Arylene ether phosphine oxide homopolymers were prepared via nucleophilic aromatic substitution polycondensations of bis(4-ftuorophenyl)phenyl (or methyl) phosphine oxide with various aromatic bisphenols in the presence of a weak base and an aprotic dipolar solvent. These thermoplastic materials with Tg values in the range of about 200°C-285°C showed 5% weight loss in air around 500°C with substantial amounts of char yield at 800°C, which was related to their excellent' self-extinguishing characteristics relative to other engineering thermoplastics. Additionally, the presence of phosphorus in the char after such high temperature heating implied that these materials should also be resistant to aggressive oxygen plasma environments. Indeed, these systems showed extremely low amounts of etching in oxygen plasma when compared with other engineering polymers. The presence of phosphorus residues after either burning or etching with oxygen plasma could play crucial roles in areas of commercial importance and aerospace applications.

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Several thermoplastic and thermosetting polymeric materials containing the phenyl phosphine oxide group were prepared and characterized by physical methods. High molecular weight poly(arylene ether)s and polyimides containing the hydrolytically stable bulky phosphine oxide unit were synthesized and found to be soluble materials with moderately high glass transition temperatures. The phenyl phosphine oxide moiety was further incorporated into epoxy and bismaleimide type crosslinked systems. Phosphorus promoted char formation in air was displayed by both the linear and crosslinked macromolecules, leading to improved self‐extinguishability relative to the non‐phosphorus containing analogous polymeric systems.

As part of our studies directed at new treatments for cyanide poisoning we examined the effect of temperature on both the non‐catalyzed and the albumin‐catalyzed reactions of cyanide with a colloidal suspension of elemental sulfur (CSES). Using saturated sulfur solutions prepared in two solvents, pyridine (PY) and methyl cellosolve (MC), the reactions were studied at 15.0, 25.0, 30.0 and 37.5°C. For all the cyanolysis reactions (non‐catalyzed and albumin‐catalyzed) there is an enhancement of reaction rate when the organic solvent for the sulfur is MC. Irrespective of the solvent for the CSES, the non‐catalyzed reactions gave linear Arrhenius plots (PY, correlation coefficient = 0.998; MC, correlation coefficient = 0.997). In each case the entropy of activation was positive (14.1 cal K−1 mol−1 for PY and 56.4 cal K−1 mol−1 for MC). In contrast with these results the albumin‐catalyzed reactions generated non‐linear Arrhenius plots and negative entropies of activation. Non‐linear plots were observed with the three albumins studied: human serum albumin, heat‐shock bovine serum albumin and fatty acid‐free bovine serum albumin. The non‐linear plots are the result of a more complex reaction sequence than a simple cyanolysis reaction.

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