Chains Grafted onto a Filler Surface

The molecular mobility of high-molecular-mass PDMS chains grafted to the silica surface at one end has been studied with the aid of various solid-state NMR techniques [130-132], The use of 2H NMR methods for this purpose is reviewed in the present book [133]. 

A PDMS layer chemically attached at both chain ends to the surface of hydrophilic silica has been studied by means of H T2 relaxation experiments [112]. The average length of the grafted chains in samples studied was varied from about 4 to 8 Si-O bonds. These experiments showed that the T2 relaxation method is very sensitive to the heterogeneous 

About four dimethylsiloxane pendent chain units next to the grafting site were immobilised due to chain anchoring to the silica surface. 

Reproduced with permission from V.M. Litvinov, H. Barthel and J. Weis, Macromolecules, 2002, 35. Copyright 2002, American Chemical Society 

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