Parallel versus Perpendicular Lamellar-within-Lamellar Self-Assembly of A-b-(B-b-A)_n-b-C Ternary Multiblock Copolymer Melts

Abstract

Take-down policy If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim.Downloaded from the University of Groningen/UMCG research database (Pure): http://www.rug.nl/research/portal. For technical reasons the number of authors shown on this cover page is limited to 10 maximum. A-b-(B-b-A) n -b Different types of lamellar-within-lamellar structure formations in A-b-(B-b-A) n -b-C terpolymer melts, with a volume fraction of components A, B, and C in the ratio of 1:1:2, are analyzed in the strong segregation limit using a simple theoretical approach. We consider the lamellar, parallel lamellar-within-lamellar, and perpendicular lamellar-within-lamellar self-assembled states. The influence of the copolymer chain length N, the value of the Flory-Huggins interaction parameters AB , AC , and BC , and the number of blocks n in the AB multiblock chain on the phase behavior is discussed. We show that in the limiting case of n . 1, the perpendicular lamellar-within-lamellar state becomes stable when the interaction parameters satisfy the relation 0 < BC < 0.22 Download date: 11-05-2018 Parallel versus Perpendicular Lamellar-within-Lamellar Self-Assembly of

Monte Carlo Simulations of the Phase Separation of a Copolymer Blend in a Thin Film

“…As shown in our recent study, [20] when the mixture of block copolymers and alternating copolymers is confined in a film, the phase separation may induce a complex lamellar structure with different repeat periods. This lamellar-in-lamellar structure is very similar to those found in multiblock copolymer self-assembly, [21][22][23][24][25][26][27][28][29] while the alternating and block copolymers in our copolymer blend system are much easier to be synthesized than that of asymmetric multiblock copolymers. [30][31][32] In this contribution, to explore the influence of system parameters such as segment distribution and segregation strength on phase separation, we design a series of polymer Monte Carlo simulations were carried out to study the phase separation of a copolymer blend comprising an alternating copolymer and/or block copolymer in a thin film, and a phase diagram was constructed with a series of composed recipes.…”

Perpendicular lamellar-in-lamellar and other planar morphologies in A-b-(B-b-A)2-b-C and (B-b-A)2-b-C ternary multiblock copolymer melts

“…This phenomenon became an attractive area of research both experimentally [1][2][3][4][5][6][7][8][9][10][11][12] and theoretically, [13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29] during the last decades. First, the two-length-scale structures, which might be called lamellar-in-lamellar structures (see Fig.…”

“…Several other examples of hierarchical structures can be found in Refs. 9-13. The morphologies occurring in multiblock copolymers with various architectures and interaction parameters were studied theoretically both within the weak [14][15][16][17] and strong segregation approach (SSA) [18][19][20][21] as well as within the framework of the self-consistent field theory (SCFT). [22][23][24][25][26][27][28][29] In particular, the transitions between the parallel lamellar-in-lamellar structures L || (n) with different numbers n of thin layers per large period were studied via the SSA [18][19][20] and SCFT.…”

“…[22][23][24][25][26][27][28][29] In particular, the transitions between the parallel lamellar-in-lamellar structures L || (n) with different numbers n of thin layers per large period were studied via the SSA [18][19][20] and SCFT. 23,[25][26][27]29 The transition between the perpendicular lamellar-in-lamellar structure (L ⊥ ) and the parallel ones L || (n) was studied via the SSA, 21 the L ⊥ phase being found to become stable for C-E-C-E-C-P-like systems when the interaction parameters satisfy the condition 0 < χ EP < 0.22χ CP ). Lines dividing 2D sections of the interaction parameter space (χ AB , χ AC , χ BC ) corresponding to the L ⊥ and L || (n) stability were obtained via SCFT.…”

Microphase separation in random multiblock copolymers

“…19 In theory, a loop is considered as two linear chains and equal probabilities of bridge and loop conformations are usually assumed. [22][23][24][25]31 The more detailed self-consistent field calculations predict the bridge fraction 0.4 for stretched monodisperse middle blocks. 34,35 Note that the combinatorial distributions of bridges and loops in the layers are impotrant for the final structure of multiblock copolymers with not large numbers of blocks in macromolecules, as shown for the copolymers with monodisperse blocks forming usual lamellar structure 31 and for the copolymers with long end blocks and many more short middle blocks forming lamellar-in-lamellar structures.…”