A coalescence mechanism for the coarsening behavior of polymer blends during a quiescent annealing process is proposed. It suggests that the distribution state of dispersed particles in a matrix obeys a nearest-neighbor distribution function in multibody systems. Both drainage and merge stages are included in the coalescence. All existing forces, such as thermal agitation, van der Waals attraction, interfacial tension, and viscous resistance, take control of the coarsening process. A dynamic equation is used to compute the evolution of dispersed particles. An experimental investigation has been made with the time-resolved light scattering measurement of a polystyrene/ poly(methyl methacrylate) blend during an annealing process. The model predictions are in good agreement with our experiment and other authors' work. The relative effects of system parameters such as volume fraction, interfacial tension, and viscosity are also discussed.

讨论了高聚物复杂流体的内部结构张量、热力学状态空间、自由能函数和非平衡热力学唯象定律，综述了唯 象定律在处于流场力作用下的高聚物熔体的大分子构象结构、两相共混物的相结构、纤维填充高聚物复合体系的 纤维取向结构的流变方程的应用，指出了一条建立流场中高聚物复杂结构流变方程的途径。

A new constitutive model with internal structure parameter is presented in this study for simulating orientation and deformation of polymer chain in the post/filing stages of injection molding process. Implementation of such a model is based on a hybrid finite-element/finite-difference numerical solution of the generalized Hele-Shaw flow. The simulation of a compressible viscoelastic fluid under nonisothermal conditions has not yet been discussed in most previous works. In addition to the distribution of pressure, temperature, density, and velocity, theoretical predictions also include shear and normal stresses, which can be used for subsequent calcula-tion of residual stresses. An amorphous material, namely a commercial-grade poly-styrene (PS), was used in the present work. Good agreement is obtained between the simulation and experimental pressure trace from this study.

Conceptually, an imagined conformation ellipsoid is supposed to represent the shape of a polymer chain for polymer melts in flow fields and to be equivalent to the volume element in mathematical sense in continuum mechanics. A power law dependence of shear modulus of polymer melts on detC, referred to as envelope volume, is proposed. Based on those assumptions and the non-linear relation of shear modulus, a phenomenological viscoelastic model is derived. The model is tested in simple shear flow, simple elongational flow, oscillatory shear flow, and relaxation process after flow suddenly stopped. The results show that the model works well to predict the change of internal structure and viscoelastic performance of polymer melts in flow fields.

Polymer chain coils with entanglement is a crucial scale of structures in polymer materials since their relaxation times are matching practical processing times. Based on the phenomenological model of polymer chain coils and a new finite element approach, we have worked out a computer software including solver, pre and post processing modules, and developed a digital analysis technology for the morphology of polymer chain coils in flow fields (DAMPC). Using this technology we may simulate the morphology development of chain coils in various flow fields, such as simple shear flow, elongational flow, and any complex flow at transient or steady state. The applications done up to now show that the software predictions are comparable with experimental results.