Study On The Influence Factors Of The Phase Separation Of Charged Polystyrene Colloidal Particles

The study of phase separation has important significance and application value for the explanation of natural phenomena,industry and life,while colloid particle system is often used to study the basic rule and mechanism of crystallization,melting,glass transitionand phase separation.Colloidal system is a thermodynamic stable system,which is usually a homogeneous and stable solution,and it is difficult to separate phase.Scientists have made many studies and discussions on phase separation of colloidal systems,but there is still a lack of unified understanding of the law of its change.Studying the basic conditions and mechanism of phase separation of colloidal particle system is expected to realize the control of phase separation process of colloidal system,and has a guiding and referential significance to biology,medicine,materials science and other fields.In this paper,the phase transition of the colloidal system was studied at first,then the effect of colloid concentration,ion exchange resin,salt ion and ion exchange resin position on the phase separation process of charged polystyrene colloid particle system was studied.The conclusion is as follows:?1?the concentration of phase transition node of charged polystyrene colloidal particle system was obtained,the concentration of crystallization point was 0.0586%,and the solubility of melting point was 0.0634%.When the concentration was less than 0.0586%,the colloidal particle system was in a disordered state and colloidal particles did not crystallize.When the concentration is 0.0634%<w<0.171%,the crystallization mode of the colloidal particle system is mainly heterogeneous nucleation growth.When the concentration of w>was 0.30%,the crystallization mode of the colloidal particle system was mainly homogeneous nucleation,and when the concentration was 0.171%<w<0.30%,the crystallization mode of the colloidal particle system was mainly the competitive growth of homogeneous nucleation and heterogeneous nucleation.?2?Ion exchange resin is the key factor for the separation of charged polystyrene colloidal particles.Phase separation occurs only in the presence of ion-exchange resins in the system.?3?The addition of salt ions can accelerate the phase separation,and when NaCl concentration is within a certain range,the phase separation process can be effectively promoted.For the colloidal particle system used in this study,the appropriate NaCl concentration range is 0.14639846×10^-5mol/mL-0.375×10^-3mol/mL.?4?The position of ion-exchange resin can also affect the phase separation process.For colloidal particle solutions that have been deionized without NaCl,the colloidal particle system can only undergo phase separation when the solution is located above the ionic exchange resin.If NaCl is added to the solution of colloidal particles,the colloidal particle system can only undergo phase separation when the solution is located below the ion exchange resin.?5?Combined with the experimental results,and through the analysis of the electric field force generated during the ion exchange process,it is concluded that the phase separation process can only occur when the electric field force received by the particle is in the same direction as gravity...