Weight average molecular weight (
Mw) of sodium carboxymethylcellulose (NaCMC) has been determined by the light scattering in the solution of triethylenediamine cadmium hydroxide (cadoxene). The relation between
Mw and the limiting viscosity number [η] in 0.1N NaCl aqueous solution has been obtained and it has been found that the Staudinger's relationship [η]=
KMw can be applied for these systems.
Dynamic viscoelastic properties of aqueous disperse systems of NaCMC have been measured by means of a cone-and-plate type rheometer. Using three series of NaCMC in the range of substitution (carboxymethyl residue/glucose unit) 0.5 to 1 with various degree of polymerization, the effects of the degree of substitution (
DS), the degree of polymerization and the concentration upon rheological properties have been investigated. The influence of
DS is marked in the long time-scale region. NaCMC of low
DS remarkably shows a second plateau which is a characteristic property of the heterogeneous system. On the other hand, NaCMC of high
DS behaves like homogeneous polymeric liquid.
抄録全体を表示