Phosphonoethylated polyglycidols as building blocks for multifunctional polyethers

The present work deals with the preparation and characterization of multifunctional polyglycidols, which are functionalized with phosphonate and phosphonic acid groups. Phosphorus-containing polymers are interesting for surface coatings as well as for the design of biomaterials and flame retardant additives. Polyglycidols stand out due to their hydrophilicity, high functionality and biocompatibility. Thus, the aspiration of this work was to combine the beneficial properties of both polymer classes. This enables access to tailor-made polymers for different applications in the abovementioned fields. The binding of phosphonate groups to polyglycidol was achieved by oxa-Michael addition of polyglycidol´s hydroxymethyl groups to diethyl vinylphosphonate as the key step for the preparation of partly phosphonoethylated polyglycidols. This reaction has not yet been applied for the covalent attachment of phosphonate groups to hydroxyl-functional polymers. The influence of the reaction conditions on the selectivity of the reaction has been studied in detail. Application of the optimized reaction conditions allowed the preparation of partly phosphonoethylated polyglycidols with up to 70% of phosphonate residues. The corresponding phosphonic acid-containing analoga were obtained through subsequent dealkylation of the phosphonate groups with bromotrimethylsilane. After establishing the synthetic route and characterization of the polymers, the remaining OH-groups at the polyglycidol backbone are exploited for targeted modifications to make phosphonate-functionalized polyglycidols attractive for potential applications.