The experimental investigation on the conformation of a thermotropic main-chain nematic polymer by small-angle X-ray scattering (SAXS) has been carried out. The average radius of gyration of the polymer has been deter...The experimental investigation on the conformation of a thermotropic main-chain nematic polymer by small-angle X-ray scattering (SAXS) has been carried out. The average radius of gyration of the polymer has been determined in nematic and isotropic state respectively. The experiment shows that the boundary between domains is not sharp but diffuse, and the diffuse-boundary thickness of the polymer as a function of temperature has been given.展开更多
In this paper we investigate the dendritic formation of a discotic liquid crystal RHO as well as their growth characters and time evolution. The experiment shows that the dendritic structure of RHO mesophase is sensit...In this paper we investigate the dendritic formation of a discotic liquid crystal RHO as well as their growth characters and time evolution. The experiment shows that the dendritic structure of RHO mesophase is sensitive to the surface treatment, the thickness of the liquid film and the basal wall. The tip speed of the dendrite keeps constant when cooling the sampie continuously. A linear dependence of the tip speed of the dendrite on the cooling rate has been given. In order to explain the contradiction between the experiment and the present simplified theory, we suggest that the thermal fluctuation and dimension play an important role under the condition of far-away-from-the-equilibrium-state and continuous cooling.展开更多
文摘The experimental investigation on the conformation of a thermotropic main-chain nematic polymer by small-angle X-ray scattering (SAXS) has been carried out. The average radius of gyration of the polymer has been determined in nematic and isotropic state respectively. The experiment shows that the boundary between domains is not sharp but diffuse, and the diffuse-boundary thickness of the polymer as a function of temperature has been given.
基金Project supported by the National Natural Science Foundation of China.
文摘In this paper we investigate the dendritic formation of a discotic liquid crystal RHO as well as their growth characters and time evolution. The experiment shows that the dendritic structure of RHO mesophase is sensitive to the surface treatment, the thickness of the liquid film and the basal wall. The tip speed of the dendrite keeps constant when cooling the sampie continuously. A linear dependence of the tip speed of the dendrite on the cooling rate has been given. In order to explain the contradiction between the experiment and the present simplified theory, we suggest that the thermal fluctuation and dimension play an important role under the condition of far-away-from-the-equilibrium-state and continuous cooling.
