Catalytic Synthesis and Characterization of Biodegradable ...

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Synthesis of Lactide‐Grafted Poly(TEMPO‐acrylamide) and
its Electrochemical Property and Biocompatibility
Figure 4.4 CV of the copolymer (PTAm-g-PLA2) at different scan rates in an aqueous
electrolyte solution of 0.1 M NaBF4.
The spin concentration of the copolymer was determined by magnetic measurement using
a SQUID technique. As determined from the Curie plots and the values for saturated
magnetization (Figure 4.5), the radical concentration of PTAm-g-PLA2 was 1.64×10 21 spin/g.
As calculated from the ratio of the radical amount determined by SQUID to the precursors
derived from the 1 H NMR spectra of PTAP-g-PLA, it can be found that more than 80% of the
TAP units was oxidized. Considering that almost all of the piperidine units were oxidized in
the PTAm homopolymer under the same experimental conditions, the PLA segment probably
inhibited the oxidation of the piperidine unit to a small extent.
Figure 4.5 Curie and χT (inset) vs. T plots for the radical copolymers obtained by SQUID measurements.