Читать книгу The Rheology Handbook - Thomas Mezger - Страница 148

Rheopectic behavior means an increase in structural strength when performing a high-shear process which is followed by a more or less rapid but complete decomposition of the increased structural strength during a subsequent period of rest. This cycle of generation and re-composition, of increase and decrease in structural strength is a completely reversible process (see Figure 3.39). Rheopexy is sometimes called “anti-thixotropy” or “negative thixotropy” [3.9] which may lead to confusion. Rheopectic behavior is defined as a time-dependent behavior (like thixotropic behavior). Testing of rheopectic behavior is similar to the thixotropy test, with appropriate modifications (see Chapter 3.4.2.2).

Materials showing rheopectic behavior tend to inhomogeneous flow. Wall-slip effects and phase separation should always be taken into account. In industrial practice, rheopectic behavior is much less common than thixotropic behavior.