The key difference between soda lime glass and borosilicate glass is that the soda lime glass does not contain boron-derived constituents whereas the borosilicate glass contains boron trioxide as the main glass-forming constituent. Because of their chemical composition, the borosilicate glass is more resistant to thermal shock than the soda lime glass, which has a low thermal resistance.
The glass is an amorphous (non-crystalline) solid that we use in our day to day life. It is a solid that is transparent and contains mainly silica. In fact, the oldest version is silicate glass. It contains silicon dioxide as the major constituent. People have now found many different forms of glass that have improved properties for desired applications. Soda lime glass and borosilicate glass are such two forms.
What is Soda Lime Glass?
Soda lime glass is the most common form of glass that mainly contains silicon dioxide. This form of glass is relatively inexpensive and chemically stable. Moreover, it has a considerable hardness with extreme workability. More importantly, we can re-soften and re-melt this glass several times via glass recycling. Therefore, we can use it many times.
The raw materials that we can use to make this glass are sodium carbonate, lime, dolomite, silicon dioxide, aluminium oxide, etc. In the production process, we can use the raw material in a glass furnace. The furnace should be at temperatures locally up to 1675 °C. The type of raw material we use has a great influence on the colour of the glass. For example, we can obtain green and brown bottles using raw material, which consists of iron oxide.
When considering the chemical and physical properties of soda lime glass, it can undergo a steady increase in its viscosity upon decreasing temperature. Moreover, the glass is readily formable to obtain desired shapes when the viscosity is very high. There are two types as container glass and flat glass according to the applications.
What is Borosilicate Glass?
Borosilicate glass is a form of glass that contains silicon dioxide and boron trioxide. These two chemical compounds act as the major glass-forming constituents. The characteristic feature of this form of glass is the very low coefficient of thermal expansion. This makes the glass resistant to thermal shock. Therefore, we can use this glass to produce reagent bottles and bakeware mainly.
The raw material for the production of this glass is a boric oxide, silica sand, soda ash and alumina. We need to combine them via melting. There are several forms of this glass depending on the raw material that we use in its production; non-alkaline-earth borosilicate glass, alkaline-earth containing borosilicate glass and high borate borosilicate glass.
What is the Difference Between Soda Lime Glass and Borosilicate Glass?
Soda lime glass is the most common form of glass which mainly contains silicon dioxide whereas the borosilicate glass is a form of glass that contains silicon dioxide and boron trioxide. They differ from each other according to the chemical composition. Thus, the soda lime glass contains mainly silica, and there are no boron-containing compounds while the borosilicate glass mainly contains silica and boron trioxide. This is the key difference between soda lime glass and borosilicate glass.
Moreover, the raw materials that we use to make soda lime glass are sodium carbonate, lime, dolomite, silicon dioxide, aluminium oxide, etc. while the raw material for the production of borosilicate glass are boric oxide, silica sand, soda ash and alumina. Another significant difference between soda lime glass and borosilicate glass is their thermal resistance. The thermal resistance of soda lime glass is low compared to borosilicate glass, which has a very low coefficient of thermal expansion; therefore, it is resistant to thermal shock. Thus, the thermal resistance determines the applications of each type of glass.
The below infographic shows a more detailed comparison on the difference between soda lime glass and borosilicate glass.
Summary – Soda Lime Glass vs Borosilicate Glass
The glass is very useful for us in our household as well as for laboratory and industrial applications. Soda lime and borosilicate glass are two types of glass. The key difference between soda lime glass and borosilicate glass is that the soda lime glass does not contain boron-derived constituents whereas the borosilicate glass contains boron trioxide as the main glass-forming constituent.
1. “Soda–Lime Glass.” Wikipedia, Wikimedia Foundation, 29 Aug. 2018. Available here