Popularization of new technical knowledge of flame retardants

The purpose of flame retardant technology is to make non-flame retardant materials It is not easy to burn or can self-extinguish under certain conditions. It is a material that provides safety guarantees. The development direction of flame retardants in the future is good flame retardant effect, safety and environmental protection. To this end, considerable manpower and resources have been invested in the research and development of new flame retardant technologies. Nowadays, several new flame retardant technologies have been developed one after another. Next, the editor will introduce several new flame retardant technologies of environmentally friendly flame retardants.

1. Surface modification

Inorganic flame retardants have strong polarity and hydrophilicity, poor compatibility with non-polar polymer materials, and it is difficult to form a good combination and adhesion at the interface. In order to improve the adhesion and interfacial affinity between it and the polymer, surface treatment with coupling agent is one of the most effective methods. Commonly used coupling agents are silanes and titanates. For example, ATH treated with silane has a good flame retardant effect, which can effectively improve the bending strength of polyester and the tensile strength of epoxy resin; ATH treated with ethylene-silane can be used to improve the resistance of crosslinked ethylene vinyl acetate copolymer. Flammability, heat resistance and moisture resistance. Titanate coupling agents and silane coupling agents can be used together to produce synergistic effects. The surface activity of ATH after surface modification treatment has been improved, the affinity with the resin has been enhanced, the physical and mechanical properties of the product have been improved, the processing fluidity of the resin has been increased, the moisture absorption rate of the ATH surface has been reduced, and the Various electrical properties of flame-retardant products, and improve the flame-retardant effect from V21 to V20.

Two, ultra-fine

Inorganic flame retardants have the advantages of high stability, low volatility, low smoke toxicity, and low cost, and are more and more popular among people. However, its compatibility with synthetic materials is poor, and the addition amount is large, which reduces the mechanical properties and heat resistance of the material. Therefore, modifying inorganic flame retardants to enhance their compatibility with synthetic materials and reduce their dosage has become one of the development trends of inorganic flame retardants. At present, the ultrafine and nanometerization of aluminum hydroxide ( 3 Al(OH) ) is the main research and development direction. The addition of a large amount of 3 Al(OH) will reduce the mechanical properties of the material, and the micronization of 3 Al(OH) and refilling will instead have the effect of plasticizing and strengthening rigid particles, especially nano-scale materials. Since the flame retardant effect is dominated by chemical reactions, the smaller the particle size of the same amount of flame retardant, the larger the specific surface area and the better the flame retardant effect. Ultra-fine is also considered from the aspect of affinity. It is precisely because of the difference in polarity between aluminum hydroxide and the polymer that the physical and mechanical properties of its flame-retardant composite material decrease. The ultra-fine and nano-sized 3 Al(OH) enhances the interfacial interaction, can be uniformly dispersed in the matrix resin, and more effectively improves the mechanical properties of the blend.

3. Composite collaboration

In actual production and application, a single flame retardant always has one or another defect, and it is difficult to meet the increasingly higher requirements with a single flame retardant. The compounding technology of flame retardants is to compound among phosphorus, halogen, nitrogen and inorganic flame retardants, or within certain types to seek the best economic and social benefits. Flame retardant compounding technology can combine the strengths of two or more flame retardants to complement each other in performance, reduce the amount of flame retardants used, and improve the flame retardant performance, processing performance and physical and mechanical properties of materials.

Four, cross-linking

The flame retardancy of cross-linked polymers is much better than that of linear polymers. Adding a small amount of cross-linking agent in the processing of thermoplastics can make the plastic into a partial network structure, which can improve the dispersion of flame retardants, facilitate the formation of carbon when the plastics are burned, improve the flame retardant performance, and increase the durability of the product. Mechanical, heat resistance and other properties.

5. Microencapsulation

The application of microencapsulation to flame retardants is a new technology developed in recent years. The essence of microencapsulation is to crush and disperse the flame retardant into particles, encapsulate it with organic or inorganic substances to form a microcapsule flame retardant, or use inorganic substances with a large surface as a carrier to adsorb the flame retardant on these inorganic substances. In the void of the material carrier, a honeycomb microcapsule flame retardant is formed. The microencapsulation of bromine-based environmentally friendly flame retardants has the following advantages: it can improve the stability of flame retardants; it can improve the compatibility between flame The various properties of flame retardants expand its application range.

6. Nano Flame Retardant Technology

Some nanomaterials have the function of preventing combustion. Adding them as flame retardants to combustible materials can change the combustion performance of combustible materials by using their special size and structure effects, making them fireproof materials. The use of nanotechnology can change the flame retardant mechanism and improve the flame retardant performance. Due to the small particle size and large specific surface area of ​​nanoparticles, the characteristics of surface effect, volume effect, quantum size effect and macroscopic quantum tunneling effect provide new opportunities for the design and preparation of high-performance and multi-functional new materials. ideas and ways.

The above six technologies are the latest flame retardant technology research results. In the near future, more advanced technologies will be applied to flame retardant products.��, to provide a safer living environment for everyone.