Timehyphen;Dependent Flows of Dilute Solutions of Rodlike Macromolecules

摘要

For a suspension of rigid macromolecules with Brownian motion, expressions are obtained for the components of the stress tensor for any timehyphen;dependent shearing flow. The results are expressed up to terms of the fourth order as a series of memory integrals. The first two terms in the series enable one to calculate the explicit expressions for the kernel functions for secondhyphen;order viscoelasticity. It is established that the Oldroyd sixhyphen;constant model does not give kernel functions which are of the same form as those given by the molecular theory of rigid macromolecules. The general timehyphen;dependent elongational flow results are also given through terms of the third order.