Effect of pressure on the molecular motion of a poly(γ-benzyl l-glutamate) lyotropic liquid crystal as studied by 1H nuclear magnetic resonance

Modified data handling for rapid low‐field nuclear magnetic resonance characterization of lyotropic liquid crystal composites

“…A considerable amount of work has been reported on applying nuclear magnetic resonance (NMR) principles to understand the structure and relaxation behavior of pure LLC phases (also referred to as mesophases) formed by surfactant-water mixtures (1)(2)(3)(4)(5)(6). Low-field (or wideline) NMR techniques have been developed for quick estimation of solid-liquid ratios (7)(8)(9)(10) and for quantitative observation of protons in different chemical environments (11).…”

“…Typical spin-spin relaxation time constants (T 2 ) for most common phases encountered in surfactant systems include the following (2,6,11), where each hydrocarbon chain phase is paired with the T 2 range (in µs): solid crystal, 12-15; gel (bilayer), 20-30; L α (lamellar), 50-250; H 1 (hexagonal), 170-300; cubic, 1000; and water, ~10 5 . Thus, the time constant is in the range 12-15 µs for solids, a few hundred milliseconds for L 1 , and some intermediate value for liquid crystal (LC) phases.…”