| The term "silicone" was first coined by the German chemist Wohler in 1857. His strategy was based on an organic chemistry nomenclature system. For example, compounds having the empirical formula R2SiO would be named a ketone. Note the "one" suffix, which resulted in silicone. |
Kipping supported this approach to naming organosilicon compounds, even though he admits in his 1912 publication that “…the nomenclature of organic derivatives of silicon has not received much attention, and the names given to such compounds have been chosen rather at random.” He offers in the paper that “the term silicone has already been used to denote the analogues of the ketones and may be advantageously retained for this purpose….”
However, it is important to understand that the chemists of the day all believed that a silicon analog of an organic ketone could be prepared and isolated; making it important that a suitable nomenclature be available when the first example was isolated. Yet, to this day, no one has ever been able to isolate a silicon analog of a ketone.
The issue of organosilicon nomenclature remained in flux until 1949 when the rules of nomenclature recommended by the International Union of Pure and Applied Chemistry (IUPAC) were adopted by the Chemical Society. Today, the IUPAC uses the term “silicone” based upon the SiH2-O- polymer backbone. However, contemporary use of the word “silicone” is not part of their formal nomenclature standards.
The term “silicone” has persisted for more than 140 years and has been liberally applied to describe all organosilicon polymers and even some monomers. There are more than 90 books that have been published with the word “silicone(s)” in their titles. Many of these books include a brief introduction to “silicones,” and a few offer a primer in siloxane nomenclature.
For example, in the forward to the book Silicones and Their Uses, Rob Roy McGregor suggests that “silicones” be defined as “…any synthetic compound containing the elements silicon and oxygen, and organic groups, the silicon being present in sufficient amounts to affect the properties measurably.” This rather soft definition would allow for copolymers of poly(dimethylsiloxane) and organics to be generally termed as silicones. This is not something with which many of today’s scientists would agree.
The most complete introduction to the topic is offered in Organosilicon Compounds, written by Eaborn. This is a key reference that Dow Corning uses for our nomenclature standards.
A shorthand nomenclature is commonly used in the silicon-based-materials industry. "M", "D", "T", and "Q" are used to describe complicated siloxane building blocks.
Sources:
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A. Lee Smith (ed), Analysis of Silicones, John Wiley and Sons, New York (1974).
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F.S. Kipping, “Organic Derivatives of Silicon. Part XV The Nomenclature of Organic Silicon Compounds,” J. Chem. Soc., 101, 2106 (1912).
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C.R. 15th Conf., IUPAC, 127-132 (1949).
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“Editorial Report on Nomenclature,” J. Chem. Soc., 5064 (1952).
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Rob Roy McGregor, Silicones and Their Uses, McGraw-Hill, New York (1954).
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C. Eaborn, Organosilicon Compounds, Butterworths, London (1960).
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Lane and Burns, Immunology of Silicones, Potter & Rose (eds), Springer-Verlag, Berlin (1996).
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Allen, Kochs, and Chandra, “Industrial Organosilicon Materials, Their Environmental Entry and Predicted Fate,” in Organosilicon Materials, Chandra (ed), Springer-Verlag, Berlin, p3-10 (1997).
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M. Brook, Silicon in Organic, Organometallic and Polymer Chemistry, John Wiley and Sons, New York (2000).
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