The key difference between silane and siloxane is that silane is a chemical compound while siloxane is a functional group in organosilicon.
Silane and siloxane are silicone-containing compounds. Both these materials are important as sealers. Here, silane sealer tends to penetrate deep for below surface protection while siloxane sealer works on the surface for water repellency.
CONTENTS
1. Overview and Key Difference
2. What is Silane
3. What is Siloxane
4. Side by Side Comparison – Silane vs Siloxane in Tabular Form
5. Summary
What is Silane?
Silane is an inorganic compound having the chemical formula SiH4. It is a group 14 hydride. Further, this substance occurs as a colourless gas having a repulsive odour. The odour is similar to the odour of acetic acid. Its molar mass is 32.11 g/mol. Also, the most common commercial-scale route for the production of silane is the reaction of hydrogen chloride with magnesium silicide.
Figure 01: Structure of Silane Molecule
The shape of the silane molecule is tetrahedral, similar to methane molecule. Because of the great difference between the electronegativity values of silicone and hydrogen, it has an opposite polarity to that of methane. Due to this reversed polarity, silane can form complexes with transition metals. Moreover, silane can undergo spontaneous combustion in air. That means; it doesn’t require any external ignition source. Furthermore, the dominant application of silane is as a precursor for the production of elemental silicon. This is important in semiconductor production. It is also useful as a sealer.
What is Siloxane?
Siloxane is a functional group having the Si-O-Si linkage. The functional group is present in organosilicon compounds. The siloxane compounds can be either straight-chain compounds or branched compounds. These linkages form the backbone of the silicone polymer, i.e. polydimethylsiloxane.
Figure 02: Siloxane Linkage
Furthermore, the major route of forming a siloxane linkage is by condensation of two silanols. We can produce silanol by hydrolysis of silyl chloride. This compound is also important in making silicon carbide upon ignition in an inert atmosphere. Moreover, siloxane polymers are useful as sealers for waterproofing surfaces.
What is the Difference Between Silane and Siloxane?
Silane is an inorganic compound having the chemical formula SiH4 while Siloxane is a functional group having the Si-O-Si linkage. The key difference between silane and siloxane is that silane is a chemical compound while siloxane is a functional group in organosilicon. Further, the dominant application of Silane is using it as a precursor for the production of elemental silicon, while siloxane is important in making silicon carbide.
Below infographic shows more comparisons related to the difference between silane and siloxane.
Summary – Silane vs Siloxane
Silane is an inorganic compound having the chemical formula SiH4 while Siloxane is a functional group having the Si-O-Si linkage. The key difference between silane and siloxane is that silane is a chemical compound while siloxane is a functional group in organosilicon.
Reference:
1. “Silane.” National Center for Biotechnology Information. PubChem Compound Database, U.S. National Library of Medicine, Available here.
2. Tilley, Sloane K., and Rebecca C. Fry. “Priority Environmental Contaminants.” Systems Biology in Toxicology and Environmental Health, 2015, pp. 117–169., doi:10.1016/b978-0-12-801564-3.00006-7.
Image Courtesy:
1. “Silane-2D” (Public Domain) via Commons Wikimedia
2. “SiloxaneFxnlGp” By Smokefoot – Own work (CC BY-SA 3.0) via Commons Wikimedia