Phase transfer catalysis in the synthesis of phosphorus-containing polymers

Polyphosphonates of high molecular weights were prepared from chloro- methylphosphonic 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 re- sults (higher inherent viscosities and molecular weights). The polymers were char- acterized by spectroscopic techniques IR and 1 H-NMR. The molecular weights and thermal stability determinations were carried out by gel chromatography and ther- mogravimetry. 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 inher- ent viscosities were obtained at -8 º - 0 ºC, whereas in v-l system the maximum in- herent viscosity was obtained at 120 ºC.