Triblock copolymers, mesogels and deformation behavior in poor solvents

Abstract

A fundamental distinction between the mesophases formed by ABA triblock copolymers and by AB diblock copolymers is the bridging of A domains by B blocks. The ABA mesophases form physically crosslinked networks characterized by non-uniform spatial distribution of high-functionality crosslinks. The swelling of these networks by selective solvents gives rise to novel "mesogels". Three theoretical aspects of these systems, focusing on the lamellar case, are considered: i) The SCF theory of the equilibrium fraction of bridging chains in mesophases formed by a melt of ABA triblock copolymers. ii) The swelling equilibrium and the deformation behavior of mesogels swollen by a selective solvent for the B blocks. iii) The deformation behavior of lamellar gels immersed in a poor solvent for the B blocks.