Interface-enhanced carbon fiber/polycaprolactam composite material and preparation method thereof

Abstract

The invention relates to an interface-enhanced carbon fiber / polycaprolactam composite material and a preparation method thereof, and specifically discloses a preparation method of the interface-enhanced carbon fiber / polycaprolactam composite material. Specifically, carbon fibers are adopted to be reacted with hexachlorocyclotriphosphazene with multiple functional groups to improve reaction active points of carbon fiber surfaces, polycaprolactam is compounded with the carbon fiber surfaces by the in situ grafting way in the ring-opening polymerization process, thereby effectively improving interface strength of the carbon fiber polycaprolactam and the matrix polycaprolactam and overcoming the defects that grafting degree of polycaprolactam on the carbon fiber surfaces and improvement degree in interface performance of the composite material are low in an existing method.

Description

technical field

[0001] The invention belongs to the field of polymer materials, in particular to the field of interface modification of composite materials, and more specifically relates to an interface-reinforced carbon fiber / polycaprolactam composite material and a preparation method thereof. Background technique

[0002] Polycaprolactam, also known as polyamide 6 (nylon 6), is an important thermoplastic engineering plastic, but its hygroscopicity is large, the dimensional stability of the product is poor, and the strength and hardness are far inferior to metal. In order to overcome these shortcomings, as early as 70 Before the 1990s, people used carbon fiber to strengthen and modify it, and the strength and rigidity of the obtained carbon fiber reinforced polyamide composite material were significantly improved, the high temperature creep was small, the thermal stability was significantly improved, the dimensional accuracy was good, and the wear resistance and damping were...

Examples

preparation example Construction

[0094] Now further illustrate the preparation method of the carbon fiber / polycaprolactam composite material of the present invention in conjunction with specific embodiments of the present invention, comprising steps:

[0095] (i) In an inert solvent, in the presence of an acid-binding agent, the carbon fiber is reacted with hexachlorocyclotriphosphazene to form a carbon fiber whose surface is modified with hexachlorocyclotriphosphazene.

[0096] Preferably, the carbon fibers described in step (i) are carbon fibers that have undergone surface oxidation treatment in advance.

[0097] (ii) reacting the carbon fiber whose surface is modified with hexachlorocyclotriphosphazene obtained in step (i) with a caprolactam monomer to form a carbon fiber whose surface is grafted with a caprolactam monomer.

[0098] (iii) reacting the carbon fiber grafted with caprolactam monomer on the surface obtained in step (ii) with the caprolactam monomer, an initiator and an activator, thereby formi...

Embodiment 1

[0131] The preparation of embodiment 1 composite material 1

[0132] Step (1) Oxidation treatment of carbon fiber precursors (unsized): put 1 part by weight of carbon fiber into 100 parts by weight of 98% sulfuric acid, then reflux for 2 hours at a temperature of 100 ° C, then filter and wash with deionized water until The washing solution is neutral, and the surface oxidized carbon fibers are obtained by drying at a temperature of 60°C;

[0133] Step (2) Preparation of carbon fibers with caprolactam on the surface: put triethylamine and carbon oxide fibers into dry tetrahydrofuran according to a weight ratio of 10:100, then dissolve 5 parts by weight of hexachlorocyclotriphosphazene in tetrahydrofuran and slowly add In the above reaction solution, reflux reaction at 60°C for 12 hours, then add 8 parts by weight of caprolactam, and then reflux reaction at 60°C for 24 hours, then wash with tetrahydrofuran and deionized water for 4 to 5 times respectively Remove unreacted hexac...

Embodiment 2

[0136] The preparation of embodiment 2 composite material 2

[0137] Step (1) carbon fiber precursor (unsized) oxidation treatment: put 5 parts by weight of carbon fiber into 20 parts by weight of 60% nitric acid and 80 parts by weight of 98% sulfuric acid, and then reflux at a temperature of 100 ° C for 4 hours, and then Filter and wash with deionized water until the washing liquid is neutral, and dry at a temperature of 100°C to obtain surface oxidized carbon fibers;

[0138] Step (2) Preparation of carbon fibers with caprolactam on the surface: put triethylamine and carbon oxide fibers into dry tetrahydrofuran according to a weight ratio of 30:100, then dissolve 15 parts by weight of hexachlorocyclotriphosphazene in tetrahydrofuran and slowly add In the above reaction solution, reflux reaction at 65°C for 24 hours, then add 20 parts by weight of caprolactam, and then reflux reaction at 65°C for 18 hours, then wash with tetrahydrofuran and deionized water for 4 to 5 times re...

technical field

[0001] The invention belongs to the field of polymer materials, in particular to the field of interface modification of composite materials, and more specifically relates to an interface-reinforced carbon fiber / polycaprolactam composite material and a preparation method thereof. Background technique

[0002] Polycaprolactam, also known as polyamide 6 (nylon 6), is an important thermoplastic engineering plastic, but its hygroscopicity is large, the dimensional stability of the product is poor, and the strength and hardness are far inferior to metal. In order to overcome these shortcomings, as early as 70 Before the 1990s, people used carbon fiber to strengthen and modify it, and the strength and rigidity of the obtained carbon fiber reinforced polyamide composite material were significantly improved, the high temperature creep was small, the thermal stability was significantly improved, the dimensional accuracy was good, and the wear resistance and damping were...

Examples

preparation example Construction

[0094] Now further illustrate the preparation method of the carbon fiber / polycaprolactam composite material of the present invention in conjunction with specific embodiments of the present invention, comprising steps:

[0095] (i) In an inert solvent, in the presence of an acid-binding agent, the carbon fiber is reacted with hexachlorocyclotriphosphazene to form a carbon fiber whose surface is modified with hexachlorocyclotriphosphazene.

[0096] Preferably, the carbon fibers described in step (i) are carbon fibers that have undergone surface oxidation treatment in advance.

[0097] (ii) reacting the carbon fiber whose surface is modified with hexachlorocyclotriphosphazene obtained in step (i) with a caprolactam monomer to form a carbon fiber whose surface is grafted with a caprolactam monomer.

[0098] (iii) reacting the carbon fiber grafted with caprolactam monomer on the surface obtained in step (ii) with the caprolactam monomer, an initiator and an activator, thereby formi...

Embodiment 1

[0131] The preparation of embodiment 1 composite material 1

[0132] Step (1) Oxidation treatment of carbon fiber precursors (unsized): put 1 part by weight of carbon fiber into 100 parts by weight of 98% sulfuric acid, then reflux for 2 hours at a temperature of 100 ° C, then filter and wash with deionized water until The washing solution is neutral, and the surface oxidized carbon fibers are obtained by drying at a temperature of 60°C;

[0133] Step (2) Preparation of carbon fibers with caprolactam on the surface: put triethylamine and carbon oxide fibers into dry tetrahydrofuran according to a weight ratio of 10:100, then dissolve 5 parts by weight of hexachlorocyclotriphosphazene in tetrahydrofuran and slowly add In the above reaction solution, reflux reaction at 60°C for 12 hours, then add 8 parts by weight of caprolactam, and then reflux reaction at 60°C for 24 hours, then wash with tetrahydrofuran and deionized water for 4 to 5 times respectively Remove unreacted hexac...

Embodiment 2

[0136] The preparation of embodiment 2 composite material 2

[0137] Step (1) carbon fiber precursor (unsized) oxidation treatment: put 5 parts by weight of carbon fiber into 20 parts by weight of 60% nitric acid and 80 parts by weight of 98% sulfuric acid, and then reflux at a temperature of 100 ° C for 4 hours, and then Filter and wash with deionized water until the washing liquid is neutral, and dry at a temperature of 100°C to obtain surface oxidized carbon fibers;

[0138] Step (2) Preparation of carbon fibers with caprolactam on the surface: put triethylamine and carbon oxide fibers into dry tetrahydrofuran according to a weight ratio of 30:100, then dissolve 15 parts by weight of hexachlorocyclotriphosphazene in tetrahydrofuran and slowly add In the above reaction solution, reflux reaction at 65°C for 24 hours, then add 20 parts by weight of caprolactam, and then reflux reaction at 65°C for 18 hours, then wash with tetrahydrofuran and deionized water for 4 to 5 times re...

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