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It is shown that freshly prepared, filtered, blue solutions of potassium in 1,2‐dimethoxyethane (DME) or in tetrahydrofuran (THF) initiate the rapid polymerization of styrene. For the K—DME system 100% yields of living polymer are obtained, whereas for the K—THF system, fractional yields of nonliving polymer are formed. By the application of rapid mixing and quenching techniques, minimum values of the rate constant of anionic propagation are obtained for the K—DME system at —78, 0, and 25°C. and for the K—naphthalene—THF system at 0°C. The true initiator in these blue solutions is considered to be a solvated, spin‐coupled, electron pair. The difference between the two systems and the probable kp values are discussed.

Polymeric films deposited from the vapor of C&16 by the surface-photopolymerization technique are electrically and mechanically continuous on various substrates when very thin. The thickness of the films depends upon irradiation time with wavelengths in the region 2000-3000A. Re-irradiation in oxygen (air) of the polymeric films with light of these low wavelengths leads to patterned removal of the films. Since films 500A thick and less can resist etchants for various substrates, a new and extremely thin positive photoresist system is possible. Resolution of etched substrates to lines a few microns wide has been demonstrated. If the polymeric films from C4C16 are deposited from the monomeric vapor at lower substrate temperatures they are soluble in various solvents. Reirradiation with UV light with the films in vacuum produces a patterned fixing of the polymer with respect to acetone. A negative photoresist system is therefore possible. Again, films of thickness 500A and less can resist various etchants such that substrates can be etched to high resolution.

Physical properties of injection molded, massgranulated composites of poly (buteneterephthalate), modiJied PPO, andpoly carbonatelPBT blends, reinforced with 30% by weight of Suzorite mica 60s were evaluated after compounding in the K-mixer and in a single-screw Killion extruder under a mnge of '