Biomedical Engineering Reference
In-Depth Information
Fig. 15
SEM micrographs of the nanotubes of
hb
-P
71
(6) prepared inside an AAO template
withaporesizeof
∼
250 nm
prepared from the amine-catalyzed polycyclotrimerizations by simply heat-
ing the monomer mixtures, we carried out the polymerization of
71
(6) in the
presence of an AAO template. The great advantage of this system is that it
does not suffer from any metal residues left behind after the polymerization
and the amine catalyst as well as the solvent can be easily removed. Breakage
or dissolution of the AAO templates in aqueous sodium hydroxide solution
freed the micro structures. SEM micrographs of the templated
hb
-P
71
(6) are
showninFig.15.Ascanbeseenfromthephotos,the
hb
-PAA adopted well
the shape of the template pores and formed micrometer-long polymer nano-
tubes. The hollows of the nanotubes were clearly confirmed by the magnified
images given in Fig. 15D.
3.3
Photonic, Magnetic and Catalytic Properties
Acetylenic molecules are versatile ligands in organometallic chemistry [152-
154]. Examples of acetylene-metal reactions include facile complexations
of one triple bond with Co
2
(CO)
8
[155-157] and two triple bonds with
CpCo(CO)
2
(Scheme 31) [158, 159]. The
hb
-PYs contain numerous triple
bonds and should be readily metallized through their complexations with the
cobalt carbonyls. Upon admixing
hb
-P
20
and the cobalt carbonyls in THF at
room temperature, the solution color changed from yellow to brown, accom-
panied by CO gas evolution. The mixtures remained homogenous towards
