RELAXATION WITHOUT SPIN-DIFFUSION IN FRACTAL SYSTEMS - POLYMERS IN GLASSY SOLUTIONS

We describe the nuclear relaxation of protons by paramagnetic centers in glassy solutions of polymers. Both the protons and the paramagnetic radicals are on the polymers? and the solvent is fully deuterated. Tw o cases have been analyzed, ti?at when the relaxing centers are random ly distributed, and that when each polymer has a single center grafted at one end. The analysis was made for dilute and semi-dilute solution s of polymers. Experiments performed on poly-2 vinyl pyridine (P2VP) a nd on polystyrene yield results in agreement with theory, both as rega rds the NMR and the polymer models. (C) 1997 American Institute of Phy sics.