Enzymatic ring-opening polymerization of ethylene alkyl phosphates

Enzymatic ring-opening polymerization of cyclic phosphate was achieved in this study. NMR spectra experiments showed that the polyphosphate prepared by CL-catalyzed ring-opening polymerization had hydroxy and phosphoric acid end-groups at both termini. The influence of different reaction factors such as reaction temperature, enzyme concentration and polymerization time was studied. Six phosphates with different alkyl groups were polymerized in bulk by using three different enzymes. The result indicated that the length of alkyl groups made no marked influence on D_p but affected the yield greatly. The longer the length of alkyl groups, the stronger the lipophilicity of the polyphosphates is. Porcine pancreas lipase (PPL) and Candida rugosa lipase (CL) exhibited better activity than akaline phosphatase (AP) in this polymerization reaction.