Phase transfer catalysis in the synthesis of phosphorus-containing polymers

Polyphosphonates of high molecular weights were prepared from chloromethylphosphonic dichloride (CMPD) and 4,4’-sulfonyldiphenol (SDP) by two-phase interfacial polycondensation (l–l), in an organic solvent-aqueous alkaline solution system, with a phase-transfer catalyst, at –8 º – 0 ºC. Alternative method, namely vapor-liquid interfacial polycondensation (v–l) of the same reagents gave better results (higher inherent viscosities and molecular weights). The polymers were characterized by spectroscopic techniques IR and 1H-NMR. The molecular weights and thermal stability determinations were carried out by gel chromatography and thermogravimetry. The effect of reaction temperature on yield and inherent viscosity in l–l and v–l interfacial polycondensation was studied. In l–l system the highest inherent viscosities were obtained at –8 º – 0 ºC, whereas in v–l system the maximum inherent viscosity was obtained at 120 ºC.