Formal carbons, spin-lattice relaxation times

In addition, the formal unit itself offers a new opportunity for monitoring chain motion relative to the polycarbonates since the carbonate unit contains no protons. The spin-lattice relaxation times, T s of all protons and all carbons with directly bonded protons are reported for the polyformal. Also the carbon and proton Tj s are measured at two different Larmor frequencies to expand the frequency range covered by the study. 

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