流场中聚合物共混体系液滴形变的理论模型

讨论了两相聚合物共混体系中，悬浮于另一种牛顿（或粘弹）液体中的牛顿（或粘弹）液滴的形变理论模型．影响液滴形变的主要因素有两相的组成、粘度比和弹性比、动态界面张力、临界界面张力系数，外流场形式及其强度．对于两相均为牛顿流体的体系，理论预测能够与实验相符；对于两相（或其中一相）为粘弹流体的体系，由于弹性的影响而使液滴形变的研究变得复杂，理论模型尚需完善．建立完整的液滴形变理论模型还需深入研究界面层、微观分子形变、液滴之间及液滴和连续相介质之间的相互作用对液滴形变的影响

THEORETICAL MODELS OF DROPLET DEFORMATION FOR POLYMER BLEND SYSTEMS IN FLOW FIELDS

For two-phase polymer blending systems, the development of theoretical models on the deformation of Newtonian(or viscoelastical)droplet suspended in another Newtonian(viscoelastical)medium is discussed. The dominating factors which influence the droplet deformation include composition, viscosity and elasticity ratios, dynamic interfacial tension, critical capillary number, and flow field type and its intensity. For the systems in which both of the two phases are Newtonian liquids, the theoretical predictions are consistent with the experiments, whereas for the systems in which the two phases(or one of the two phases)are viscoelastical liquids, the deformation studies become very complicated due to the influence of elasticity, and the theoretical model should be improved. In order to establish a more pertinent theoretical model of droplet deformation, it is essential to study the interface layer, microscopic molecular deformation, interaction between droplets and between droplet and continuous phase media and its effect on droplet deformation.