Journal of Physical Chemistry B, Vol.109, No.51, 24295-24303, 2005
Pore morphology of porous polymer particles probed by NMR relaxometry and NMR cryoporometry
The pore size distribution (PSD) and pore connectivity (PC) within porous polymer particles are probed by combining NMR cryoporometry and NMR relaxometry (spin-spin relaxation). With water as a probe molecule, the constant K in the so-called Gibbs-Thompson equation and the surface relaxivity (p(2)) were determined to be K = (420 +/- 50) K angstrom and p(2) = (0.44 +/- 0.01) x 10(-6) ms(-1), respectively. Also, the thickness of the interface layer was estimated to be of the order of one monolayer of water molecules. A detailed analysis of the complete set of NMR data enabled the morphology or pore structure to be probed, and is thoroughly discussed in the text.