of untreated T300, desized T300, oxidized T300, and sized T300;

FIG. 5 is a graph comparing interlaminar shear strength of untreated T300, desized T300, oxidized T300, and sized T300, respectively, with thermoplastic resin molded composites;

FIG. 6 is a scanning electron micrograph of fibers of the fiber cloth coated with the sizing agent of example 2.

Detailed Description

The following examples are used to demonstrate the beneficial effects of the present invention.