Deuteron NMR offers the possibility of studying local motions of polypentadiene chains included into a crystalline perhydrotriphenylene matrix. Results show the copresence of a rigid and a mobile fraction of C-D bonds, mobility ranging over a wide temperature interval, from 150 K up to 360 K (close to the melting point of the host compound). The relatively scarce effect of temperature is in agreement with a model where the chain mobility is primarily governed by steric interactions with a rigid host structure. A TI relaxation analysis indicates that a simple two-fraction model is an oversimplification, a better description requiring a more complex distribution of correlation times. A complete characterization of the samples assures for the absence of unreacted monomers and for the structure of the inclusion compound.
Chain Mobility of Isotactic 1,4-trans-Poly(penta-1,3-diene)Included into Perhydrotriphenylene. A Broad-Line 2H NMR Study
1989
Abstract
Deuteron NMR offers the possibility of studying local motions of polypentadiene chains included into a crystalline perhydrotriphenylene matrix. Results show the copresence of a rigid and a mobile fraction of C-D bonds, mobility ranging over a wide temperature interval, from 150 K up to 360 K (close to the melting point of the host compound). The relatively scarce effect of temperature is in agreement with a model where the chain mobility is primarily governed by steric interactions with a rigid host structure. A TI relaxation analysis indicates that a simple two-fraction model is an oversimplification, a better description requiring a more complex distribution of correlation times. A complete characterization of the samples assures for the absence of unreacted monomers and for the structure of the inclusion compound.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
