Studies Of Lignosulphonates Solutions Behaviour

Lignin is one kind of natural polymer with the ability to regenerate.After sulfonation,the lignin was named as sulfonate which can be dissolved that is advanced than the normal lignin. This paper is aimed to study the property of lignosulfonate solutions mainly on its surface tension, adsorption,dissolution and rheological bahavior.The structure and morphology,granularity and viscosity of lignosulphonates are studied using the FTIR spectroscopy,laser scatter measurement and Ubbelohde viscometer,respectively.Utilization of the capillary rise and the combing rules of van Oss-Chaudhury-Good to study dynamic adsorption and surface tension of the lignosulfonates respectively.The resultes showes that balance of adsorption that lignosulfonates adsorb the different kinds of liquid is established in several ten secondes,which belongs the non-pore adsorption of polymers.Based on recorded dynamic adsorbing curves,the adsorption behavior of lignosulfonates was described by a mathematical model,e.g.dW/dt=k₀+k₁W+k₂W².To analyze the k values found that the constants,ko and k₁,are quite small,this suggests that the adsorption of lignosulfonates is probably controlled by the two rate constant-based kinetics.Using the van Oss-Good-Chaudhury theories to calculated the surface tensions of lignosulfonates.Bacause the basal parameter contact angle is changes that the results of surface tension for lignosulfonates belongs dynamic dates.The behaviour for the dissolution of lignosulphonate is researched by the conductivity measurement.Results show that the dissolution temperature,concentration of lignosulphonate and sulphonation ions has significant effects on the dissolution process of lignosulphonate.The dissociation kinetics of lignosulphonate is a complex reaction process,however,to be mainly controlled by the zero reation rates constant.In this process,the effects from dissolution temperature,concentration of lignosulphonate and sulphonation ions have been discussed.The rheological behaviors of three lignosulfonates(LGSs) were studied using a rotary viscosimeter.Results showed that there has a critical shear rateγ_c which lead the theological properties of LGS solution in two regions.Thisγ_c is influenced by the molecular weight and temperature.The concentration has been found also to influence the rheological properties of LGS solution because its smaller related to both the shear-thinning and thickening and its greater related to only the shear thinning or thickening and those are availably described by the non-Newtown index.