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