Effect of Polydispersity on the Self-Assembly Structure of Diblock Copolymers under Various Confined States: A Monte Carlo Study

Han, Yuanyuan; Cui, Jie; Jiang, Wei

doi:10.1021/ma800702f

Cited by 41 publications

(36 citation statements)

References 49 publications

(96 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A flurry of theoretical [25][26][27][28][29][30][31][32][33][34] and a͒ Authors to whom correspondence should be addressed: Electronic addresses: hillmyer@umn.edu and bates@cems.umn.edu. experimental 11,27,[35][36][37][38][39][40][41][42][43] studies of polydispersity effects in AB block copolymers followed Bendejacq et al's report.…”

Section: Introductionmentioning

confidence: 99%

Polydispersity effects in poly(isoprene-b-styrene-b-ethylene oxide) triblock terpolymers

Meuler

Ellison

Qin

et al. 2009

The Journal of Chemical Physics

View full text Add to dashboard Cite

Four hydroxyl-terminated poly͑isoprene-b-styrene͒ diblock copolymers with comparable molecular weights and compositions ͑equivalent volume fractions of polyisoprene and polystyrene͒ but different polystyrene block polydispersity indices ͑M w / M n = 1.06, 1.16, 1.31, 1.44͒ were synthesized by anionic polymerization using either sec-butyllithium or the functional organolithium 3-triisopropylsilyloxy-1-propyllithium. Poly͑ethylene oxide͒ ͑PEO͒ blocks were grown from the end of each of these parent diblocks to yield four series of poly͑isoprene-b-styrene-b-ethylene oxide͒ ͑ISO͒ triblock terpolymers that were used to interrogate the effects of varying the polydispersity of the middle bridged polystyrene block. In addition to the neat triblock samples, 13 multicomponent blends were prepared at four different compositions from the ISO materials containing a polystyrene segment with M w / M n = 1.06; these blends were used to probe the effects of increasing the polydispersity of the terminal PEO block. The melt-phase behavior of all samples was characterized using small-angle X-ray scattering and dynamic mechanical spectroscopy. Numerous polydispersity-driven morphological transitions are reported, including transitions from lamellae to core-shell gyroid, from core-shell gyroid to hexagonally packed cylinders, and from network morphologies ͓either O 70 ͑the orthorhombic Fddd network͒ or core-shell gyroid͔ to lamellae. Domain periodicities and order-disorder transition temperatures also vary with block polydispersities. Self-consistent field theory calculations were performed to supplement the experimental investigations and help elucidate the molecular factors underlying the polydispersity effects. The consequences of varying the polydispersity of the terminal PEO block are comparable to the polydispersity effects previously reported in AB diblock copolymers. Namely, domain periodicities increase with increasing polydispersity and domain interfaces tend to curve toward polydisperse blocks. The changes in phase behavior that are associated with variations in the polydispersity of the middle bridged polystyrene block, however, are not analogous to those reported in AB diblock copolymers, as increases in this middle block polydispersity are not always accompanied by ͑i͒ increased domain periodicities and ͑ii͒ a tendency for domain interfaces to curve toward the polydisperse domain. These results highlight the utility of polydispersity as a tool to tune the phase behavior of ABC block terpolymers.

show abstract

Section: Introductionmentioning

confidence: 99%

Polydispersity effects in poly(isoprene-b-styrene-b-ethylene oxide) triblock terpolymers

Meuler

Ellison

Qin

et al. 2009

The Journal of Chemical Physics

View full text Add to dashboard Cite

show abstract

“…Some computational studies on self-assembly of block copolymer blends in solution have been reported in the last decade, including self-consistent-field theory (SCFT), 11,15,17,18 Monte Carlo, [19][20][21][22][23] Brownian Dynamics 24 and Dissipative Particle Dynamics. 16,[25][26][27][28][29][30][31][32][33] A number of publications focuses on block copolymer/homopolymer blends (AB/A and AB/C), 20,31,34 block copolymers in small amounts as compatibilizers for homopolymer blends (AB/A/B, AB/A/C or AB/C/D).…”

Section: Introductionmentioning

confidence: 99%

“…As far as blends of two block copolymers are concerned, few reports are available. Focus has been on AB/AB copolymers with different molecular weights 22,38 but less on AB/AC blends. AB/AC blends have been considered before, but only with similar molecular weights.…”

Section: Introductionmentioning

confidence: 99%

Topology and Shape Control for Assemblies of Block Copolymer Blends in Solution

et al. 2015

View full text Add to dashboard Cite

We study binary blends of asymmetric diblock copolymers (AB/AC) in selective solvents with a meso-scale model. We investigate the morphological transitions induced by the concentration of the AC block copolymer and the difference in molecular weight between the AB and AC copolymers, when segments B and C exhibit hydrogen-bonding interactions. To the best of our knowledge, this is the first work modeling mixtures of block copolymers with large differences in molecular weight. The co-assembly mechanism localizes the AC molecules at the interface of A and B domains, and induces the swelling of the B-rich domains. The coil size of the large molecular weight block copolymer, depends only on the concentration of the short block copolymer (AC or AB), regardless of the B-C interactions. However, the B-C interactions control the morphological transitions that occur in these blends.

show abstract

“…For the self-assembly of linear or star triblock copolymers in the confined pores, a series of morphological phase diagrams have been established using self-consistent field theory and simulated annealing method [16,[21][22][23]. Moreover, complex self-assembled structures can be generated by diblock copolymer mixtures under various confined conditions [24,25]. For example, morphological transitions from concentric cylindrical barrel structures to screw/cylinder structures and then to stacked disk/cylinder structures upon decreasing the pore diameter have been observed in the binary blends of A 15 B 7 and B 7 C 15 copolymers under cylindrical confinements.…”

Section: Introductionmentioning

confidence: 99%