Synthesis and Self-Assembly of Amphiphilic Dendrimers Based on Aliphatic Polyether-Type Dendritic Cores
作者:Byoung-Ki Cho、Anurag Jain、Jörg Nieberle、Surbhi Mahajan、Ulrich Wiesner、Sol M. Gruner、Stephan Türk、Hans Joachim Räder
DOI:10.1021/ma035745e
日期:2004.6.1
We have prepared a series of amphiphilic dendrimers with hydrophilic aliphatic polyethertype dendritic core and hydrophobic docosyl peripheries. All dendrimers from first up to fourth generation 1-4 were synthesized in good yield and high purity by a stepwise convergent approach consisting of a combination of Williamson etherification and hydroboration/oxidation steps. Differential scanning calorimetry (DSC) measurements show that the docosyl peripheries melting temperatures and corresponding heats of fusion decrease only slightly with each generation, indicative of a strong segregation between hydrophilic dendritic core and hydrophobic docosyl periphery. The DSC derived docosyl periphery crystallinity shows a gradual reduction with each generation and is corroborated by wide-angle X-ray scattering (WAXS) experiments. Amphiphilic dendrimer self-assembly in the solid state is investigated by small-angle X-ray scattering. Data from 1, 2, and 3 suggest a bilayer lamellar structure with interdigitated dendritic core packing. In contrast, data from 4 are consistent with a 2-dimensional oblique columnar assembly with hydrophilic core structure. The observed thermal and morphological behaviors are rationalized in terms of high incompatibility and intrinsic interfacial curvature between hydrophilic dendritic core and hydrophobic docosyl periphery arising from the unique dendritic molecular architecture.
Poly(oxanorbornenedicarboximide)s dendronized with amphiphilic poly(alkyl ether) dendrons
作者:Xiaoli Liang、Mani K. Sen、Jo-Ann Jee、Oleg Gelman、Jeannette E. Marine、Kenneth Kan、Maya K. Endoh、Deborah A. Barkley、Tadanori Koga、Jonathan G. Rudick
DOI:10.1002/pola.27385
日期:2014.11.15
nanometer‐sized dimensions called dendronized polymers. The structure of these complex molecular architectures is highly tunable and, therefore, of interest for a wide range of potential applications. The first examples of dendronized polymers prepared by living ring‐opening metathesis polymerization of oxanorbornenedicarboximide macromonomers with poly(alkylether) dendrons are reported. Small‐angle X‐ray