Characteristics and application of melamine foam
一,Introduction
Melamine foam is a new type of foam with a high opening ratio of three-dimensional grid structure. It has excellent sound absorption, flame retardancy, heat insulation, moisture and heat stability, hygienic safety and good. Comprehensive performance such as secondary processing. These characteristics make the product a wide range of applications (such as building insulation noise reduction, transportation, transportation, aviation, electromechanical, electronics, household appliances, etc.) and broad market prospects.
二、The physical characteristics of melamine foam
(1) Sound absorption
Melamine foam is a full-opening three-dimensional grid structure system with a long aspect ratio of L/D of about 10 to 20, and its extremely high open porosity (density of 10kg/M3). The melamine foam has an open cell ratio of more than 99%, so that the sound wave can be easily and effectively entered into the deep layer of the foam and the vibration energy converted into a mesh can be consumed and absorbed, and the reflected wave can be effectively eliminated. The excellent absorption characteristics of low-frequency noise exhibited by melamine foam have attracted great interest from experts in the acoustic field.
(2) Flame retardant properties
The melamine foam begins to burn only when it comes into contact with an open flame. Once the combustion begins to decompose, a large amount of inert non-combustible gas is generated to slow down the burning speed, and at the same time, a dense coke layer is rapidly formed on the surface of the combustion body to effectively block the development of combustion to the deep layer, and the open flame automatically extinguishes after leaving. As a scientific evaluation standard, melamine foam can meet the B1 grade low flammability material standard (German standard) and UL94-V0 high flame retardant material standard (US) without adding flame retardant. Insurance Association Standard). The general foams, such as polyolefins, polystyrenes, polyurethanes, etc., are inherently flammable, in order to comply with relevant flame retardant regulations and standards, it is often necessary to add flame retardants, many of which are at high temperatures. It will decompose by heat and release toxic gases that can kill people, causing secondary disasters and environmental pollution in the event of a fire.
As two important indicators of material combustion evaluation, it is often ignored by users, that is, the dripping and smoke density of materials during the combustion process. Conventional foams, such as polyethylene, polystyrene, polyurethane, etc., melt and produce droplets when burned, and the burning droplets can quickly cause the spread of fire. Flame retardant modification is powerless for this fatal flaw in the above materials. At the same time, polystyrene and polyurethane also produce a large amount of toxic fumes in the combustion process. The addition of flame retardant modification and smoke inhibitors often brings about side effects such as increased toxicity and cost. The melamine foam is cokeed during burning without generating droplets, and the amount of smoke generated is much lower than that of the above materials, and the toxicity is much smaller than the above materials.
(3) Thermal stability
Melamine foam is a thermosetting plastic with a high three-dimensional network cross-linking structure, which has higher thermal stability than polyethylene and polystyrene thermoplastics and polyurethanes with lower cross-linking. And aging resistance. The melamine foam can work under the condition of 150 °C for a long time, and can work under the working condition of 180 °C for a short time without decomposition and deformation. Only when it is in a high temperature environment above 400 °C, obvious decomposition occurs. phenomenon. The working temperature of foams such as polyolefin, polystyrene and polyurethane is only 80 ° C. When it exceeds 80 ° C, deformation and decomposition occur.
(4) Thermal insulation
Melamine foam is an extremely lightweight material with an open cell ratio of over 95%. The three-dimensional grid structure effectively blocks the convective heat transfer of air, and the unique thermal stability makes it a special Lightweight insulation that is difficult to replace.
(5) Chemical and hygienic resistance
The melamine foam is made by high-temperature foaming, and there is no residual free formaldehyde; its stable chemical structure and cross-linking system make it have unique chemical stability, and its hygienic properties can meet the food hygiene requirements. These characteristics have made it widely used in the fields of daily necessities, interior decoration and noise reduction decoration of vehicles.
(6) Post-processability
The melamine foam can be conveniently processed into a sheet, a profiled material by means of cutting, cutting, boring, etc., and a sound absorbing product which is processed into a tapered and tapered shape to meet the sound absorption requirement.
The melamine foam can be surface treated by spraying to improve its surface properties. The surface of melamine foam can be treated with Heplon and urethane to adjust its hygroscopicity and improve the self-cleaning of its surface. This type of product has become an important member of the family of sound absorbing materials.
The open-cell characteristics of melamine foam make it possible to add new functions to it by means of impregnation. After immersion treatment with compound phosphate, it can meet the standard of German DIN B0 grade flame-retardant building materials; high-strength open-cell foam can be obtained by impregnation with rubber emulsion such as silicone; impregnated with dielectric material, An absorbing material for radio waves and microwaves is obtained; a special surfactant is used for impregnation to obtain a photo-scratch of a car and a stainless steel.
The melamine foam sheet can be made into a embossed acoustical ceiling and coil by hot pressing, and the surface strength is improved; the sheet with a density of 2-3kg/M3 can be made into a non-woven fabric by hot pressing. Cloth "the same coil.
The polar nature of melamine foam makes it easy to dye, making it a colorful hanging sound absorbing material, while being more decorative.
Melamine foam can be easily combined with metal and non-metal, lightweight and heavy, flexible and brittle, textile and non-woven fabrics, and a variety of materials to produce a series of sound-absorbing and thermal insulation products. , to give the product additional quality and function to meet the needs of different places and working conditions. For example, transparent polyester film, aluminized polyester film and melamine foam composite product; aluminum foil and melamine foam composite product; flame retardant woolen decorative cloth and various non-woven fabrics and melamine foam composite products; rigid skeleton Filled products and so on.
In addition to lower bulk density and chemical resistance than other foams, melamine foam has outstanding sound absorption, especially for low frequency noise, outstanding thermal stability and aging resistance, outstanding flame retardant. Low smoke and hygiene. Outstanding post-processing not only enhances its inherent advantages, but also provides a range of rare new materials that have been expanded. These outstanding new materials are widely used in various industrial fields such as construction, transportation, electronic information, aerospace, and daily chemical, especially in the conditions of flame retardant, high temperature, low frequency noise absorption requirements, and become irreplaceable materials.
In addition, it is also widely used in the noise treatment of boiler rooms, compressor rooms, pumping stations, stamping workshops and blowers. The above-mentioned fields of application are more dangerous to fire and more demanding, and melamine foam is a rare material that can meet these requirements at the same time.
Due to its good thermal insulation and sound insulation properties, melamine foam, especially its comprehensive properties such as fire resistance and thermal stability, it is possible to replace polystyrene and polyurethane in household appliances such as electric water heaters, refrigerators and disinfection cabinets. It is widely used in foam plastics. Melamine foam is used as an absorption and shielding material for radio waves, radar and microwave energy after being impregnated or composited by dielectric materials, and will be widely used in the information industry and military industry.
The construction of urban expressways in China has entered a stage of rapid development. The problem of road noise disturbance has been mentioned on the government's agenda. Experts predict that melamine foam has great market potential in the field of noise reduction in highways.
Melamine foam is used in home computers and workstations to eliminate the noise generated by various drives and fans.
Vehicle noise is one of the important indicators for evaluating car quality. The reduction of internal noise of the vehicle will greatly improve the comfort of drivers and passengers. The noise in the car is mainly from the vibration of the engine, the friction between the wheel and the ground, the howling of the air and the resonance of the car body. In addition to measures to improve the rigidity of the chassis and eliminate the low-frequency resonance zone, it is mainly eliminated by isolation and absorption. From the point of view of energy conservation, the materials required are lightweight; from a safety point of view, the materials are required to have fire and heat resistance properties. The advent of melamine foam and its various multifunctional composite materials has made it possible to improve the noise immunity, safety and energy saving of vehicles. Melamine foam has a large number of applications in transportation such as ships, trains and airplanes.
This article is organized by Life Nano-Plastic Product (Zhangzhou) Co., Ltd!
More details on Website: www.lfsponge.com
