Polyamides containing phosphorus. I. Preparation and properties

This study has for the first time provided a series of high molecular weight polymers having trivalent phosphorus in the backbone structure (as phosphine‐containing polyamides) and has extended the series of phosphine oxide polyamides beyond the previously disclosed bis(carboxyphenyl)phosphine oxide types. It was found that bulk polymerization rather than solution or interfacial procedures was the preferred method of preparing these materials. The phosphorus polyamides generally were found to be amorphous, relatively low softening materials having an extended solubility range. Most polyamides containing trivalent phosphorus slowly degrade in formic acid solution. A comparison of the thermal stability, adhesive bond strengths, and mechanical behavior of typical polyamides containing phosphine or phosphine oxide groups in their backbone structure to those of analogous regular nylons disclosed no major differences.