Chemistry Reference
In-Depth Information
Figure 8.6 GPC elution chromatograms of the DCPD-UPR-TO polymers with differ-
ent TO contents.
8.3.1.3 COPERMA Macromonomers
Structures of the products from the synthesis of COPERMA were monitored
by FT-IR,
1
H-NMR, and ESI-MS. The FT-IR spectra of castor oil, COPER, and
COPERMA are depicted in Figure 8.7. Several characteristic peaks were in-
dicated in the spectrum of castor oil: hydroxyl groups on the fatty acid chains
(around 3368 cm
1
), methyl and methylene groups (2925 and 2854 cm
1
),
and ester carbonyl groups (1744 cm
1
).
8
There were also some typical peaks
in the spectrum of COPER: hydroxyl groups (around 3368 cm
1
), methyl
and methylene groups (2923 and 2854 cm
1
), and ester carbonyl groups
(1734 cm
1
). Compared to that of castor oil, the peak intensity of COPER at
3368 cm
1
greatly increased, indicating more hydroxyl groups on the COPER
structure. The peak representing ester carbonyl groups shifted from 1744
to 1734 cm
1
, suggesting the occurrence of the alcoholysis reaction. In the
spectrum of COPERMA, several characteristic peaks can be seen: carboxyl
groups on the maleate half-esters (2500-3400 cm
1
), carboxyl groups on
the unreacted MA molecules (1850 and 1776 cm
1
), ester carbonyl groups
(1729 cm
1
), and C
ΒΌ
C groups on the MA structure (1633 cm
1
). The
appearance of the broad peak at 2500-3400 cm
1
and the shift of the ester
carbonyl groups from 1734 to 1729 cm
1
clearly reflect the occurrence of the
maleinization reaction.
The
1
H-NMR spectra of the COPER and COPERMA products are shown
in Figure 8.8. As indicated in the spectrum of COPER [Figure 8.8(a)], the
multipeaks at 3.4-3.8 ppm were hydroxyl functional methylene protons of
the polylol and the characteristic methine protons on the castor oil fatty acid
