Topological Constraints and Their Influence on the Properties of Synthetic Macromolecular Systems. 2. Micelle Formation of Triblock Copolymers

A simple theory for micelles in triblock copolymer-homopolymer mixtures is formulated. The model is a straightforward extension of Leibler et al.’s treatment of micelles in diblock-homopolymer blends. It is shown that the reduction in entropy due to loop formation of the middle block can have a dramatic effect on the critical micelle concentration. In many cases, it will essentially prevent micelle formation, in agreement with recent experimental observations on triblock copolymer solutions.