The problem of burning and dripping of aluminum-plastic panels: the inhibition mechanism of brucite powder
Aluminum plastic panels are widely used in building decoration materials due to their lightweight, aesthetic appeal, and excellent processing performance. However, when encountering a fire, aluminum-plastic panels, especially the plastic core material inside, are prone to melting and dripping, which not only accelerates the spread of flames but may also lead to more serious consequences. Therefore, how to effectively suppress dripping during the combustion process has become the key to improving the fire safety of aluminum-plastic panels. In recent years, brucite powder (mainly composed of magnesium hydroxide) has shown significant effectiveness as an environmentally friendly flame retardant in solving this problem.
1、 The hazards of burning and dripping of aluminum-plastic panels
When aluminum-plastic panels are subjected to high temperatures, the plastic components begin to soften and eventually melt, forming liquid droplets. These droplets not only directly increase the level of chaos at the fire scene, but they may also continue to burn or ignite other flammable substances, thereby exacerbating the spread of the fire. In addition, the presence of droplets may also obstruct escape routes and pose a serious threat to the safety of personnel.
2、 Characteristics of brucite powder as a flame retardant
Magnesite powder is an inorganic powder made from finely processed natural minerals, mainly composed of magnesium hydroxide (Mg (OH) ₂). It has the following characteristics that make it an ideal flame retardant material:
Efficient heat absorption: During the thermal decomposition process, brucite powder can absorb a large amount of heat and release water vapor, effectively reducing the temperature of the surrounding environment.
No toxic gases produced: Unlike traditional halogen flame retardants, brucite powder does not release any harmful gases during combustion, reducing the risk of secondary pollution.
Improving the mechanical properties of materials: Adding an appropriate amount of brucite powder can enhance the strength and toughness of composite materials, and improve their durability.
3、 Mechanism of Water Magnesium Stone Powder Inhibiting Combustion Dripping
The reason why brucite powder can effectively suppress the dripping phenomenon of aluminum-plastic panels during combustion is mainly attributed to the following mechanisms:
1. Heat absorption and cooling
When heated above 340 ℃, brucite powder begins to decompose into magnesium oxide and water vapor, which is a strong endothermic reaction. By absorbing a large amount of heat, it can significantly reduce the temperature of the material surface and its vicinity, preventing the plastic matrix from reaching its melting point too early, thereby reducing or even avoiding the occurrence of dripping.
2. Form a protective layer
As water evaporates, the magnesium oxide left behind after the decomposition of brucite powder will form a dense protective film on the surface of the material. This layer of membrane not only blocks the infiltration of external oxygen into the interior, but also prevents substances that have not been completely burned from escaping outward, further suppressing the dripping phenomenon.
3. Increase viscosity
In some cases, brucite powder can also increase the viscosity of the polymer matrix, making the material less prone to flow and deformation even at high temperatures. A higher viscosity helps maintain the integrity of the material structure and reduces the possibility of dripping caused by melting.
4. Reduce smoke generation
Due to the fact that the decomposition of brucite powder mainly produces water vapor rather than harmful gases, it can significantly reduce the amount of smoke generated during combustion. Less smoke means higher visibility, which is conducive to personnel evacuation and also reduces interference with firefighting and rescue work.
4、 Application examples and effectiveness verification
In practical applications, satisfactory fire modification effects have been achieved by mixing a certain proportion of brucite powder into the plastic core material of aluminum-plastic panels. For example, in some aluminum-plastic panel products that use high-quality brucite powder as an additive, test results show that their fire resistance level has reached B1 or even A2 standards, greatly exceeding the protection level of ordinary products. More importantly, under simulated fire conditions, these boards exhibit significant anti drip properties, greatly improving the overall safety factor.
Although brucite powder has shown excellent ability in suppressing the burning and dripping of aluminum-plastic panels, there are still several directions worth further exploration:
Optimize the ratio: Study how to adjust the optimal addition ratio of brucite powder according to different application scenarios to achieve the best comprehensive performance.
Technological innovation: Develop new production processes and technological means to ensure that brucite powder can be evenly distributed in aluminum-plastic panels, fully exerting its flame retardant effect.
Broaden the application range: in addition to aluminum plastic plate, try to apply brucite powder to more types of building materials, such as extruded plate, polystyrene foam plate, etc., to promote the development of the entire construction industry towards a safer and environmentally friendly direction.
In summary, brucite powder, with its unique physical and chemical properties, provides an effective solution to the problem of burning and dripping in aluminum-plastic panels. With the advancement of technology and market recognition, it is believed that this environmentally friendly flame retardant will play an increasingly important role in the field of building fire prevention in the future.