Synthesis and characterization of poly(phosphon acetal) derivatives of poly(vinyl alcohol)

Preparation of poly(phosphonoacetals) (PPA) by transacetalation of poly(vinyl alcohol) with diethyl-phosphonoacetal is described. PPA with a degree of substitution of 60% is an alcoholsoluble polymer with a glass transition temperature (T_g) of 67°C. High resolution ¹H and ¹³C NMR spectra reveal the presence of hemiacetals alongside the six-membered acetal ring with an approximate ratio of 2:8 of these substituents. A possible correlation between the microtacticity of the parent PVA and the structure of PPA is indicated; the syndiotactic and isotactic sequences on the parent polymer controls the relationship between the two pendant groups.