THERMAL POLYMERIZATION OF DIPHOSPHINE-4

The pyrolysis of diphosphine-4 has been examined in static reactors over the temperature range 300-830°K and reactant pressure range 0.5-10 Torr. Both the loss of diphosphine-4 and the formation of phosphine were observed as a function of time. At the lower temperatures, the formation and subsequent decay of triphosphine-5 was measured, while at the higher temperatures tetraatomic phosphorus was a minor product. The overall reaction is controlled by the nature of the surface, but the role of the surface is not simply to provide catalytic sites. It has been shown by labeling studies that the solid formed on the surface during the reaction is a labile hydride and that this hydride reacts directly with diphosphine-4. In addition, there appears to be a dynamic equilibrium set up between the gas-phase hydrides and the polymeric surface hydride. The entire complex reaction may be explained in terms of two simple generalized reactions. © 1969, American Chemical Society. All rights reserved.