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The 4-generation carbosilane dendrimer with terminal cyanobiphenyl mesogenic groups in dilute solution of CDCl(3) was investigated using (1)H NMR technique. The spectrum was obtained and the relaxation time, T(1), was measured in the temperature range 320-225 K. For the first time, the extrema of T(1) values were achieved for majority of the dendrimer functional groups. The values of activation energies of the dendrimer functional groups were obtained. The relaxation data for outer and inner methyl groups show that the dendrimer investigated has dense corona and hollow core. This structure is formed because the mesogenic groups do not allow terminal segments to penetrate into the dendrimer, that is, the backfolding effect is absent. The NMR spectral and relaxation data give evidence for changing conformation of the dendrimer internal segments with decreasing temperature. This reorganization is most likely connected with a change of dendrimer size. We suppose that our experimental results will provide additional information for understanding principles of dendrimer nanocontainer operation. NMR can possibly be a tool for indicating the encapsulation effect as well as the dendrimer effective size.

The relationships of the time of spin-lattice relaxation and the nuclear Overhauser effect for various empirical distributions of correlation times used for the description of the relaxation properties of polymers and for two polymer chain models are considered. The dependence of the frequency-time behaviour of T1c and NOE on the shape, width, and asymptotic behaviour of the spectra of correlation times is established for short and long times. The values of T1c and NOE were found to be sensitive to the parameters of the spectra and can serve to distinguish them. Verteilung der Korrelatiomzeiten und Beziehungen zwischen der kernmagnetkchen Relaxation (1") und dem Nuklear-Overhauser-EffektDie Beziehungen zwischen der Spin-Gitter-Relaxationszeit und dem Nuklear-Overhauser-Effekt werden fur verschiedene empirische Korrelationszeitverteilungen, die fur die Beschreibung der Relaxationseigenschaften von Polymeren verwendet werden, sowie fur zwei Modelle der Polymerketten betrachtet. Daraus wird die Abhangigkeit des Frequenz-Zeit-Verhaltens von Tlc und NOE von der Form, der Breite und dem asymptotischen Verlauf der Korrelationszeitspektren fur kurze und lange Zeiten abgeleitet. Es wurde festgestellt, daD die Werte von TIC und NOE empfindlich gegenuber den Parametern der Korrelationsspektren sind und dazu dienen konnen, zwischen diesen zu unterscheiden. Pacnpeaeaenue epeaen icoppeasyuu u aa~onoaepnocmu depnoii &azxumnoii peaaacayuu (1°C) u 3g6g6e~ma OsepxayaepaPaCCMOTpeHa 3aBHCHMOCTb BpeMeHH CnEIH-PeIiIeTOYHOfi PeJIaKCaqIIll H 3@@?KTa OBepXay3epa EJIR pa3JIHYHhIX PaCnpeAeJIeHHfi BpeMeH KOppeJIR.qEIEI HCnOJIb3yeMbIX AJIR OIIHCElHHR peJIaKCaqH0HHbIX CBOaCTB IIOJIEIMepOB H EJIR ABYX MOAeJIefi IIOJIMMepHOfi qenH. YCTaHOBJTeHa 3aBHCHMOCTb YaCTOTHO-BpeMeHHOI' O IXOBe~eHHR. TIC H NOR OT @OPMbI, lUEIPHHbI H aCHMnTOTHYeCKOr0 IlOBeAeHHR CneKTpOB BpeMeH KOppeJIR~MM AJIR MaJIbIX H 6 o n b m~x BpeMeH. BeJIEIsHHbl T I C H NOE OKa3aJIHCb YYBCTBHTeJIbHbIMH K IIapaMeTpaM CneKTpOB EI M O r Y T C J I Y a U T b AJIR HX AHCKPIIMII-H a u H H .

Many characteristic features of the relaxation spectra of the different types of polymer networks (meshlike and tree‐like) manifesting in experimental behaviour are determined by manifold types of local and long‐range irregularities or inclusions existing even in the simplest network structures. These irregularities in the local topology, in the fluctuations of the local orientational order existing due to stretching of the chains in the bulk elastomers (even in the non‐ordered elastomers), also due to possible LC‐ordering, the distribution of chain lengths between junctions and possible existence of cross‐link agglomerations and domains at random cross‐linking and the influence of the position of the chain element relative to junctions lead to variety of relaxation spectra, frequency and time‐dependencies. The long‐range hydrodynamic effects in bulk network can also lead to drastic variation of relaxation spectra. The inclusion of elongated rigid particles in polymer gels and network leads to the appearance of new branches of relaxation spectra changing and overlapping the relaxation spectra of the primary network system.

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