Chemistry Reference
In-Depth Information
b
a
O
O
OH
O
n
O
m
Br
O
O
d
d
e
O
O
c
b
e
a
c
c
d
e
c
HO
m
b
b
c
O
O
a
b
c
a
c
a
a
3
2
1
7
6
5
4
Chemical Shift (ppm)
Figure 4.23
1
H NMR spectra of PCL-Br, PAEDA-OH and PCL-
b
-PAEDA block
copolymers. Reproduced with permission from P P.A. Wilbon, Y. Zheng, K. Yao,
C. Tang,
Macromolecules
, 2010,
43
, 21, 8747. ©2010 American Chemical Society
[4]
4.6.2 Degradability and Thermal Properties of Diblock Copolymers of
2-Acryloyloxyethyl Dehydroabieticcarboxylate and Caprolactone
Degradability tests of diblock copolymers of AEDA and CL were carried out in acidic
solutions and characterised by GPC to observe the change of molecular weight.
The GPC traces (
Figure 4.21
) showed a clear shift to lower molecular weight with
symmetric distribution, presumably from the undegraded PAEDA block. The CL block
was completely degraded and this was confirmed by
1
H NMR. Early reports indicated
that the rosin acid moiety is potentially biodegradable by microbes [148, 149].
