Studies Of Confined Molecular By Nuclear Magnetic Resonance

This work has two parts. The first part focuses on the thickness of the interphase between the inner surface and the water phase in the mesopores of the hydration mesoporous material (MCM-41and SBA-15). By using the dipolar filter-spin diffusion NMR, the thickness of the interphase is measured directly. The results demonstrate that the thickness of the interphase decreases with increasing temperature, and at the same temperature the mesoporous material with small pore size has a thicker interphase than that having a bigger pore size. In the second part, PFG-NMR was used to monitor the chain diffusion of polystyrene sulfonic sodium in water solution. The effects of concentration, degree of sulfonation, molecular weight, molecular weight distribution, chain entanglement,and different ions on the diffusion coefficients, have been studied. It found that in the dilute solution system the local electrophoretic effect has an influence on the chain diffusion of the polystyrene sulfonic ions, leading the derease of the chain diffusion coefficient.