6533b824fe1ef96bd1280a37

RESEARCH PRODUCT

Linear-dendritic nonionic poly(propylene oxide)–polyglycerol surfactants

Holger KautzRolf SchubertYong-keun KimHolger FreyVladislav Istratov

subject

chemistry.chemical_classificationOrganic ChemistryGlycidolGeneral MedicineBiochemistrychemistry.chemical_compoundchemistryPulmonary surfactantPolymerizationCritical micelle concentrationDrug DiscoveryAmphiphilePolymer chemistryCopolymerPropylene oxideAlkyl

description

Abstract A new type of linear-hyperbranched surfactant has been prepared by anionic ring-opening multibranching polymerization of glycidol onto an end-functional poly(propylene oxide) (PPO) macroinitiator. A hyperbranched, highly hydrophilic polyglycerol block is obtained as the polar segment of the structure. Molecular weights of the nonionic amphiphiles obtained were in the range of 390 to 8,600 g/mol. For comparison, initiators bearing a C16 alkyl chain have also been employed. Furthermore, hyperbranched polyglycerol homopolymers were investigated with respect to amphiphilic properties. All linear-dendritic amphiphiles have been characterized by SEC, DSC, 13 C and 1 H NMR spectroscopy. A fluorescence-probe technique based on diphenyl hexatriene (DPH) as probe molecule was employed to determine the CMC (critical micelle concentration) of the samples in water. CMCs varied from 7.5×10 −6 to 1.7×10 −3  M and were found to depend on the copolymer architecture and the hydrophilic/hydrophobic balance. Measurements at pH 6.75 and 3.00 revealed an increase of the CMC by a factor of 10 for the amine containing copolymers upon lowering of the pH.

https://doi.org/10.1016/s0040-4020(03)00470-8