Preparation Of High Exchange Capacity Of Polyethylene Fiber And Purification Of Baicalin

In the paper, by using calcium carbonate as pore-form agent, adding differrent types ofsurfactants and blending melt spinning, the polyethylene ifber was prepared. Then，addinghydrochloric acid aimed to prepare porous polyethylene ifber.By solution method, the porous polyethylene ifber was grafted the styrene, thenchloromethylation and amination reaction were carried out. The experiment was designed to getthe ion exchange ifber that had high ion exchange capability. The self-made ion exchange ifberwas characterized by the means of IR spectrum, SEM and TG. The strong alkaline ion exchangeifber was applied in the extraction and separation of baicalin; the results were good and theprocess conditions were feasible.The ion exchange capability of the self-made strong alkaline ion exchange ifber couldachieve3.10mmol/g. The ifber had well adsorption for ethanol and water. The results ofcharacterization showed that the ifber’s characteristic peaks were remarkable; the morphologychange was obvious and the stability thermal was good. Performance testing results indicatedthat the ifber could meet the requirement of applacation.The optimum conditions of static absorption and desorption were obtained when theself-made strong alkali anion exchange ifber was applied to separate and puriyf the baicalin fromScutellaria baicalensis Georgi. The results showed that the purity of baicalin increased from38.87%to91.09%，nearly two times. This indicated that the process of extraction andpuriifcation of baicalin was feasible by using polyethylene strong alkali ion exchange ifber.Under the optimum conditions of static absorption，the absorption performance of baicalinby using self-made anion exchange ifber was studied. The absorpiton equilibrium data ofbaicalin on IEF was accorded with the Langmuir-type and Freundlich-type adsorpiton isothermequations. Furthermore, the adsorpiton enthalpy, the Gibbs free energy and the entropy were obtained. Besides，the kinetics of absorption of baicalin was described with moving boundarymodel. For the dominant procedure of ion diffusion through IEF，the apparent activation energy41.08kJ/"mol, reaction order2.190，rate speed constant8.435×10^-4 and kinetics equation areobtained.