P. Monzie

Bio: P. Monzie is an academic researcher. The author has contributed to research in topics: Anhydrous & N-Methylmorpholine N-oxide. The author has an hindex of 1, co-authored 1 publications receiving 154 citations.

Oriented cellulose films and fibers from a mesophase system

Abstract: Cellulose mesophases were obtained by preparing concentrated solutions of cellulose (20–55%) in a mixture of N-methyl-morpholine N-oxide (MMNO) and water. The anisotropy depends on four interconnected parameters: the temperature of the solution which, in general, must be lower than 90°C; the concentration of cellulose which must exceed 20%; a water content such that the mole ratio water/anhydrous MMNO is smaller than unity; and the degree of polymerization of the dissolved cellulose. The anisotropic cellulose solutions can readily be oriented during extrusion or casting thus giving fibers or films which upon regeneration exhibit high orientation.

Molecular theory of liquid crystals

Abstract: The lattice theory of liquids consisting of rodlike molecules is presented and discussed with emphasis on polymers exhibiting nematic or cholesteric liquid crystallinity. Steric repulsions between the solute particles are principally responsible for order in lyotropic liquid-crystalline systems. In the case of rigid rods, the axial ratio of the particles governs the concentration at which separation of a nematic or cholesteric phase sets in. For semi-rigid chains such as those of cellulose and its derivatives, the axial ratio of the Kuhn segment is the relevant parameter. These and other predictions of the lattice theory are confirmed by numerous experiments. Liquid crystallinity may be promoted by orientation-dependent intermolecular attractions between extended chain molecules. Such forces originate in the anisotropy of the polarizabilities of groups, e.g., phenylene, in the main chain. They may be especially important in thermotropic melts and concentrated solutions.