Synthesis, Characterization and Hydrolytic Degradation of p-Cresol-Substituted Polyphosphazenes

Abstract

Two polymers poly[bis(p-Cresol)phosphazenes] (PBPP) and poly[bis(p-cresoldiethyl amino)phosphazenes] (PBPDEAP) were synthesized, characterized and subjected to hydrolytic degradation and investigated in vitro degradation for drug delivery. The syntheses were carried out by thermal ring-opening polymerization followed by chlorine replacement via macromolecular substitution reaction. The polymeric products were characterized by FTIR, 1H NMR, thermal analysis (DSC), elemental analysis and gel permeation chromatography (GPC) analysis. Hydrolytic degradation was observed by percentage weight loss in buffer solutions of a broad pH range (4.5–10) in deionized water at body temperature (37 °C). It was found that PBPDEAP degraded more rapidly than PBPP, and hydrolytic degradation mechanism was proposed. It was found that PBPP and PBPDEAP are biodegradable, biocompatible and non-toxic and can be tailored for in vitro and later in vivo studies.