31. Experimental study of dynamics of topological defects in nematic polymer liquid crystals
作者：Wei Wang, Toshio Shiwaku, Takeji Hashimoto
關鍵字：topological defects
論文來源：期刊
具體來源：Journal of Chemical Physics
發表時間：1998年
The dynamics of stringlike defects and the shrinkage and annihilation processes of individual defect loops in a nematic polymer liquid crystal have been experimentally investigated. In 40<t<500?s, the line density of defects ρ scales as ρ(t) ∼ t−1, as expected by theory and as found in the experimental studies of some low molecular weight (LMW) liquid crystals. For individual loops, they first change their complex shape into a circle, resulting in a rapid decrease in length, and then the circular loops continuously shrink. Before a complete annihilation, the relation between the radius R(t) of the circular loop and time t0−t, where t0 is the time to annihilation, is described by R2(t) = 2Γ(t0−t)(t ? t0). The kinetic constant Γ determined from this polymer liquid crystal is 0.34 ∼ 0.38?μm2/s, much smaller than those (200 ∼ 300?μm2/s) obtained in some LMW liquid crystals. The small Γ is ascribed to the high viscosity of this polymer liquid crystal, compared with LMW liquid crystals.