The Viscoelastic Property Of Carboxymethyl Cellulose Paste And Its Application In Reactive Dye Printing

As a major component of printing ink, paste has a great influence on the printingeffect. Most of the paste printing paste is Newtonian fluid. Its rheological propertiesare difficult to analysis with a single method. At present the study at home and abroadmainly focused on the static rheological properties of it. While paste is amacromolecule compound, viscoelasticity as one of its characteristic, the dynamicmethods are more precise to character its rheological properties. Storage modulus lossmodulus loss angle and change of complex viscosity are used to analyze itsviscoelastic behavior in the dynamic method. The viscoelastic behavior of a series ofsodium carboxymethyl cellulose (CMC) with different substitution degree, theinfluence of metal ions in the printing and dyeing water and chemical reagent in thepaste upon the viscoelastic behavior of CMC paste and the comparison of CMC pastewith alginate sodium paste which had high viscosity on the printing performance arediscussed.The study of steady shear rate showed that as the increased of substitution degreethe viscosity was reduced while printing viscosity index was increased, and behavedshear thinning, showed the pseudoplastic fluid features. With the increased of thesolid content of paste, the phenomenon was more significant. The dynamic scanningexperimental results revealed that, CMC paste had viscous effect and liquid-like phase.When the frequency was lower than10Hz and the degree substitution (DS) was lowerthan1.4, the viscosity effect was greater than the elastic effect. With the increased offrequency, the elastic effect and solid like phase were increased gradually. Under thecondition of shear stress or strain, the pastes had significant viscosity effect and liquidlike phase when DS was1.80.Sodium and magnesium ions had less effect on theviscoelasticity of CMC paste than calcium and iron. Under low frequency, pastes hadmore obvious elastic modulus and solid like phase when calcium and iron ions wereadded. After adding urea, resist salt S and sodium sulfate, the elastic effect of CMC pastes were more significant. The viscoelastic property of paste can be closelyassociated with printing performance, so it is important for the paste had stableviscosity in practical production. The best DS of CMC for printing was1.40whichhad the same printing effect with sodium alginate.