Discrete Giant Polymer Chains Blends: Chain-Length Asymmetry, Regio-Configuration, and Multicomponent Interplay

Abstract

This work systematically investigates the bulk self-assembly behavior of binary and ternary blends of discrete giant polymer chains, focusing on the impact of chain-length asymmetry (γ), number fraction of long chains (nA), and regio-configuration. In binary blends with large chain-length disparity at low nA (0.1–0.17), a nanoscale phase coexistence with fixed domain spacings emerges, manifesting as two distinct lamellar phases with invariant periodicities. This behavior directly reflects size incompatibility rather than continuous mixing. Separately, a microconfinement-driven ordering effect is demonstrated: intrinsically disordered long chains (e.g., p-C8D) are forced into ordered lamellar structures when blended with a minor fraction of ordered short chains, a process confirmed to be thermally reversible. Regio-configuration further modulates the swollen lamellar spacing by altering chain conformation. Extending to ternary blends, a third component with intermediate chain length promotes ordered hexagonal (HEX) or body-centered cubic (BCC) phases from initially disordered binary systems, we attribute this to a “chain-length complementation” effect, where the third component relieves packing frustration caused by chain-length disparity. These findings reveal how chain-length distribution shape, regio-regularity, and multicomponent synergy regulate nanostructures, offering a rational route toward ordered nanomaterials with tunable lattice symmetries.