The hottest interpretation of the development and

Interpretation: the development and changes of the foamed plastic market in 2009

2009 was jokingly called a "hot" year. Whether it was the fire of the North annex building of the CCTV new building or the "fire camp" staged in Beichuan, which has experienced the earthquake, without exception, pointed the spearhead at plastic building materials and plates, The flame retardancy of polystyrene and polyurethane foams and plates has aroused widespread concern in the industry, with the support of the rapid growth of the world construction market. Correspondingly, phenolic (PF) foam also shines because of its excellent flame retardant and thermal insulation properties! Nowadays, when energy conservation and emission reduction are advocated, "replacing steel with plastic" has become the main theme of the development of auto parts industry. Among them, many auto interiors are micro foamed foam plastic products, which is the so-called "success or failure". Different foamed plastics have different functions. 2009 is destined to usher in a new era in which foamed plastics will lead the trend. Now let's take a systematic look at the development and functions of foamed plastics

foamed plastics are also called porous plastics. Plastic with countless micropores inside made of resin as the main raw material. It is light in weight. If the drive cannot work normally, it is hot, sound-absorbing, shockproof and corrosion-resistant. It is widely used as heat insulation, sound insulation, packaging materials and vehicle hull. There are many classification methods of foamed plastics, and there are three common ones. According to the hardness classification, it can be divided into three categories: soft foams, hard foams and semi-rigid foams. The elastic modulus of soft foam is less than 70MPa; The elastic modulus of rigid foam is greater than 700MPa; The elastic modulus of semi-rigid foam plastic is 70~700mpa. According to the density classification, it can be divided into low foaming, medium foaming and high foaming plastics. The density of low hair foam plastic is greater than 400kg/m3; The density of medium foamed plastic is 100~400kg/m3; The density of high foam plastic is less than 100kg/m3. According to the classification of bubble structure, the microcellular connected with each other is called open cell foam, and the closed cell foam is called closed cell foam

there are many kinds of foamed plastics, which we often contact in our daily life: polystyrene foamed plastics, polyurethane foamed plastics, polypropylene foamed plastics, PVC foamed plastics, phenolic foamed plastics, epoxy foamed plastics, etc. Among them, polystyrene foam and phenolic foam are the most widely used

recently, Beijing's upcoming standard for temporary housing with colored steel panels as core materials such as polystyrene and polyurethane has given people a deeper understanding of polystyrene building materials. From the material analysis of color steel plate, color coated steel plate is the surface material, and the core material mainly includes polystyrene, polyurethane and rock wool. At present, most of the color steel plate insulation materials in the city are polystyrene and polyurethane. Although these materials have the advantages of light weight, low cost and simple operation, they have extremely low ignition point and poor flame retardancy. In the process of building color steel plate houses, polystyrene and polyurethane are exposed, which are easy to be directly ignited by open flame operations such as electric welding, gas welding, cutting machines, etc; After the color steel plank house is completed and put into use, it is easy to ignite polystyrene or polyurethane in the interlayer by connecting wires randomly, which is close to the heat source and fire source. When polystyrene is burned, it will release styrene gas that pollutes the environment, which is also its insurmountable disadvantage at present

a few days ago, Guangzhou fire protection organization manpower carried out a comprehensive demolition of polyurethane foam in the No. 7 residence of Guangzhou Gymnasium, thus opening the prelude to the rectification of the decoration behavior of using polyurethane foam in public places and entertainment places in Guangzhou. The dismantling of foamed plastics in Guangzhou Gymnasium has also made people aware that many places with serious consequences such as mass casualties are mostly decorated with flammable and combustible materials such as polyurethane foams

polyurethane foams are generally used for the decoration of public gathering places such as hotels, guesthouses and entertainment places. In the fire acceptance standard, although these materials belong to inflammables, polyurethane foam materials that meet the flame retardant standard are not included in the constituent elements of fire acceptance, but this situation has changed at present. Because the use of polyurethane foam to decorate houses has two disadvantages - Co, hydrogen sulfide and hydrogen chloride produced by this material during combustion are highly toxic gases, and people will fall to the ground after inhaling two or three mouthfuls; At the same time, the "thick" smoke is too thick, so that the masses cannot see the road when escaping

it is precisely because of the limitations of polystyrene and polyurethane foams in flame retardancy that phenolic foams have developed rapidly. Phenolic foam is a new type of foam developed in recent years. It is ranked in the forefront of all foam plastics because of its good flammability, low smoke emission, stable high-temperature performance, thermal insulation, sound insulation, easy molding and processing, and good durability. It is called the third generation of emerging thermal insulation materials

the birth of phenolic foam adds new members to thermal insulation materials. Especially valuable is that it combines the advantages of organic and inorganic thermal insulation materials: light weight, good thermal insulation performance, low water absorption, good strength, good dimensional stability, and excellent fire resistance. Experts emphasized that phenolic foam can be used as the environmental protection and fire-proof thermal insulation material for building exterior wall insulation. Especially in terms of flame retardancy and toxicity, it has special excellent properties: ① it is difficult to burn, self extinguishing, low smoke, resistant to flame penetration, free of drops in case of fire, little toxic gas, and the oxygen index is generally 35 ~ 40, which is the top of organic foam; ② Good heat resistance. The long-term service temperature can generally reach 130 ℃ ~ 150 ℃, which is 30 ℃ ~ 40 ℃ higher than that of polyurethane hard foam; ③ The thermal conductivity is generally 0.029 ~ 0.04w/m · K, which is close to polyurethane hard foam and better than polystyrene foam materials widely used in the current construction industry

industry experts also said that in view of the current development considerations of energy conservation, emission reduction and green environmental protection, phenolic foam, as a green, safe and economic heat preservation and fire prevention material, just meets the stringent requirements of the current market, and will definitely have a market prospect better than other types of foam plastics. It is expected that it will grow at an average annual rate of 20% in the future

experts from relevant construction departments in France and Northern Europe believe that among the existing foams, only phenolic foams have good fire resistance, and the toxic smoke released in case of fire is the smallest among all foam materials, and the pollution to the environment is also the smallest. Phenolic foam has been widely used in public buildings in the former Soviet Union and Eastern Europe. Western Europe and the Middle East stipulate that phenolic foam is preferred as insulation material in new projects, and France uses phenolic foam as a material for sealing and controlling fire. In recent years, Japan has also begun to apply phenolic foam in large quantities. The Ministry of construction of Japan issued the decree "phenolic foam as a standard building fire-resistant material"

note: the reprinted content is indicated with the source. The reprint is for the purpose of transmitting more information, and does not mean to agree with its views or confirm the authenticity of its content