Study Of Properties Of Cationic Cellulose Ether Aqueous Solution

With the development of science and technology, more and more new materials are prepared and the studies of their chemical and physical properties appear more important for their practical application. In this study, natural-modified macromolecule cationic cellulose ether of three types was investigated. We paid main attention to their representative physical characters and expatiated some corresponding mechanism simply. Cellulose was linear macromolecular compound which was composed of 1, 4-βindican bond arraying directionally,and it was a recycle natural polymer material. It existed in most green plants which was an inconsumable resource. Furthermore, it had many excellent capabilities and was paid more and more attention on nowadays. We could get a new type functional macromolecule through modification, which had been widely applied in biocompatible sanitation products, petrochemical, pharmacies, food, personal care commodity, packing and other field. Hydrophilic cationic cellulose ether (CCE)was one of these modified cellulose, especially the quaternary ammonium salt type.Through determination of molecular weight (Mw), the second virial coefficient (A2), mean-square radius of gyration (Rg), hydrodynamic radius (Rh) of various angles in dilute solution at different pH value by ALV-5000E laser light scattering, it was deduced from Rg / Rh value that CCE had a erose morphology but close to sphere. In the meantime, the rheological properties of CCE concentrated solution were studied in detail by means of a Brookfield RVDV-III+ rheometer and the effects of concentration(ρ), charge density and pH value on their rheological properties were also studied. WhenρCCE between 0.5-25g/L, it appeared pseudoplastic behavior, but definitely thixotropic and rheopexy behavior with further increasingρCCE. Especially, it was found that viscosity behavior index (n) did not always decrease as concentration increased but fluctuated and even raised, which was different from ordinary anionic and cationic polymers. High viscosity could be achieved by moderate charge density of the polymer and pH had little effect on their viscosity.The rheological properties of cationic cellulose ether (JR-30M) were studied and the effects of concentration (ρ), temperature, pH value and additive salt on viscosity of its aqueous solution were discussed in this paper. In certain range ofρ, JR-30M appeared pseudoplastic behavior. However, viscosity behavior index (n) did not always decrease withρincreasing, in opposition to some references, it fluctuated and even raised afterρlarger than 7g/L. Its zero-shear viscosity dropped with temperature rising. In buffer solutions of pH=3-6, activation energy of viscous fluid flow (Ea) were 75.08, 48.22, 44.23 and 36.83 kJ/mol, respectively, but viscosity of these JR-30M solutions increased when pH values decreased from 3 to 6. It was deduced that JR-30M could form ordered structure or some ordered micro-region in certain acidity solution. As it was referred to adding salt of different style, the results of viscosity were complicated.Through determination of Transmission, conductivity and apparent viscosity, the interaction between KG-30M and anionic surfactants sodium dodecylsulfate (SDS) was investigated. It showed when the amount of surfactant was low, static interaction took the main status; with the amount of SDS increasing, solution changed from transparent to turbid,then wadding state deposit occurred. Gonging on adding SDS, solution showed transparent again. And the conductivity of the compound solution always rose accompanied by the phenomenon above. As for the apparent viscosity of SDS-KG compound solution rose at first, then dropped during increasing the amount of SDS, later a little fluctuation appeared.