Τίτλος:
Architecturally-induced tricontinuous cubic morphology in compositionally symmetric miktoarm starblock copolymers
Γλώσσες Τεκμηρίου:
Αγγλικά
Περίληψη:
We report the synthesis and morphological characterization of a miktoarm block copolymer architecture: (PSαM-PIM)n-(PSM-PI αM)n, where M ∼ 20 000, n = 1, 2, and the arm asymmetry parameter α = 1, 2, or 4 (α is the ratio of the outer block molecular weight to that of the inner block). These block copolymers are symmetric in overall composition and exhibit n- and α-dependent microdomain morphologies. Alternating lamellae are observed for linear tetrablocks (n = 1), α = 1, 2, 4, and for inverse starblock (n = 2), α = 1, 2. An architecturally-induced morphological transition from lamellae to a tricontinuous cubic structure is observed with n = 2 and α = 4. The formation of the tricontinuous cubic microdomain structure in this compositionally symmetric system is thought to relieve the overcrowding of the four peripheral PS-PI junctions by providing a curved intermaterial dividing surface with a triply periodic microdomain structure, allowing some bridging by the interior blocks of the miktoarm star.
Συγγραφείς:
Tselikas, Y.
Hadjichristidis, N.
Lescanec, R.L.
Honeker, C.C.
Wohlgemuth, M.
Thomas, E.L.
Περιοδικό:
Macromolecules
Εκδότης:
American Chemical Society
Λέξεις-κλειδιά:
Anionic polymerization; Characterization; Conformations; Entropy; Molecular structure; Molecular weight; Molecules; Morphology; Synthesis (chemical); Volume fraction, Periodic microdomain structure; Tricontinuous cubic morphology, Block copolymers
