Glass wool is an inexpensive and effective insulation. In terms of popularity, it is second only to mineral wool and foam. Glass wool fibers are much longer than any other fiber material. This feature is due to the way it is produced.
Glass wool, used today as a thermal insulator, is very different from a similar product that was used to insulate pipes and houses in the last century. That glass wool was made from broken glass, the current one - from quartz sand. Therefore, these materials differ both in appearance and in properties.
What is glass wool made of?
The composition of modern glass wool includes limestone, soda, ethybor (another name is borax), dolomite. The presence of borax provides a deterrent to rodents, ants and cockroaches. In the past, phenols and formaldehyde were added to the glass wool process to preserve the fibers. Today they are excluded from the list of constituents, as it became known that these substances have a harmful effect on human health.
How is glass wool made?
Glass wool is a fibrous material for which different raw materials are used. Most often it is quartz sand, but there are technologies for making this material from kaolin, glass industry waste, graphite.
The method of producing glass wool is blown-and-blow. Due to this, the fibers of the insulation are longer and at least twice as thick (16-20 microns) than that of mineral, stone or basalt wool. This feature makes glass wool the most elastic and vibration-resistant material of all fiber insulation materials. All this in combination with a low specific weight makes this product easy to install, durable and safe to use.
The glass wool production process is as follows: quartz sand (broken glass, graphite) is melted to a temperature of 1000 ° C, soda, borax and other components are added, and placed in a special centrifuge. When it starts to rotate, long thin fibers are formed under the influence of centrifugal forces. They are treated with an aldehyde-based polymer composition, which gives their structure greater strength.
As a result of this process, a material is obtained consisting of a plurality of tightly fitting fine fibers. But despite this, glass wool is quite elastic and keeps its shape well. The strength of the fibers is 20-25 MPa. The thermal conductivity of the material is 0.03-0.052 W / mK. Temperature resistance - 450 nC.
Fiberglass products can be rigid or semi-rigid. They are used in construction to insulate various structures and pipelines. The largest producers of glass wool are Fleiderer (Chudovo, Russia) and Isover (Finland).