Intelligent textile materials self-healing materials - Flame retardant fabric_Flame retardant fabric_Cotton flame retardant fabric_Flame retardant fabric information platform

In the mid-1980s, people hoped to find intelligent material systems that integrate sensing, actuation, and information processing. The new development of textile technology in the 21st century has made it possible to produce “agile”, “dexterous” and “intelligent” fiber materials to produce smart textiles; or use conventional fabrics as a “platform” to add a variety of new chemical raw materials, Produce smart textiles. The concept of smart fibers comes from bionics, and generally achieves functions such as self-repair, self-adjustment, self-diagnosis, self-adaptation, and self-restoration from three aspects: bionics, molecular design, and composite technology.

Among them, polymer-based composites with self-healing functions have been a hot topic in academic research in recent years. At present, the development and research in this field has become a hot topic of great concern in the scientific community. As a new type of smart material, self-healing polymer matrix composites imitate the self-healing mechanism of biological damage to self-repair microscopic cracks that are difficult to detect with the naked eye during material processing or use.

The self-healing methods of polymer matrix composites mainly include intrinsic self-healing and external aid self-healing. The difference between the two is whether the self-healing system requires external repairing agents. Foreign-aided self-healing achieves the self-healing function by adding repairing agents inside and outside the material system. This article focuses on introducing foreign-aided self-healing materials.

Hollow fiber self-healing materials

The repair mechanism of the hollow fiber self-healing method is to embed the hollow fiber in the matrix material. The hollow fiber is filled with a repair agent fluid. When the material is damaged, the repair agent fluid in the hollow fiber is released to bond the crack to achieve self-repair of the damaged area.

Hollow fiber self-healing process

This method has been used in fiber-reinforced concrete materials for a long time. In recent years, many researchers have applied it to the field of self-healing of polymer-based composite materials. The diameter of hollow fibers is generally between 40 and 200 μm. It can be divided into three types according to the type of repair agent inside the fiber: The hollow fiber is filled with a single-component repair agent. This component can be used under the action of air, etc. without the need for a curing agent. Realize self-healing; the repairing agent and the curing agent are injected into different hollow fibers respectively. The self-repairing process requires the contact between the repairing agent and the curing agent to be realized; the repairing agent is injected into the hollow fiber, and the curing agent is dispersed in the matrix material in the form of microcapsules. The two need to be in contact to achieve self-healing function.

Nanoparticle self-healing materials

The self-healing mechanism of nanoparticles is: when a crack occurs in a material, the nanoparticles diffuse to the crack area (the smaller the size of the nanoparticles, the better the diffusion effect), and the diffused nanoparticle phase fills the crack to repair it.

Microcapsule self-healing materials

Microcapsule self-healing polymer materials were first proposed in 2001. In the following ten years, they became a research hotspot among researchers and have become one of the main self-healing methods currently. Its self-healing mechanism is as follows: microcapsules containing repair agents are embedded in a polymer matrix material, and a catalyst is pre-embedded in the matrix (the catalyst can also be microencapsulated and embedded in the matrix material). After the material cracks, The expansion of the crack causes the microcapsule to rupture, and the released repair agent diffuses to the damaged area under the action of siphon. After encountering the catalyst, a polymerization reaction occurs to repair the crack.

Microvascular self-healing materials

Although microcapsule self-healing systems are currently widely used, they can only achieve a single repair, and there is still a gap compared with ideal self-healing materials. In contrast, the microvessel network self-healing system first realized in 2007 simulates the self-healing principle of biological tissue and embeds microvessels with a three-dimensional network structure inside the material to achieve continuous replenishment of repair agents. Therefore, multiple repairs of material damage can be achieved.

Carbon nanotube self-healing

As a material self-healing system, the repair mechanism of carbon nanotubes is as follows: the carbon nanotubes embedded in the matrix material act as containers and store repair agent molecules inside. When the material cracks, the carbon nanotubes break and the repair agent is released. Then it is adsorbed at the crack or chemically reacts at the crack to bond the crack to achieve self-healing function. The carbon nanotube self-healing system is an ideal self-healing material system, but it is currently only in the computer simulation stage and there is no real experimental research. It is expected to be well applied in the future.

Self-healing polymer materials are currently in a rapidly developing research stage and belong to an interdisciplinary research field, so researchers with a variety of knowledge backgrounds are required to join. The main future development trends are: ① Optimize and develop new self-healing systems to improve repair efficiency and the number of self-healing cycles; ② The realization of self-healing function does not affect the performance of the base material; ③ Self-healing also has a self-diagnostic function, making self-healing polymerization Realize bionic materials in the true sense; ④ From laboratory research to engineering applications.

The development of smart materials has laid a solid foundation for the development of smart textiles and promoted the development of the high-end textile industry. We are bringing new buds to traditional textiles by applying smart materials to textiles or making textiles intelligent.

Source: Luyu Textile