Silicones: New Silica‐based Plastics of Interest to the Ceramic Industry *

Abstract

Silicones derive many of their most useful properties from the inorganic nature of the silicon-to-oxygen links which they possess in common with glass and mineral silicates. They derive plasticity, solubility, and water repellency from the organic radicals attached to their basic structures. The chemical nature of silicon in combination with oxygen permits the development of a variety of silicone compounds in various physical forms ranging from fluids through gels and resins to elastic materials. Because of their ease of application, their general heat stability, and chemical inertness, they are natural complements to ceramic bodies in many applications. They are already proving their usefulness with these materials in the production of new types of electrical insulation, in the surface treatment of glass and ceramic products, and as auxiliary dielectrics for use with ceramic insulating forms.

Dielectric constants of dimethyl siloxane polymers

“…From the dielectric constant and density data as a function of temperature it is possible to compute the dipole moments, the infrared dispersion, and the various contributions to the polarization by means of the Onsager-Kirkwood (9,10) theory. The relation between the dipole moment, µ , and the absolute temperature, T is given by them as 4,tN 9kT 0µ1 = M (e d -n8)(2e + n2) t(n2 + 2)8 (2) where N is Avagadro's number; k is Boltzmann's constant, g is a factor depending upon the coordination of the neighboring molecules immediately surrounding a given molecule of the substance (g = 1 for completely uniform surroundings, reducing this equation to Onsager's); e is the dielectric constant at low frequency; and n is the refractive index-at infinite frequency if there is no infrared dispersion, or n, at a frequency between dipole dispersion and infrared dispersion, if there is.…”

Frederic Stanley Kipping—Pioneer in Silicon Chemistry: His Life & Legacy

“…Kipping built on his interest in stereochemistry of non-carbon centres, especially tetravalent nitrogen compounds with a number of papers in the period 1900-1905. He then turned his attention to the preparation of asymmetric silicon compounds, typically preparing aryl containing chiral silicon compounds and the converting them to their sulphonic 1 For a semi-fictionalised account of the lives of the Holland sisters see [14]. acids so that they could be resolved by crystallisation with the single enantiomer of a nitrogen containing cationic natural product such as brucine (Scheme 3).…”