Borates are an important ingredient in fiberglass insulation, which represents the main use of borates worldwide. Fiberglass insulation is also known as mineral wool or glass wool.
Fiberglass is used for thermal and acoustic insulation, with great use in the thermal insulation of residential and commercial buildings. Here it plays an important role in reducing energy use and carbon dioxide emissions from the built environment.
In buildings, fiberglass insulation can be used in the form of fill blankets (rolls), batts (pre-cut slabs), or loose (blown wool). Smaller uses for fiberglass insulation include duct and pipe wrapping for refrigeration, heating, ventilation, and air conditioning systems.
Fiberglass produces insulation by trapping air within its mesh of fibers to reduce the rate of heat transfer.
The most important role of boron in glass fibers is that it increases the absorption of infrared radiation, which significantly increases the effectiveness of the insulation of the roll, or wool batt.
In fiberglass manufacturing, borates act as a powerful flux that lowers the melting temperature of glass batches. They also control the relationship between temperature, melt viscosity and glass fiber formation surface tension to optimize the process. The end result is short, strong fibers that are bio-soluble (dissolves in the lung if inhaled during installation), and resistant to water and chemical attack.