Dense packed entrapment

Other aspects of these macromolecules that were discussed included glass transition temperature (Tg), spin-spin (T2) and spin-lattice (Ti) relaxation measurements, and molecular inclusion via dense packed entrapment of guest molecules. 

Typically, a fiber bundle has hundreds to thousands of fibers in an elliptical cross-section with a width of a few nuflimeters. Considering that a glass or carbon fiber has a diameter of 10 microns approximately, and if all the fibers are densely packed in a bundle, the gap between the fibers is only in the order of microns (i.e., 10 m). This is much smaller empty space than the empty space between the fiber bundles which is typically of the order of millimeters (i.e., 10 m). These two types of empty spaces give rise to two scales of permeabilities encountered by the resin flow, and they may result in microvoid entrapment inside the fiber bundles. 

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