Poly CRAMPS spectrum

Fig. 6.1.3. Solid HETCOR spectrum of poly(2,6-dimethyl-/7-phenylene oxide). Note that the CRAMPS spectrum for protons in this sample, shown on the left axis, is a superposition of peaks belonging to different carbon species, as indicated by the 2D separation on the horizontal axis [29].

Figure 7.8 300 MHz CRAMPS spectrum of poly(ethylene adipate). 64 transients, relaxation delay 10 s. Reprinted with permission from [129]. (c) (1992) American Chemical Society.

Poly (I.-valine) (PL Vchain-length dependence of H chemical shifts. Figure 24 shows the H CRAMPS NMR spectra of poly(L-valines) (A) [Val]n-1 (DPn is about 5, /3-sheet form) and (B) [Val]n-5 (DPn = 100, /3-sheet) in the solid state. The shoulder peak around 1.2-1.5 ppm in spectrum A is assigned to the —N—CH2— peak of the n-butylamide (—NHBu) group. It is well known that PLV is easily stabilized in /3-sheet form whereas it is very difficult to take an... 

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