Abstract
Poly(vinyl acetate)(PVAc) having low degree of branching of acetyl group lower than one was synthesized by the low temperature-redox emulsion polymerization of vinyl acetate at $0^{\circ}C$. Subsequent saponification yielded high molecular weight poly(vinyl alcohol)(PVA) having number-average degree of polymerization $P_n$ of 4,200. $P_n$ of PVA was constant and independent of the increase of $P_n$ of PVAc contrary to the increase of conversion. Whiteness, syndiotacticity, and crystal melting temperature of PVA increased with a decrease of the polymerization temperature. Syndiotactic triad and diad contents of PVA from PVAc polymerized at $0^{\circ}C$ were 28% and 53%, respectively. Also, crystal melting temperature of PVA from PVAc obtained at $0^{\circ}C$ was 232$^{\circ}C$.