Expanded polystyrene is a rather interesting material.A method of producing was patented in 1928, and has since repeatedly modernized.The main advantage is the low thermal conductivity, and only then at lightweight.Polystyrene foam is widely used in various industries and construction, and each person anyway, faced with the products from it in everyday life.In addition, polystyrene foam, the price of products that are low - be a good option if you want to warm your home.
- What is styrofoam and how is it different from the foam?
- Styrofoam, characteristics and properties
- polystyrene Disadvantages: a review of myths
What is styrofoam and how is it different from the foam?
polystyrene is produced by adding a gas into the polymer mass of polystyrene, which upon subsequent heating significantly increases in volume, filling the entire mold.Depending on the kind of material used to create the different gas volume: for simple v
Quite often, fans tend to call the polystyrene foam and the same material.However, this is not quite true.They have a common basis, but the differences and characteristics are quite substantial.Without going into long spatial considerations, the main characteristics of these are:
- significantly lower foam density, 10 kg per m3, while the polystyrene indicators 40 kg per m3,
- polystyrene does not absorb moisture and vapor,
- look different.The foam - has internal beads styrofoam more uniform,
- foam characterized by a low cost that much when it is used as an insulating material for wall cladding of the building,
- polystyrene has better mechanical strength.
foam produced from polymeric materials which are treated with steam, resulting in greatly increased the amount of pellets.At the same time it leads to the fact that the micropores also increased in size, resulting in a bond between the granules and are gradually deteriorates when exposed to rain and weather conditions, this leads to the fact that the material weakening.Roughly speaking, if you break the foam sheet in half - a large amount of pellets.Styrofoam is not typical, because originally it consists of closed cells, which provide a moisture and vapor permeability of the material.In its early production of pellets at high temperatures to melt to form a uniform fluid mass, and which is filled with gas.
material itself also has several varieties:
- Extruded polystyrene is virtually the same material as the bespressovy, the difference is in the use of equipment such as an extruder, so often extruded and extruded polystyrene is called with the same material.
- extrusion as obtained by processing the final weight of the polymer material, and as a homogeneous mass.The species used for the manufacture of disposable packaging and utensils.Roughly speaking, meat products in supermarkets is Packaged in a package of extruded polystyrene foam.
- Pressing method of obtaining the material is more expensive, as it provides for a subsequent compact foam gas mixture.In this case, it acquires additional strength.
- Autoclave polystyrene is rarely mentioned, and in fact, this kind of extrusion, in which the foaming material and vspekanie made in using the autoclave.
- Bespressovy - one of the most popular varieties.From the granules polistrirola first removed by drying moisture, then foamed at a temperature of 80 ° C, then again subjected to drying and then heated again.The resulting mixture is filled into a form where it is already at the time of self-cooling.This type of polystyrene more fragile, but requires half izopetana for their produce, which affects the final cost.
Styrofoam, characteristics and properties
Styrofoam is a mixed material: someone praises its properties up to heaven, someone on the contrary, vehemently demands the immediate and complete prohibition of its use on the basis of "revelatory workone academician. "However, the ubiquitous Styrofoam and his high popularity inclines towards conclusions that this stuff is really good and has the following advantages:
- low thermal conductivity allows for a significant warming effect.In fact, 11 cm expanded polystyrene are able to provide the same insulation as a wall of sand-lime brick thickness of more than two meters.Indicator thermal conductivity - 0.027 W / mK, which is much lower than that of concrete or brick,
- waterproof material.Even with prolonged exposure to moisture absorption will not exceed 6%, so there is no need to be afraid of deformation structure styrofoam.
- Expanded polystyrene is durable and can withstand up to 60 cycles of exposure to a temperature of -40 to + 40 ° C.Each billing cycle is the climatic year.
- insensitive to the formation of biological media.Styrofoam does not become a breeding ground for fungus and mold.
- harmless material.At its production use non-toxic components, so products from expanded polystyrene used in the food industry.For example, for food storage.
- its light weight polystyrene insulation facades takes much less time and effort than when using other means.
- Fireproof grade material when exposed to an open flame are the property of self-extinguishing and melts without spreading burning.Autoignition temperature of polystyrene component of + 490 ° C, which is almost two times higher than that of wood.In the absence of exposure to more than four seconds to open flame source material polystyrene fades.The thermal energy released during combustion material 7 times less than that of wood.Therefore, polystyrene is not able to maintain the seat of the fire.
- Provide sound insulation.This quality is especially important for residents of typical apartments.A layer of insulating material 3 cm thick enough to reduce the noise level of penetration by 25 dB.
- vapor permeability of the material is at a low mark of 0.05 mg / m * h * Pa, regardless of the extent and density of the foam variety.In fact, water vapor permeability figures are similar to wood cut down a pine or oak.
- Resistant to alcohols and ethers, but is easily susceptible to degradation in contact with the surface of the material with a solvent.
- mechanical tensile strength is not less than 20 MPa.
As seen from the above, EPS is an effective tool for solving many problems: the use of some of its varieties as the packing up of the heat and waterproofing of the facades of buildings.Furthermore, the material used for other purposes in the construction, which will be mentioned hereinafter.
Styrofoam construction used primarily for thermal insulation of the following elements:
- water pipes,
- door and window slopes,
For example, the consumption of polystyrene for insulation of pipes is economically justified and feasible due to its capabilities.Moreover, for these purposes molded polystyrene block, which allows in case of damage to the pipe is easy to access it by removing the desired portion of the protective coating.
Styrofoam actively used for laying transport routes.It reduces the impact load on the vertical coverage in buildings.Distributed in the production of SIP panels.
Scope of polystyrene, the characteristics of which, combined with low cost make it very attractive for use in any industry, virtually unlimited.The only thing that should be considered, the material has a low density, therefore, subject to any mechanical damage.
polystyrene Disadvantages: a review of myths
addition to a bouquet of advantages, there are disadvantages.Moreover, due to polystyrene large variety of myths that need to be considered more:
- Many manufacturers claim that the extrusion foam polystyrene far exceeds the rest of the species in the proof of which often put a table of comparative characteristics of said species than conventional foam.However, the difference in thermal conductivity between the die and extruded polystyrene is almost negligible, and is 0.002 units at the same time as the cost of advertising by extrusion plates for warming up.
- maximum density expanded polystyrene provides the same high performance with insulation.According to experts, such a statement has some differences with reality, as the denser adjacent to each other molecules - the higher the thermal conductivity and the cold easier to get inside.The output of this situation would be the use of polystyrene foam slabs of low density, which must be covered with a reinforcing mesh and a protective layer of primer to improve their mechanical strength.
- Fire resistant polystyrene is absolutely non-flammable and harmless to the human body.Any construction material when exposed to open flame combustion will exhibit properties more or less.However, autoignition temperature in polystyrene is higher than that of wood, and in addition he combustion provides a significantly smaller amount of thermal energy.It is important to remember that the fire-resistant varieties, despite sounding name, was not able to stop the flames, only to reduce its impact.A serious drawback of fire resistant variety compared to conventional carbon dioxide will be used in its manufacture.As a result, at melting the material to give off a far greater amount of harmful substances.Some sellers say flammability based on demonstrative experience: when the basis of a fixed on her plate heater start to warm up on the back side.When exposed to high temperature and melted polystyrene begins to deform, with no fire.Nevertheless, while it is exposed to a flame - the material will continue to burn.
- flame retardants added to the expanded polystyrene for its fire resistance - "in any case, pure poison."Another controversial statement.Flame retardant is a component containing in their structure the substance retarding the combustion process.They differ in composition and contain a variety of components, ranging from formaldehyde, do represent a danger to man and magnesium salts, which are completely harmless and safe.In recent years, are increasingly used solutions based on an inorganic salt, so they can not harm the health.Flame retardants are often used for impregnating and applying a protective layer on the timber to increase its fire resistance.
- Installation polystyrene thermal insulation materials are not capable of providing heat.In fact, the problem of insulation - not to bring the heat and keep it indoors.Roughly speaking, the use of insulation panels will significantly reduce the heat output of the premises, thus, do not have to heat the street at their own expense.
- «Styrofoam hazardous to health."Modern production of the material allows you to create environmentally friendly components, so there is no threat to health.Moreover, the widespread use of semi-finished products for storage and use in the home say just about the safety of the material.
Most problems arise when you want to buy a styrofoam cheaper and low-quality varieties.Insulation plate of a material actually have less strength and are able to begin to deform at a temperature above 40 ° C.The main rule when using materials from expanded polystyrene in any branch of the work will be to ensure the quality and reliability for which you pay.And then during the operation will occur only dignity.