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Cyclic structures in conventional organic chemistry have been well established. Early workers thought only five and siR membered carbon rings were possible, but it was later shown1 that strained rings of three and four members could exist.Continued studies with cyclic hydro-carbons2 led to the preparation of much larger unstrained rings containing up to eighteen carbon atoms.Carothers and Hill3 believed all the larger rings may not be entirely without strain, but they pointed out the effect of oxygen in the ring as a means of reducing strain.Cyclic structures have also been shown to exist in inorganic chemical systems. Particularly in the field of mineral silicates, Bragg4 has shown by X-ray analysis, cyclic structures containing six, * The material contained In this paper was presented in large part before the

Gehman cold‐flex, volume‐temperature, and stress‐temperature studies were used to investigate the low‐temperature characteristics of polysiloxane copolymers with respect to copolymer composition. A complete range of phenyl methyl‐dimethyl siloxane copolymers were examined as elastomeric compounds. Like other copolymers, the stiffening temperature was dependent upon the composition of the copolymer. Stiffening of the elastomers was due to crystallization in some cases and second‐order transition in others. Copolymers having either low or high amounts of PhMeSO stiffened because of crystallization, while copolymers of intermediate composition (7.5 to 15 mole‐% PhMeSiO) stiffened because of nearness to their respective second‐order transition temperatures. Second‐order transition temperature increased with the PhMeSiO content. For those siloxane polymers and copolymers that crystallized, the process was rapid when compared with crystallization behavior of other polymer systems. Only one minimum low‐temperature stiffening point was found in the phenyl methyl‐dimethyl siloxane copolymer system. The unique low‐temperature characteristics of polysiloxane elastomers are explainable on the basis of three factors. These are: (a) very flexible molecules, (b) low temperature coefficient of viscosity over a broad temperature range including low temperatures, and (c) copolymerizability of dimethyl siloxane with other siloxanes containing bulky pendant groups which lower the stiffening temperature.

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Electrochemical copolymerization of pyrrole and 3-(6-ferrocenyl-6-hydroxyhexyl)pyrrole yields a ferrocene functionalized polypyrrole with a controllable amount of ferrocene functionalization.Conducting polypyrrole can be chemically modified to produce films with a wide variety of highly specific electroactive properties by attaching substituents to the pyrrole monomer prior to polymerizationl--" or to polypyrrole films,h or by incorporating electroactive and electro-optic molecules as B r