粘弹性行为反映了介于液体和固体之间的材料在机械应力作用下的粘弹性综合反应。聚合物是橡胶和塑料工业的基本材料,对纺织、石油、汽车、造纸和制药工业也很重要,而且具有明显的粘弹性。它们的粘弹性特性决定了这些工业最终产品的机械性能,也决定了生产中间阶段加工方法的成功。聚合物的粘弹性特性详细地研究了基本粘弹性特性所依赖的许多变量的影响。这些因素包括温度、压力和时间;聚合物的化学组成、分子量和重量分布、分支和结晶度;用溶剂或增塑剂稀释;并与其他材料混合形成复合体系。在分子理论的指导下,粘弹性特性对这些变量的依赖性可以通过引入某些辅助概念来简化,如分数自由体积、单体摩擦系数和纠缠位点之间的间距,以提供对如何达到预期结果的定性理解和在许多情况下的定量预测。首先介绍了粘弹性的现象学理论,它允许不同类型的实验结果相互关联,并给出了许多有用的近似计算方法。 A wide variety of experimental methods is then described, with critical evaluation of their applicability to polymeric materials of different consistencies and in different regions of the time scale (or, for oscillating deformations, the frequency scale). A review of the present state of molecular theory follows, so that viscoelasticity can be related to the motions of flexible polymer molecules and their entanglements and network junctions. The dependence of viscoestic properties on temperature and pressure, and its descriptions using reduced variables, are discussed in detail. Several chapters are then devoted to the dependence of viscoelastic properties on chemical composition, molecular weight, presence of diluents, and other features, for several characteristic classes of polymer materials. Finally, a few examples are given to illustrate the many potential applications of these principles to practical problems in the processing and use of rubbers, plastics, and fibers, and in the control of vibration and noise. The third edition has been brought up to date to reflect the important developments, in a decade of exceptionally active research, which have led to a wider use of polymers, and a wider recognition of the importance and range of application of viscoelastic properties. Additional data have been incorporated, and the book s chapters on dilute solutions, theory of undiluted polymers, plateau and terminal zones, cross-linked polymers, and concentrated solutions have been extensively rewritten to take into account new theories and new experimental results. Technical managers and research workers in the wide range of industries in which polymers play an important role will find that the book provides basic information for practical applications, and graduate students in chemistry and engineering will find, in its illustrations with real data and real numbers, an accessible introduction to the principles of viscoelasticity.