【作者】 李慧； 刘鸿； 吕中元； 孙家钟；

【Author】 Hui Li,Hong Liu,Zhongyuan Lu,Chia-Chung Sun (State Key Laboratory of Theoretical and Computational Chemistry,Institute of Theoretical Chemistry,Jilin University, Changchun 130023,)

【机构】 吉林大学理论化学研究所理论化学计算国家重点实验室；

【摘要】 相分离能够影响材料在应用中的诸多问题,流体中的简单化学反应同样在形态学和动力学行为上影响材料的性质。我们的模型基于耗散粒子动力学(DPD)的改进方法—Lowe-Andersen控温方法来研究伴有简单可逆反应A(?)B的二元混合物体系。结果显示由于化学反应的加入使反应与相分离之间存在竞争关系,当二者达到平衡时组分不能分相成两个连续的大相区,而是形成较小的液滴状相区,因此通过计算相区尺寸(R)的大小来描述相分离准确性较差。我们提出通过计算每对粒子间的平均相互作用能(E)来描述相分离情况,发现运用该方法能够更准确地描述相区较小的相结构,并得到与前人相同的0.5的标度关系[1,2,3,4]。另外还对反应几率pr、组分间排斥相互作用αAB以及组分粘度等因素对相分离情况的影响进行了研究。更多还原

【Abstract】 Many practical problems such as morphology control in materials science are related to the phase separation.The chemical reaction in the fluids may seriously affect the morphology patterns and the dynamic behavior of fluids.The phase-separating system coupled with a simple reversible reaction A（?）Bin a binary immiscible mixture is investigated with Lowe-Andersen temperature controlling method,which is a promising variation for dissipation particle dynamics. We present results for critical quenches.There are some smaller droplets in the original phase, rather than large continuous phase,which are induced by the competition between the reversible reaction and the phase separation.We find that,calculating the mean potential energy of each pair of particles to describe the phase separation is better than calculating the domain size.In addition, reaction probability pr determines the suppressing effect of the reversible reaction on the phase separation.The repulsion between the two componentsα_AB and the relevant parameter of viscosity also strongly influence the phase morphology in steady-state.更多还原