Two Dimensional Aggregation Behaviors of Quinoxaline Dendrimers.
This study focuses on the molecular behavior of two dendrimers containing a hydrophilic core group (carboxyl group) and hydrophobic branches (quinoxaline and methoxyphenyl groups), 2,3-bis(4-(2,3- bis(4-methoxyphenyl)quinoxalin-6-yloxy)phenyl)quinoxaline-6-carb-oxylic acid (G2) and 2,3-bis(4-(2,3-bis(4-(2,3-bis(4-methoxyphenyl)quinoxalin-6-yloxy)phe-nyl)quinoxalin-6-y-oxy)phenyl) quin oxaline-6-carboxylic acid (G3) at the air-water interface. To understand the mechanism of the self-assembly of these molecules, we measured the surface pressure-area (III-A) isotherm and investigated the surface morphology of Langmuir-Blodgett films transferred onto hydrophilic silicon wafers using atomic force microscopy (AFM). Upon compression, G2 molecules stand up and steadily make close-packed monolayer whereas G3 molecules form circular domains and gradually make aggregates of domains. These results were confirmed by the X-ray Reflectivity (XRR) profiles of G2 and G3 monolayers transferred onto silicon substrates.
Soyoung
S
Choi
Hoik
H
Lee
Hwan Kyu
HK
Kim
Sang Uck
SU
Lee
Daewon
D
Sohn
D050091:Dendrimers / Q000737:chemistry*; D046911:Macromolecular Substances; D008422:Materials Testing; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure*; D010316:Particle Size; D011312:Pressure; D011810:Quinoxalines / Q000737:chemistry*; D013499:Surface Properties; D013501:Surface-Active Agents / Q000737:chemistry*; D014867:Water / Q000737:chemistry*
D050091:Dendrimers; D046911:Macromolecular Substances; D011810:Quinoxalines; D013501:Surface-Active Agents; D014867:Water