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Layered silicates with three-dimensional microporosity within the layers have the potential to enable new applications in catalysis, adsorption and ion-exchange. Until now no such materials have been reported. However, here we present the synthesis and structure of AMH-3, a silicate with three-dimensionally microporous layers, obtained in high purity and crystallinity. AMH-3 is composed of silicate layers containing eight-membered rings in all three principal crystal directions, and spaced by strontium cations, sodium cations and water molecules. Because of its three-dimensional pore structure, acid and thermal stability, this layered material could find applications in polymer-silicate composites for membrane applications, for synthesis of combined microporous-mesoporous materials, and for the formation of new zeolites and microporous films. Its existence also opens new possibilities for the synthesis of other layered silicates with multidimensional microporous framework layers.

"Freezable" and "unfreezable" water in waxy corn starch were characterized by thermal analysis, and the mobility in those states was characterized by solid state (2)H and (1)H NMR. Water was found to be isotropically mobile for samples over a range of water contents (6.3-47% by total weight) at room temperature. Mobility increased with increasing water content and temperature. According to (1)H and (2)H NMR data, a large fraction of "unfreezable" (DSC) was relatively mobile comparable to a liquid state even down to -32 degrees C. Some anisotropically immobile D(2)O at low temperatures exhibited a solid state Pake pattern in (2)H NMR spectra, which was similar to that of frozen D(2)O (ice) with a 144 kHz splitting. The decreasing fraction of mobile water with decreasing temperature suggested that only some of the so-called "unfreezable" water could be progressively immobilized as temperature decreased. However, much of the water (>50% of water present) remained very high in mobility, regardless of the relatively rigid starch molecules in the glassy solid state.

A series ofcycloolefin copolymers (COCs) comprised of ethylene and norbornene units were characterized by NMR, W AXD, and DSC. The investigated compositional range was from 35.6 to 79.0 mol % ofnorbornene. Materials ofnorbornene content ofless than 50 mol % were found to contain blocks of ethylene units and also sequences of alternating ethylene/norbornene units. In these cases the stereoregularity of the chain was relatively high. Materials of norbornene content of more than 50 mol % were also found to contain alternating sequences but additionally showed components of a more random nature including blocks of norbornene units of varying lengths. The stereoregularity of the chain was relatively low in these cases. Differences in the WAXD of the materials were related to these differences in chemical architecture. All the materials showed one Tg which varied linearly with the composition of the copolymer.