Infrared spectroscopy studies were undertaken to determine the effects of ultraviolet light radiation on a methylsiloxane resin. The results indicate that SiCH2Si linkages were formed as a result of irradiation at wavelengths above 281 mμ from a xenon are lamp; on the other hand, SiOH and SiCH2CH2Si linkages were formed instead when the resin was exposed to the lower wavelengths emitted from a mercury vapor lamp. The different effects on the resin induced by the two ultraviolet light sources are attributed to the fact that only the energies from the mercury vapor lamp radiation are sufficient to cause the excitation of oxygen molecules in the air surrounding the irradiated polymer. The excited oxygen molecules prevented the formation of SiCH2Si structures by interacting with active %tbond;Si units that were formed as a result of SiC bond rupture to produce SiOH; SiCH2CH2Si linkages were formed as the result of a secondary reaction.

This study reports the synthesis of new silicon‐containing amide, benzimidazole hydrazide, and oxadiazole polymers. Procedures are described for the preparation of several intermediate compounds. The silicon‐containing polymers are soluble in organic solvents. Solution‐cast films from the polymers generally are flexible and exhibit good adhesion to glass and metal surfaces. Preliminary examination indicates that the polymers are heat‐stable at elevated temperatures.

These studies were undertaken to determine the thermal behavior of structurally related polymers having a carborane nucleus in the recurring unit. Three of these products also contained phthalocyanine rings in their molecules. Results of thermal analysis studies show generally that the relative heat stability of the polymers conforms closely with indications given by similar investigations of structurally related intermediate and model compounds. A polymer with dimethylsiloxane units exhibited more resistance to thermal decomposition than similar products having urethane groups in their molecules. The urethane polymers derived from tolylene diisocyanate were found to be somewhat less heat‐stable than analogous materials synthesized from methylenebis‐(p‐phenyl isocyanate). The relative order of thermal resistance of these materials follows that of more conventional polyurethane elastomers.

The effects of incorporating a p‐phenylene‐ (or m‐phenylene)‐1,3,4‐oxadiazole fragment into the backbone of poly[1,4‐phenylene(diphenylsilyl)‐1,4‐phenylene‐2,5‐(1,3,4‐oxadiazole)], which was developed by the authors, was investigated. Bis[(p‐carbohydrazidophenyl)]diphenylsilane was copolymerized with dipentachlorophenyl terephthalate or isophthalate to produce the prepolymers poly[N‐(p‐diphenylsilylbenzoyl)‐N′N″‐(terephthaloyl)‐N″′‐(p‐benzoyl)dihydrazide] and poly[N‐(p‐diphenylsilylbenzoyl)‐N′,‐N″‐(isophthaloyl)‐N″′‐p‐(benzoyl) dihydrazide], respectively. The polyhydrazides were converted by thermal dehydration into poly[1,4‐phenylene(diphenylsilyl)‐1,4‐phenylene‐(1,3,4‐oxadiazole‐2,5‐diyl)‐1,4‐phenylene‐2,5‐(1,3,4‐oxadiazole)] and poly[1,4‐phenyl‐ene(diphenylsilyl)‐1,4‐phenylene‐(1,3,4‐oxadiazole‐2,5‐diyl)‐1,3,4‐(oxadiazole)]. The new polymers were soluble in organic solvents. Films cast from these solutions exhibited good adhesion to glass and metal surfaces. Thermal analysis showed that the heat stability of all these polymers was about the same and that they were resistant to decomposition when heated in air to about 400°C. The results also indicated that these polymers were somewhat less heat‐resistant than samples of poly‐[1,4‐phenylene(diphenylsilyl)‐1,4‐phenylene‐2,5‐]1,3,4‐(oxadiazole) synthesized from bis(p‐carbohydrazidophenyl)diphenylsilane and bis‐(p‐carbopentachlorophenoxy‐phenyl)diphenylsilane.

The reaction mechanism of the ozone attack of SBR copolymers was studied to obtain information for use in the development of elastomeric materials having improved resistance to deterioration in service. Techniques of ultracentrifugation and viscometry were utilized to follow molecular changes induced by ozone. Chemical changes were investigated by measuring variations in active oxygen group concentration. Results suggest that the autocatalytic degradation of uninhibited SBR was initiated by a random ozone attack at a double bond on the unozonized chain, producing an ozonide which decomposed spontaneously, forming small segments with activated chain‐ends. This primary reaction, in the presence of oxygen, activated an α‐methylenic chain cleavage process which was terminated when the molecules were degraded to a limiting size, where no more R. radicals were formed from α‐methylenic groups. The reaction was also terminated when oxygen was removed from the system.