阅读说明：本技术 一种碳纤维用水性聚醚砜上浆剂及其制备方法 (Water-based polyether sulfone sizing agent for carbon fibers and preparation method thereof ) 是由 刘浏 敖玉辉 庄海林 尚垒 鄢飞 杜巍峰 李峥 于 2019-11-20 设计创作，主要内容包括：本发明提供一种碳纤维用水性聚醚砜上浆剂及其制备方法,属于上浆剂技术领域。该上浆剂,按照重量份数计,包括：聚醚砜树脂0.5-3份,改性纳米碳材料0.1-1份,表面活性剂0.2-2份,流平剂0.1-0.5份,润滑剂0.1-0.7份,粘合剂0.1-1份,抗静电剂0.2-0.8份,去离子水91-98.7份；所述的改性纳米碳材料为改性氧化石墨烯或改性碳纳米管。本发明还提供一种碳纤维用水性聚醚砜上浆剂的制备方法。本发明改性纳米碳与树脂结构相似,氨基官能团还能与聚醚砜树脂中的醚键和砜键形成氢键作用,进而保证上浆剂与树脂间具有良好的相容性以及优异的界面结合强度,显著提高了碳纤维增强聚醚砜复合材料的界面性能。(The invention provides a water-based polyether sulfone sizing agent for carbon fibers and a preparation method thereof, belonging to the technical field of sizing agents. The sizing agent comprises the following components in parts by weight: 0.5-3 parts of polyether sulfone resin, 0.1-1 part of modified nano carbon material, 0.2-2 parts of surfactant, 0.1-0.5 part of flatting agent, 0.1-0.7 part of lubricant, 0.1-1 part of adhesive, 0.2-0.8 part of antistatic agent and 91-98.7 parts of deionized water; the modified nano carbon material is modified graphene oxide or a modified carbon nano tube. The invention also provides a preparation method of the water-based polyether sulfone sizing agent for the carbon fiber. The modified nanocarbon has a similar structure to that of resin, and the amino functional group can form a hydrogen bond with ether bonds and sulfone bonds in the polyether sulfone resin, so that good compatibility and excellent interface bonding strength between the sizing agent and the resin are ensured, and the interface performance of the carbon fiber reinforced polyether sulfone composite material is remarkably improved.)

1. The water-based polyether sulfone sizing agent for the carbon fiber is characterized by comprising the following components in parts by weight:

0.5-3 parts of polyether sulfone resin, 0.1-1 part of modified nano carbon material, 0.2-2 parts of surfactant, 0.1-0.5 part of flatting agent, 0.1-0.7 part of lubricant, 0.1-1 part of adhesive, 0.2-0.8 part of antistatic agent and 91-98.7 parts of deionized water;

the modified nano carbon material is modified graphene oxide or a modified carbon nano tube.

2. The aqueous polyethersulfone sizing agent for carbon fibers as claimed in claim 1, wherein said modified graphene oxide or modified carbon nanotubes are obtained by modifying 4,4 '-diaminodiphenyl sulfone, 3',4,4 '-tetraaminodiphenyl sulfone, 4,4' -diaminodiphenyl ether, 3, 4-diaminodiphenyl ether, 2 '-diaminodiphenyl ether or 3,4,4' -triaminodiphenyl ether.

3. The aqueous polyethersulfone sizing agent as claimed in claim 1, wherein said surfactant is one or more of sodium dodecyl sulfate, benzalkonium chloride, tween-20, tween-40, tween-60, tween-80, polyoxyethylene monooleate, polyoxyethylene monolaurate, sodium oleate, potassium oleate, peregal O series, and OP series.

4. The aqueous polyethersulfone sizing agent for carbon fibers as claimed in claim 1, wherein the leveling agent is one or more of hydroxymethyl cellulose, polydimethylsiloxane, polymethylphenylsiloxane and acrylic resin.

5. The aqueous polyethersulfone sizing agent for carbon fibers as claimed in claim 1, wherein said lubricant is one or more selected from propylene glycol, glycerin, sorbitan monoesters, polyoxyethylene sorbitan esters, polyoxyethylene ethers and butyl stearates.

6. The aqueous polyethersulfone sizing agent for carbon fibers as claimed in claim 1, wherein said binder is one or more selected from carboxymethyl cellulose, hydroxyethyl cellulose, polyvinyl alcohol, acrylate, polyacrylamide and sodium polyacrylate.

7. The aqueous polyethersulfone sizing agent for carbon fibers as claimed in claim 1, wherein said antistatic agent is one or more selected from polyetheresteramide, polyetheresteracetamide, polyethylene oxide, propylene oxide copolymer and polyethylene glycol bismaleic acid monoester.

8. The preparation method of the aqueous polyethersulfone sizing agent for carbon fibers, as claimed in claim 1, is characterized by comprising the following steps:

the method comprises the following steps: dissolving polyether sulfone resin in an organic solvent, and fully stirring to completely dissolve the polyether sulfone resin to form a uniform resin solution;

step two: adding a surfactant into deionized water, stirring at a high speed for 30-60 min at 40-60 ℃ by using a high-speed shearing emulsifying stirrer, and cooling to room temperature to obtain a solution;

step three: slowly dripping the uniform resin solution obtained in the step one into the solution obtained in the step two under high-speed stirring to obtain a mixed solution;

step four: and (3) adding the modified nano carbon material into the mixed solution obtained in the third step, adding a flatting agent, a lubricating agent, an adhesive and an antistatic agent, and stirring at a high speed for 30-60 min at a constant shearing rate. And then removing the organic solvent to obtain the aqueous polyether sulfone sizing agent for the carbon fiber.

9. The method for preparing the sizing agent of the aqueous polyethersulfone for the carbon fibers in the step one of claim 8, wherein the organic solvent in the step one is one of dichloromethane or trichloromethane.

Technical Field

The invention belongs to the technical field of sizing agents, and particularly relates to a water-based polyether sulfone sizing agent for carbon fibers and a preparation method thereof.

Background

The carbon fiber as a high-performance fiber has a series of advantages of high specific strength, high specific modulus, fatigue resistance, low thermal expansion coefficient and the like, and is widely applied to the fields of aerospace, national defense and military industry and the like at present. However, after the carbon fiber is carbonized at high temperature, the surface active functional groups are less. Untreated carbon fibers have low surface energy, are chemically inert, have poor wettability with resin, and result in weak interfacial bonding force of the composite material. In addition, the carbon fiber has the characteristics of low elongation at break and high brittleness, and during production and manufacturing, after the fiber is rubbed, fluffing and breaking phenomena are easy to occur, so that the strength of the carbon fiber is reduced.

The sizing technique is an effective means for solving the above problems. On one hand, the surface of the carbon fiber is coated with a layer of sizing agent, so that the friction among the carbon fibers can be reduced, and the bundling effect is achieved; on the other hand, after sizing modification, a proper interface layer can be introduced between the carbon fiber and the matrix resin, so that the matrix resin and the fiber are well combined, and the interface performance of the composite material is improved. However, most of the sizing agents used by carbon fiber manufacturing enterprises at present are thermosetting sizing agents. The thermosetting sizing agent has relatively poor thermal stability, and is easy to decompose when the processing temperature of the composite material exceeds 250 ℃, so that the composite material generates holes and defects, the interface bonding strength is reduced, and the mechanical property of the composite material is influenced. In addition, thermosetting sizing agents are generally poorly compatible with thermoplastic resins. Therefore, the development of the thermoplastic sizing agent matched with different thermoplastic resins has important research significance. In general, sizing agents can be classified into three types, i.e., solvent type, emulsion type and aqueous type. Because the organic solvent in the solvent-based sizing agent is inflammable and can cause environmental pollution, the solvent-based sizing agent is not widely used any more, and most of carbon fiber production enterprises adopt emulsion-type sizing agents at present. In order to meet the increasingly stringent environmental regulations, developed countries have vigorously developed and developed aqueous solventless sizing agents. Therefore, the water-based sizing agent becomes a pet of the industry, and the development of the environment-friendly sizing agent meeting the three requirements of environmental protection, health and safety becomes an important research direction in the field of sizing agents.

In addition, GO and CNT have been widely used as a nanocarbon material excellent in performance for a composite reinforcement. The carbon fiber is introduced into a sizing agent and then modified to the surface of the carbon fiber by a sizing method, so that the interface performance between the carbon fiber and matrix resin is improved, and the purpose of further improving the macroscopic performance of the composite material is achieved. Therefore, the development of the aqueous thermoplastic sizing agent containing the nano-carbon material has important significance for the development of the carbon fiber industry.

In recent years, some studies have been made on sizing agents for sizing materials mainly composed of polyether sulfone resins. Patent CN 103757928A discloses a polyethersulfone aqueous sizing agent for improving the interface bonding strength between polyethersulfone resin and carbon fiber. However, part of the organic solvent (1.3% to 6.0%) is still present in the sizing system. Patent CN 104018355A discloses a sizing agent with sulfonic polyether sulfone as a main component, which not only improves the interface performance of carbon fiber reinforced polyether sulfone composite materials, but also gives full play to the advantages of high specific strength of carbon fiber and high temperature resistance of polyether sulfone. However, strong acid (98% concentrated sulfuric acid, chlorosulfonic acid, or fuming sulfuric acid) is added when the polyethersulfone resin is modified, and the organic solvent used for dissolving the polyethersulfone resin is not removed, which easily causes environmental pollution. Patent CN 106120345 a discloses a method for preparing a carbon fiber sizing agent, which comprises sulfonating, fermenting and distilling polyethersulfone resin to obtain a solid, and reacting the solid with acrylic acid to obtain a final sizing agent. However, the sizing agent is complicated in preparation process, more in working procedures and not beneficial to industrialization. In conclusion, it is necessary to research a water-based thermoplastic sizing agent which has simple preparation process, high temperature resistance, environmental friendliness and suitability for industrialization.

Disclosure of Invention

The invention aims to solve the problem that the existing thermosetting sizing agent has poor heat resistance and compatibility in a thermoplastic resin system, and provides a water-based polyether sulfone sizing agent for carbon fibers and a preparation method thereof.

The invention firstly provides a water-based polyether sulfone sizing agent for carbon fibers, which comprises the following components in parts by weight:

0.5-3 parts of polyether sulfone resin, 0.1-1 part of modified nano carbon material, 0.2-2 parts of surfactant, 0.1-0.5 part of flatting agent, 0.1-0.7 part of lubricant, 0.1-1 part of adhesive, 0.2-0.8 part of antistatic agent and 91-98.7 parts of deionized water;

the modified nano carbon material is modified graphene oxide or a modified carbon nano tube.

Preferably, the modified graphene oxide or the modified carbon nanotube is obtained by modifying 4,4 '-diaminodiphenyl sulfone, 3',4,4 '-tetraaminodiphenyl sulfone, 4,4' -diaminodiphenyl ether, 3, 4-diaminodiphenyl ether, 2 '-diaminodiphenyl ether or 3,4,4' -triaminodiphenyl ether.

Preferably, the surfactant is one or more of sodium dodecyl sulfate, benzalkonium chloride, tween series (tween-20, tween-40, tween-60, tween-80), polyoxyethylene monooleate, polyoxyethylene monolaurate, sodium oleate, potassium oleate, peregal O series and OP series.

Preferably, the leveling agent is one or more of hydroxymethyl cellulose, polydimethylsiloxane, polymethylphenylsiloxane and acrylic resin.

Preferably, the lubricant is one or more of propylene glycol, glycerol, sorbitan monoester, polyoxyethylene sorbitan ester, polyoxyethylene ether and butyl stearate.

Preferably, the adhesive is one or more of carboxymethyl cellulose, hydroxyethyl cellulose, polyvinyl alcohol, acrylate, polyacrylamide and sodium polyacrylate.

Preferably, the antistatic agent is one or more of polyether ester amide, polyether ester acetamide, polyethylene oxide, propylene oxide copolymer and polyethylene glycol dimaleate monoester.

The invention also provides a preparation method of the water-based polyether sulfone sizing agent for carbon fibers, which comprises the following steps:

the method comprises the following steps: dissolving polyether sulfone resin in an organic solvent, and fully stirring to completely dissolve the polyether sulfone resin to form a uniform resin solution;

step two: adding a surfactant into deionized water, stirring at a high speed for 30-60 min at 40-60 ℃ by using a high-speed shearing emulsifying stirrer, and cooling to room temperature to obtain a solution;

step three: slowly dripping the uniform resin solution obtained in the step one into the solution obtained in the step two under high-speed stirring to obtain a mixed solution;

step four: and (3) adding the modified nano carbon material into the mixed solution obtained in the third step, adding a flatting agent, a lubricating agent, an adhesive and an antistatic agent, and stirring at a high speed for 30-60 min at a constant shearing rate. And then removing the organic solvent to obtain the aqueous polyether sulfone sizing agent for the carbon fiber.

Preferably, the organic solvent in the first step is one of dichloromethane or trichloromethane.

The invention has the advantages of

The invention provides a water-based polyether sulfone sizing agent for carbon fibers and a preparation method thereof, wherein the main component of the sizing agent is the same as the structure of resin, the sizing agent and the resin have good compatibility, molecular chains can be intertwined and diffused in the preparation process of a composite material, and the intermolecular interaction force is improved; meanwhile, the sizing agent contains modified nano carbon materials GO or CNT. Firstly, the nano carbon material can effectively improve the specific surface area, the roughness and the surface energy of the carbon fiber and promote the mechanical meshing action between the fiber and the resin. Furthermore, the nanocarbon material modified with an amino compound having a structure similar to that of a resin not only has a structure similar to or the same as that of a resin, but also contains an amino functional group. On one hand, the modified nano carbon material has stronger binding power with matrix resin and can be uniformly dispersed in a sizing agent; on the other hand, the amino functional group can form a hydrogen bond with the oxygen-containing functional group in the resin, so that the molecular level contact of the carbon fiber and the resin at the interface is further improved, and the interface bonding strength of the composite material is enhanced.

The polyether sulfone water-based sizing agent provided by the invention is simple and reliable in preparation process, easy to repeatedly realize, environment-friendly and good in industrialization prospect.

Drawings

FIG. 1 is a scanning electron micrograph of sized carbon fibers and unsized carbon fibers obtained in example 1 of the present invention;

FIG. 2 is a graph of the thermal weight loss of sized carbon fibers obtained in example 1 of the present invention versus sized carbon fibers obtained in comparative examples 1 and 2;

FIG. 3 is a graph showing the results of interlaminar shear strength tests of the composite obtained in example 1 of the present invention and the composites obtained in comparative examples 1 and 2.

Detailed Description

The invention firstly provides a water-based polyether sulfone sizing agent for carbon fibers, which comprises the following components in parts by weight:

0.5-3 parts of polyether sulfone resin, 0.1-1 part of modified nano carbon material, 0.2-2 parts of surfactant, 0.1-0.5 part of flatting agent, 0.1-0.7 part of lubricant, 0.1-1 part of adhesive, 0.2-0.8 part of antistatic agent and 91-98.7 parts of deionized water;

the modified nano carbon material is modified graphene oxide or a modified carbon nano tube.

According to the present invention, the modified graphene oxide or the modified carbon nanotube is modified by a modifier, and the modifier is preferably 4,4 '-diaminodiphenyl sulfone, 3',4,4 '-tetraaminodiphenyl sulfone, 4,4' -diaminodiphenyl ether, 3, 4-diaminodiphenyl ether, 2 '-diaminodiphenyl ether, or 3,4,4' -triaminodiphenyl ether. The specific modification method preferably comprises:

firstly, 0.05-0.1 g of Graphene Oxide (GO) or carboxylated Carbon Nanotubes (CNT) and 1-2 g of a modifier are added into DMF, 5g of dehydrating agent dicyclohexylcarbodiimide and 0.8g of catalyst 4-dimethylaminopyridine are added, the mixture is continuously stirred and reacted for 24 hours at 40-60 ℃ to enable amino functional groups in amino compounds to react with carboxyl functional groups in GO or CNT, then the reacted mixture is subjected to centrifugal treatment for three times, the DMF is used for washing to remove unreacted dicyclohexylcarbodiimide and 4-dimethylaminopyridine, and finally the modified GO or CNT is obtained by vacuum drying at 60-80 ℃.

According to the invention, the surfactant is preferably one or more of sodium dodecyl sulfate, benzalkonium chloride, Tween series (Tween-20, Tween-40, Tween-60 and Tween-80), polyoxyethylene monooleate, polyoxyethylene monolaurate, sodium oleate, potassium oleate, peregal O series and OP series.

According to the invention, the leveling agent is preferably one or more of hydroxymethyl cellulose, polydimethylsiloxane, polymethylphenylsiloxane and acrylic resin.

According to the invention, the lubricant is preferably one or more of propylene glycol, glycerin, sorbitan monoester, polyoxyethylene sorbitan ester, polyoxyethylene ether and butyl stearate.

According to the invention, the adhesive is preferably one or more of carboxymethyl cellulose, hydroxyethyl cellulose, polyvinyl alcohol, acrylate, polyacrylamide and sodium polyacrylate.

According to the invention, the antistatic agent is preferably one or more of polyether ester amide, polyether ester acetamide, polyethylene oxide, propylene oxide copolymer and polyethylene glycol dimaleate monoester.

The invention also provides a preparation method of the water-based polyether sulfone sizing agent for carbon fibers, which comprises the following steps:

the method comprises the following steps: dissolving polyether sulfone resin in an organic solvent, and fully stirring to completely dissolve the polyether sulfone resin to form a uniform resin solution; the organic solvent is preferably one of dichloromethane or trichloromethane;

step two: adding a surfactant into deionized water, stirring at a high speed of 8000-12000 rpm for 30-60 min at 40-60 ℃ by using a high-speed shearing emulsifying stirrer, and cooling to room temperature to obtain a solution;

step three: slowly dripping the uniform resin solution obtained in the step one into the solution obtained in the step two under high-speed stirring to obtain a mixed solution;

step four: and (3) adding the modified nano carbon material into the mixed solution obtained in the third step, adding a leveling agent, a lubricant, an adhesive and an antistatic agent, and stirring at a high speed for 30-60 min at a constant shearing rate, wherein the preferred speed is 8000-12000 rpm. And then removing the organic solvent to obtain the aqueous polyether sulfone sizing agent for the carbon fiber.

According to the invention, the method for removing the organic solvent in the fourth step is reduced pressure distillation or stirring overnight at the rotating speed of 800-1500 rpm so as to completely volatilize the organic solvent.

According to the invention, the sizing agent prepared by the invention is used for treating carbon fibers, and the treatment method preferably comprises the following steps:

and (2) dipping and running the carbon fibers in a sizing agent for 5-30 s at a drying temperature of 100-120 ℃, and drying the carbon fibers to obtain the carbon fiber reinforced polyether sulfone composite material through a resin solution dipping process and a hot press molding process.

The present invention will be described in further detail with reference to examples. The examples are intended to illustrate the invention only and do not limit the scope of the invention. Various changes or modifications may be made by one skilled in the art after reading the disclosure of the present invention, and such equivalents are intended to fall within the scope of the appended claims.