Synthesis, characterization, and fire retardancy of ferrocene containing polyphosphate esters

Abstract

Polyphosphate esters containing ferrocene structures were synthesized from 1,1'-bis (p-hydroxyphenylamido) ferrocene and 1,1'-bis (p-hydroxyphenoxycarbonyl) ferrocene with aryl phosphorodichloridates by interfacial polycondensation using a phase transfer catalyst. The polymers were characterized by infrared, ¹H-, ¹³C-, and ³¹-NMR spectroscopy. The molecular weights were determined by end group analysis using ³¹P-NMR spectral data. The thermal stability and fire retardancy were respectively determined by thermogravimetry and limiting oxygen index (LOI) measurements. The polyamide-phosphate esters showed better thermal stability and higher LOI values than the polyester-phosphate esters.