Features of phenolic board

21/06/2022
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The system structure of phenolic board is mainly composed of: bonding layer, insulation layer, plastering layer, finishing layer and accessories. The adhesive layer is between the bottom layer and the surface layer. First, the upper and lower layers are firmly bonded together with a cementitious material, and the filler is mainly derived from inorganic substances. Insulation layer In order to avoid and reduce the heat loss of the steam turbine to the environment, the insulation material layer laid on the outer surface of the steam turbine and pipelines is mainly filled with rock wool fibers and a certain amount of organic matter, moisture and adhesives. The finishing layer should be a lightweight functional coating such as finishing mortar, embellishment mortar, or a water-based exterior wall coating with excellent air permeability, so that the phenolic board maintains its lightweight characteristics and increases its aesthetics. The accessories mainly use various kinds of coatings. On the one hand, the color of the surface of the phenolic board is increased, so that it can be applied to any environment, and the coating can play a role in flame retardant and thermal insulation to a certain extent.
Phenolic board has two aspects of anti-combustion performance, one is the ability to prevent the spread of flame, that is, the flame is locally generated by the thermal insulation material, and the flame will not spread and extinguish itself; the other is the thermal insulation performance of the material itself, even if one side of the material catches fire, the other The temperature on one side will not rise high enough to cause the fire to expand. Compared with polystyrene foam and polyurethane foam, it has two characteristics, one is that there is no dripping phenomenon when it is on fire, and the other is that a dense carbon layer is formed on the surface when it is on fire, which prevents the further burning of the foam. The chemical stability of phenolic board is strong. In the construction and use of thermal insulation of equipment and pipelines, organic materials sometimes come into contact with certain solvents and chemicals, so certain properties such as chemical resistance are required. Phenolic foam has better chemical resistance and solvent resistance than other organic foams. It can be used with any water-soluble glue and solvent-based glue in construction, and has a wide range of applications. Phenolic sheet has good thermal stability in a wide temperature range, and its continuous use temperature range is 140-175 °C before shrinkage or cracking occurs, and it has been reported that the irradiation temperature can be as high as 180 °C under discontinuous use. .
The phenolic board does not need to add any flame retardant, and the oxygen index can be as high as 54. The oxygen index of high-density phenolic foam with inorganic fillers can reach 60-70, and the combustion grade can reach Class A. The proportion of carbon atoms in the molecular structure of phenolic resin is high, and the phenol molecule is a good free radical absorbent. In the process of high temperature decomposition , the free radicals generated by the broken methylene bridge are quickly absorbed by phenol molecules, and the tissue reaction continues. When the foam meets fire, the surface can form a "graphite foam" layer of structural carbon, which effectively protects the foam structure in the layer. When one side is on fire, the temperature of the other side will not rise higher, nor will it spread, and when the flame is removed, the fire will automatically go out. Due to the existence of the graphite layer, the surface has no dripping, no curling, no melting phenomenon, and no flame propagation. The density of smoke during combustion does not exceed 5. There are only hydrogen, carbon and oxygen molecules in the phenolic molecules, which decompose at high temperature. Only a product composed of hydrogen, carbon and oxygen can be produced, except for a small amount of CO, there is no other toxic gas, so it is also convenient for firefighters to rescue in the event of a fire.
Phenolic board is made of phenolic foam. Phenolic foam is known as "insulation material" and is a new generation of thermal insulation, fireproof and sound insulation materials. It is lightweight, fireproof, non-combustible in case of open flame, smokeless, non-toxic, non-dropping, and has a wide range of operating temperatures.