SYNTHESIS AND CHARACTERIZATION OF CORE-CONTANING HYPERBRANCHED POLYACETALS WITH HYDROLYSABLE BACKBONE

Core-containing backbone hydrolysable hyperbranched polyacetals (HBPAs) were synthesized via the transacetalization polymerization process between a AB2 type monomer (2-(4-(dimethoxymethyl)-phenoxy) ethanol) and a B2 type core (benzaldehyde dimethyl acetal). By continuously removing the alcohol with lower boiling point, the reaction moves toward the direction of polymerization. The molecular weight and polydispersity could be modulated by varying the core feed ratio. Higher core feed ratio led to lower molecular weight and polydispersity. Under weak acidic conditions,the backbone of the polymer broke down and yielded 4-(2-hydroxyethoxy)-benzaldehyde as the final degradation product. The experiments showed that their hydrolysis rates were also obviously affected by the core content in the hyperbranched polyacetals. Increasing core feed ratio can accelerate the hydrolysis rate. By introducing core molecules,the structure and properties of hyperbranched polyacetals can be controlled to a certain extent.