Molecular Dynamics of Polycarbonate Chains at the Interface of Polycarbonate/Polystyrene Heterogeneous Blends
WASHINGTON UNIV ST LOUIS MO DEPT OF CHEMISTRY
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Having generated and identified a carbon thirteen NMR signal arising exclusively from PC chains the PCPS interface, we can now perform NMR relaxation experiments to characterize the microscopic dynamics of these chains. A difference pulse sequence is used which includes a period for carbon dephasing under the influence of dipolar coupling to protons isolated from one another by multiple-pulse H-H decoupling. Thus, the full experiment involves monitoring the dephasing of DNP-enhanced 13C NMR magnetization of interface PC chains in a thin-film PCPS blend by dipolar rotational spin echo DRSE 13 C NMR. The results of DRSE experiments have been well established for the characterization of the molecular chain dynamics of synthetic polymers and proteins.