Photoelectron spectroscopy studies of the functionalization of a silicon surface with a phosphorylcholine-terminated polymer grafted onto (3-aminopropyl)trimethoxysilane.
The structure of a biomimetic phosphorylcholine (PC)-functionalized poly(trimethylene carbonate) (PC-PTMC-PC), linked to a silicon substrate through an aminolysis reaction at 120 degrees C with (3-aminopropyl)trimethoxysilane (APTMS), was studied using photoelectron spectroscopy. Two chemical states were found for the unreacted APTMS amine, a neutral state and a protonated state, where the protonated amine on average was situated closer to the silicon substrate than the neutral amine. The experiments also indicated the presence of a third chemical state, where amines interact with unreacted silanol groups. The PTMC chains of the grafted films were found to consist of only 2-3 repeat units, with the grafted chains enriched in the zwitterionic end group, suggesting that these groups are attracted to the surface. This was further supported by the experiments showing that the PC groups were situated deeper within the film.
Kristensen
Emma M E
EM
Department of Physics, Box 530, and Department of Materials Chemistry, Polymer Chemistry, Box 538, Uppsala University, SE-751 21 Uppsala, Sweden. emma.kristensen@fysik.uu.se
Nederberg
Fredrik
F
Rensmo
Håkan
H
Bowden
Tim
T
Hilborn
Jöns
J
Siegbahn
Hans
H
D004583:Electrons; D007700:Kinetics; D015394:Molecular Structure; D010767:Phosphorylcholine / Q000737:chemistry*; D010777:Photochemistry; D011108:Polymers / Q000737:chemistry*; D011437:Propylamines / Q000737:chemistry*; D012821:Silanes / Q000737:chemistry*; D012825:Silicon / Q000737:chemistry*; D013057:Spectrum Analysis; D013499:Surface Properties
D011108:Polymers; D011437:Propylamines; D012821:Silanes; D010767:Phosphorylcholine; C088294:3-aminopropyltrimethoxysilane; D012825:Silicon