Synthesis, characterization, and thermal studies of cardanol‐based polyphosphate esters

Polyphosphate esters were synthesized from derivatives of cardanol phosphorodichloridateates and dihydric phenols by interfacial polycondensation using a phase transfer catalyst. The polymers were characterized by IR, 1H‐, 13C‐, and 31P‐NMR spectroscopy, and GPC. The thermal stability and thermal degradation kinetics of the polymers were determined by thermogravimetry. The flammability of the polymers was evaluated by limiting oxygen index values.