As a reinforcing material, the chemical inertness of aramid fiber leads to its poor adhesion to resin, wetting ability and interfacial bonding ability. Alfa Chemistry provides customers with aramid fiber surface modification services through a series of modification methods to deal with interface problems in aramid fiber composites. Our fiber development department has a strong technical base and a team of well-trained and experienced experts.
Why Is Surface Modification of Aramid Fibers Necessary?
The molecular chain of aramid fiber is composed of benzene rings and amide bonds alternately connected, with strong symmetry, and its orientation degree and surface crystallinity are high, that is, the surface has no side groups that can be firmly combined with the surrounding environment. This chemical structure makes the surface of the aramid fiber show greater chemical inertness, resulting in poor adhesion to the resin matrix, wetting ability and interfacial bonding ability. However, the interface is the key area for stress transfer, and weak interlaminar shear strength is not conducive to improving the overall performance of the composite. Therefore, surface modification treatment of aramid fibers can give full play to the potential of aramid fibers in reinforced composites.
Our Capabilities
Alfa Chemistry has a variety of aramid fiber surface modification technologies, and is ready to provide you with aramid fiber surface modification services. Our aramid fiber surface modification capabilities include but are not limited to the following:
- Chemical Graft Modification
Desired functional groups or molecular chains, such as amino groups, fluorinated groups, dopamine or polyphenols, can be modified on the surface of aramid fibers by chemical grafting. Under acid/base conditions, the surface of aramid will be hydrolyzed, resulting in the increase of reactive groups such as hydroxyl, carboxyl and amino groups. Therefore, acid-base assisted grafting is also an effective method for fiber surface modification.
Schematic diagram of selective fluorination of aramid fiber.[1]
- Surface Etch Modification
Our etching modification techniques include chemical etching and physical etching.
Chemical etching modification is to cause the hydrolysis of the amido bond in the main chain of the aramid fiber surface through chemical reaction with specific chemical reagents, thereby destroying the highly crystalline surface of the aramid fiber. Meanwhile, the use of some etching media will also introduce active groups such as amino and hydroxyl groups that are easily combined with the matrix on the surface of the aramid fiber.
Physical etching technology involves plasma treatment, ultrasonic treatment and γ-ray irradiation treatment, etc., which can roughen the surface of aramid fibers to promote the important role of the two-phase combination.
- Coating Method
The coating materials that have been studied for aramid fibers include water-based polyurethane, polyethylene glycol (PEG), rubber latex, etc.
Cooperate With Us
We are confident that, by working with us, you will be satisfied with our expertise in the production and characterization of aramid fiber modification service. We pride ourselves on our strengths in:
- Experienced testing and research team
- Meet customer needs at all stages
- Efficient and cost-effective services
- Complete and advanced infrastructure
Reference
Bo Zhang, et al. European Polymer Journal, 2021, 147, 110352.
Our products and services are for research use only.
