molecule offered evidence for the formation of mushroom-shaped nano-aggregates
[69].
If indeed supramolecular clusters are formed spontaneously in bulk films of appropriately designed rod–coil systems, by inclusion of appropriate reactive units it
should be possible to convert these into molecular objects by crosslinking, while
maintaining the precise size and shape of the cluster. In order to test this hypothesis, rod–coil triblock copolymers, with structures similar to those described previously, but with a few modifications to enable crosslinking, were prepared. Stupp
and coworkers replaced the poly(isoprene) block with a poly(butadiene) (PB) block
(which contains both 1,2- and 1,4-linked repeat units), which is known to undergo
thermal crosslinking at high temperatures [70]. Additionally, the phenolic OH
y
x
n
O
O
O
OH
O
O
O
n = x + y
m
y
x
n
O
O
O
OH
O
O
O
n = x + y
y
x
n
O
O
O
O
O
O
O
O
O
O
H
OH
OH
O
H
O
O
O
n = x + y
A
B
D
C
n = x + y
m
y
x
n
O
O
O
O
O
O
O
CF 3
O
Fig. 15.18. Structures of a few representative rod–coil block
copolymers that have been investigated.
15 Nanostructured Polymers
504