Search

CN-122013447-A - Carbon fiber polyester composite felt and preparation method thereof

CN122013447ACN 122013447 ACN122013447 ACN 122013447ACN-122013447-A

Abstract

The invention discloses a carbon fiber polyester composite felt and a preparation method thereof, relating to the technical field of high polymer materials, comprising the following steps of (1) carbon fiber directional activation; the method comprises the steps of (1) in-situ grafting of sheath-core monofilaments, (3) synchronous lapping of double networks, and (4) in-situ thermal consolidation of nodes. According to the invention, the carbon fiber directional activation, the skin-core monofilament in-situ grafting, the double-network synchronous lapping and the node in-situ thermal consolidation are sequentially implemented to construct the carbon fiber polyester composite felt preparation system without an external binder, so that the molecular level cooperative combination of the carbon fiber and the polyester component is realized.

Inventors

  • WU XINQI
  • ZHANG RONGHUA
  • LONG HUA

Assignees

  • 江苏新鸿元新材科技有限公司

Dates

Publication Date
20260512
Application Date
20260330

Claims (10)

  1. 1. The preparation method of the carbon fiber polyester composite felt is characterized by comprising the following steps of: (1) Introducing continuous carbon fiber into a low-power oxygen plasma gas-phase activation cavity, performing pulse directional activation treatment, and introducing single-active hydroxyl functional groups into defect sites and axial active sites on the surface of the carbon fiber to prepare activated carbon fiber; (2) Continuously introducing activated carbon fibers into a closed grafting reaction kettle, uniformly loading a comb-shaped polybutylene succinate homooligomer in a molten state on the surface of a single carbon fiber by a normal pressure vapor deposition method, and enabling a prepolymer main chain and single-ended covalent anchoring of single-active hydroxyl functional groups on the surface of the carbon fiber to prepare the composite monofilament with a skin-core structure; (3) Cutting, opening, carding and directionally lapping the composite monofilaments of the sheath-core structure to a fixed length to form a main bearing framework fiber net, and synchronously inserting polybutylene succinate chopped fibers into pores of the main bearing framework fiber net in a multi-orientation cross lapping mode to prepare an interpenetrating double-network fiber net; (4) And (3) node in-situ thermal consolidation, namely introducing the double-network fiber net into a low-temperature thermal consolidation oven, and performing pressureless thermal treatment in a pre-crystallization temperature range lower than the melting point of the polybutylene succinate so as to enable the comb-shaped polybutylene succinate homologous prepolymer side chain and the polybutylene succinate chopped fiber to perform in-situ co-crystallization and transesterification reaction, and forming a molecular-level bonding layer at the cross-entanglement node to prepare the carbon fiber polyester composite felt without an external binder.
  2. 2. The method for preparing the carbon fiber polyester composite felt according to claim 1, wherein in the step (1), the excitation frequency of the low-power oxygen plasma gas-phase activation cavity is 13.56MHz, and the working environment is normal pressure; The treatment power of the pulse directional activation is 10-200W, the pulse duty ratio is 10% -50%, the oxygen inlet flow is 5-50 mL/min, and the activation time is 5-60 min.
  3. 3. The preparation method of the carbon fiber polyester composite felt according to claim 1, wherein in the step (2), an ultrasonic atomization device with power of 200-800W is adopted in a normal pressure vapor deposition method, and a molten comb-shaped polybutylene succinate homooligomer with temperature of 120-150 ℃ is atomized to form a molecular-grade vapor phase component; The grafting reaction temperature is 100-140 ℃ and the reaction time is 10-90 min.
  4. 4. The method for preparing the carbon fiber polyester composite felt according to claim 1, wherein in the step (3), the cutting length of the sheath-core structure composite monofilament is 3 mm-12 mm; The length of the polybutylene succinate chopped fiber is 3-12 mm, and the melting point is 115-120 ℃.
  5. 5. The method for preparing the carbon fiber polyester composite felt according to claim 1, wherein in the step (4), the heat treatment temperature is 95-109 ℃, the heat treatment time is 5-40 min, and the whole melting of the polybutylene succinate chopped fibers is not caused in the heat treatment process.
  6. 6. The preparation method of the carbon fiber polyester composite felt according to claim 1, wherein the comb-shaped polybutylene succinate homopolymer prepolymer in the step (2) has a main chain of a single-end carboxyl-terminated polybutylene succinate homopolymer chain segment, and has a number average molecular weight of 3000g/mol to 20000g/mol; The main chain is grafted with homopolymerized branched chains which are completely consistent with the structural units of the polybutylene succinate, the number of the grafted side chains of each main chain is 3-12, the number average molecular weight of the side chains is 1000-8000 g/mol, and the tail ends of the side chains are hydroxyl active end groups.
  7. 7. The method for preparing the carbon fiber polyester composite felt according to claim 1, wherein the continuous carbon fiber in the step (1) is one or more of polyacrylonitrile-based carbon fiber, pitch-based carbon fiber and viscose-based carbon fiber, and the linear density is 6K-24K.
  8. 8. The method for preparing the carbon fiber polyester composite felt according to claim 1, wherein in the step (3), the mass ratio of the main bearing framework fiber web to the fiber web formed by the polybutylene succinate chopped fibers is 3:7-7:3.
  9. 9. The method for preparing the carbon fiber polyester composite felt according to claim 1, wherein the mass ratio of the continuous carbon fiber in the step (1) to the comb-shaped polybutylene succinate homopolymer in the step (2) is 10:1-1:2.
  10. 10. The carbon fiber polyester composite felt is characterized in that the carbon fiber polyester composite felt is prepared by the preparation method of the carbon fiber polyester composite felt according to any one of claims 1-9, and comprises a main bearing framework fiber web formed by composite monofilaments with a sheath-core structure and a polybutylene succinate chopped fiber web inserted into framework pores, wherein molecular-grade bonding layers are formed at fiber crossing nodes through in-situ co-crystallization and transesterification reaction, and the carbon fiber polyester composite felt does not contain an additional binder.

Description

Carbon fiber polyester composite felt and preparation method thereof Technical Field The invention relates to the technical field of high polymer materials, in particular to a carbon fiber polyester composite felt and a preparation method thereof. Background The carbon fiber polyester composite felt has the advantages of high strength, high modulus, electric conduction and heat conduction, flexibility of polyester fibers, easiness in forming and weather resistance, and can improve the overall strength and rigidity of the composite material, optimize the surface evenness, reduce defects, enhance the weather resistance and ultraviolet resistance, improve the resin infiltration efficiency, improve the forming process, realize electromagnetic shielding, heat insulation and heat preservation, and be suitable for manufacturing lightweight and high-performance components. In the prior art, the preparation of the carbon fiber polyester composite felt has the problems of poor interfacial compatibility of carbon fibers and a polyester matrix, easiness in layering and falling, reduced mechanical property caused by adding an external binder, complex preparation process and insufficient environmental protection, and also has the problems of uneven surface activation, poor grafting effect, obvious mechanical property anisotropy of the composite felt, loose structure, easiness in damaging fibers in a thermal consolidation process, higher energy consumption and the like, thereby influencing the structural integrity, mechanical bearing stability and comprehensive use performance of the composite felt. Based on the above, the invention provides a carbon fiber polyester composite felt and a preparation method thereof. Disclosure of Invention The invention aims to provide a carbon fiber polyester composite felt and a preparation method thereof, wherein a preparation system without an additional binder is constructed through four steps of carbon fiber directional activation, sheath-core monofilament in-situ grafting, double-network synchronous lapping and node in-situ thermal consolidation, so that molecular-level combination of carbon fibers and polyester components is realized, the interface bonding strength, the structural integrity and the mechanical bearing stability are obviously improved, and the problems of poor interface compatibility, easiness in layering and falling off, performance reduction caused by the additional binder, complex process and insufficient environmental protection are solved. In order to achieve the above purpose, the present invention provides the following technical solutions: the preparation method of the carbon fiber polyester composite felt comprises the following steps: (1) Introducing continuous carbon fiber into a low-power oxygen plasma gas-phase activation cavity, performing pulse directional activation treatment, and introducing single-active hydroxyl functional groups into defect sites and axial active sites on the surface of the carbon fiber to prepare activated carbon fiber; (2) Continuously introducing activated carbon fibers into a closed grafting reaction kettle, uniformly loading a comb-shaped polybutylene succinate homooligomer in a molten state on the surface of a single carbon fiber by a normal pressure vapor deposition method, and enabling a prepolymer main chain and single-ended covalent anchoring of single-active hydroxyl functional groups on the surface of the carbon fiber to prepare the composite monofilament with a skin-core structure; (3) Cutting, opening, carding and directionally lapping the composite monofilaments of the sheath-core structure to a fixed length to form a main bearing framework fiber net, and synchronously inserting polybutylene succinate chopped fibers into pores of the main bearing framework fiber net in a multi-orientation cross lapping mode to prepare an interpenetrating double-network fiber net; (4) And (3) node in-situ thermal consolidation, namely introducing the double-network fiber net into a low-temperature thermal consolidation oven, and performing pressureless thermal treatment in a pre-crystallization temperature range lower than the melting point of the polybutylene succinate so as to enable the comb-shaped polybutylene succinate homologous prepolymer side chain and the polybutylene succinate chopped fiber to perform in-situ co-crystallization and transesterification reaction, and forming a molecular-level bonding layer at the cross-entanglement node to prepare the carbon fiber polyester composite felt without an external binder. Preferably, in the step (1), the excitation frequency of the low-power oxygen plasma gas-phase activation cavity is 13.56MHz, and the working environment is normal pressure; The treatment power of the pulse directional activation is 10-200W, the pulse duty ratio is 10% -50%, the oxygen inlet flow is 5-50 mL/min, and the activation time is 5-60 min. Preferably, in the step (2), an ultrasonic atomization device with