“Bridge” Makes Differences to the Self-assembly of Block Copolymers

doi:10.6023/A20090438

Abstract

To form “bridge” via the self-assembly of block copolymer provides a useful way for the fabrication of network structures of excellent mechanical properties, which is promising in applications. However, previous work has hardly paid attention to the impact of “bridge” on the self-assembly behavior of block copolymers. This account provides a review of a recent progress about the control of the self-assembly behaviors of block copolymers via the stretching degree of the bridging block. Accordingly, we have purposely designed BABCB linear multiblock copolymer. When BABCB copolymer self-assembles into binary mesocrystal structures (sphere or cylinder), the middle B-block connects a pair of A and C domains (“macromolecular atom” aggregated by blocks) naturally forming bridge. The stretching degree of the middle bridging B-block can be increased by reducing its length relative to the other two B-blocks, lowering the coordination numbers (CNs) of mesocrystal. Moreover, the asymmetry of CNs between A and C “macromolecular atoms” can be tuned by the asymmetry between the two end B-blocks. Abiding by the two principles, using self-consistent field theory (SCFT) we have predicted rich binary mesocrystals of equal and unequal CNs. Furthermore, we have extent the concept of “stretched bridge” into AB-type block copolymers. We have proposed the effect of combinatorial entropy to realize high-ratio bridging configurations in the self-assembled structures by AB-type block copolymers. By increasing the stretching degree of bridging blocks, we have successfully predicted nonclassical square array and graphene-like array of cylinders instead of the usual hexagonal array of cylinders. In future, it is hopeful to recast most of known atomic/ionic binary crystal structures or even beyond by considering topology and blending during the design of ABC-type block copolymers.

Key words: bridge, block copolymer, self-assembly, mesocrystal, self-consistent field theory

Cite this article

Weihua Li. “Bridge” Makes Differences to the Self-assembly of Block Copolymers[J]. Acta Chimica Sinica, 2021, 79(2): 133-138.

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Fig. & Tab. 8

Figure 1. Schematics demonstrating the effect of stretching bridging block on the formation of binary mesocrystals from the self-assembly of ABC-type block copolymers. The left panel presents a typical chain configuration of ABC linear triblock copolymer in the tetragonal binary mesocrystal, where the middle bridging B-block forms a large loop. The right panel shows a typical configuration of BABCB pentablock copolymer in the three-coordinated mesocrystal, where the middle bridging B-block is highly stretched.

Figure 2. Free-energy comparison as well as the transition sequence of different mesocrystals in BABCB block copolymers with χABN=χBCN=χACN=80, fA=fC=f and fB1=fB3 (Reproduced from Ref. [15]. Copyright 2020. American Chemical Society).

Figure 3. Schematics illustrating that A-sphere (red) is larger than C-sphere (blue) in the binary mesocrystal formed by ABCB tetrablock copolymer with χ ABN=χBCN=χACN and fA=fC.

Figure 4. Phase diagram with respect to fand fB2 of AB2CB3 tetrablock copolymer with χABN=χBCN=χACN=80 and fA=fC=f, as well as the schematic plots for some typical ordered structures (Reproduced from Ref. [15]. Copyright 2020. American Chemical Society).

Figure 6. Schematics illustrating the bridging or looping configuration formed by ABA linear and (AB)n star block copolymer architectures (Reproduced from Ref. [36]. Copyright 2020. American Chemical Society).

Figure 7. Left: schematic plot of the architectures of two designed AB-type multiblock copolymers, M1 and M2. Center: illustrative plot of chain configurations in three typical cylindrical morphologies with different coordination numbers demonstrating the formation of bridges among neighboring domains and their impact on the domain arrangement (i.e., packing lattice). Right: density profiles of the stable morphologies self-assembled from the two block copolymers (Reproduced from Ref. [35]. Copyright 2020. American Physical Society).

Figure 8. “Effect of stretched bridge” and “effect of released packing frustration” are realized simultaneously in the ordered morphologies self-assembled by a purposely designed AB-type block copolymer melt, leading to the formation of a number of low-coordinated single mesocrystal structures. It is necessary to point out that B 2-block can also forming a looping configuration in addition to the bridging one, that is, A1/A2- and A3-blocks are located within the same A-domain. The looping configuration of B2-block is not shown in the schematic (Reproduced from Ref. [45]. Copyright 2020. American Chemical Society).

References 48

[1]	Bates F.S.; Fredrickson G.H. Ann. Rev. Phys. Chem. 1990, 41, 525.
[2]	Hamley I.W. Prog. Polym. Sci. 2007, 32, 1152.
[3]	Kim H.C.; Park S.M.; Hingsberg W.D. Chem. Rev. 2010, 110, 146.
[4]	Li W.H.; Müller M. Prog. Polym. Sci. 2016, 54-55, 47.
[5]	Bates F.S.; Hillmyer M.A.; Lodge T.P.; Bates C.M.; Delaney K.T.; Fredrickson G.H. Science 2012, 336, 434.
[6]	Matsen M.W. Macromolecules 2012, 45, 2161.
[7]	Liu D.; Wang Y.Y.; Sun Y.C.; Han Y.Y.; Cui J.; Jiang W. Chin. J. Polym. Sci. 2018, 36, 888.
[8]	Liu K.; Yang C.M.; Yang B.M.; Zhang L.; Huang W.C.; Ouyang X.P.; Qi F.G.; Zhao N.; Bian F.G. Chin. J. Polym. Sci. 2020, 38, 92.
[9]	Shi A.C. Development in Block Copolymer Science and Technology, Wiley, New York, 2004.
[10]	Fredrickson G.H. The Equilibrium Theory of Inhomogeneous Polymers, Oxford University Press, Oxford, 2006.
[11]	Matsen M.W.; Schick M. Phys. Rev. Lett. 1994, 72, 2660.
[12]	Drolet F.; Fredrickson G.H. Phys. Rev. Lett. 1999, 83, 4317.
[13]	Tzeremes G.; Rasmussen K.Ø.; Lookman T.; Saxena A. Phys. Rev. E 2002, 65, 041806.
[14]	Rasmussen K.Ø.; Kalosakas G J. Polym. Sci. Part B: Polym. Phys. 2002, 40, 1777.
[15]	Xie N.; Liu M.J.; Deng H.L.; Li W.H.; Qiu F.; Shi A.C. J. Am. Chem. Soc. 2014, 136, 2974.
[16]	Qiang Y.C.; Li W.H. Macromolecules 2020, 53, 9943.
[17]	Xu Y.C.; Li W.H.; Qiu F.; Yang Y.L.; Shi A.C. J. Phys. Chem. B 2010, 114, 14875.
[18]	Li W.H.; Qiu F.; Shi A.C. Macromolecules 2012, 45, 503.
[19]	Liu M.J.; Li W.H.; Qiu F.; Shi A.C. Macromolecules 2012, 45, 9522.
[20]	Xie N.; Li W.H.; Qiu F.; Shi A.C. ACS Macro Lett. 2014, 3, 906.
[21]	Xia B.K.; Li W.H.; Qiu F. Acta Chim. Sinica 2014, 72, 30. (in Chinese)
	夏彬凯, 李卫华, 邱枫, 化学学报, 2014, 72, 30.
[22]	Xia Y.M.; Li W.H. Polymer 2019, 166, 21.
[23]	Shao Z.W.; Zhang D.; Hu W.G.; Xu Y.C.; Li W.H. Polymer 2019, 177, 202.
[24]	Xie N.; Liu M.J.; Deng H.L.; Li W.H.; Qiu F.; Shi A.C. J. Am. Chem. Soc. 2014, 136, 2974.
[25]	Duan C.; Zhao M.T.; Qiang Y.C.; Chen L.; Li W.H.; Qiu F.; Shi A.C. Macromolecules 2018, 51, 7713.
[26]	Miyamori Y.; Suzuki J.; Takano A.; Matsushita Y. ACS Macro Lett. 2020, 9, 32.
[27]	Liu M.J.; Qiang Y.C.; Li W.H.; Qiu F.; Shi A.C. ACS Macro Lett. 2016, 5, 1167.
[28]	Lindsay A.P.; Lewis R.M.; Lee B.; Peterson A.J.; Lodge T.P.; Bates F.S. ACS Macro Lett. 2020, 9, 197.
[29]	Zhao B.; Jiang W.B.; Chen L.; Li W.H.; Qiu F.; Shi A.C. ACS Macro Lett. 2018, 7, 95.
[30]	Ahn S.; Kim J.K.; Zhao B.; Duan C.; Li W.H. Macromolecules 2018, 51, 4415.
[31]	Ahn S.; Seo Y.; Kim J.K.; Duan C.; Zhang L.X.; Li W.H. Macromolecules 2019, 52, 9039.
[32]	Zhao M.T.; Li W.H. Macromolecules 2019, 52, 1832.
[33]	Müller A.J.; Lindsay A.P.; Jayaraman A.; Lodge T.P.; Mhanthappa M.K.; Bates F.S. ACS Macro Lett. 2020, 9, 576.
[34]	Matsen M.W. J. Phys.: Condens. Matter 2002, 14, R21.
[35]	Gao Y.; Deng H.L.; Li W.H.; Qiu F.; Shi A.C. Phys. Rev. Lett. 2016, 116, 068304.
[36]	Li W.H.; Duan C.; Shi A.C. ACS Macro Lett. 2017, 6, 1257.
[37]	Jiang W.B.; Qiang Y.C.; Li W.H.; Qiu F.; Shi A.C. Macromolecules 2018, 51, 1529.
[38]	Xie Q.; Qiang Y.C.; Li W.H. ACS Macro Lett. 2020, 9, 278.
[39]	Matsen M.W.; Thompson R.B. J. Chem. Phys. 1999, 111, 7139.
[40]	Hermel T.J.; Hahn S.F.; Chaffin K.A.; Gerberich W.W.; Bates F.S. Macromolecules 2003, 36, 2190.
[41]	Fleury G.; Bates F.S. Macromolecules 2009, 42, 3598.
[42]	Bates F.S.; Fredrickson G.H. Phys. Today 1999, 52, 32.
[43]	Qin J.; Bates F.S.; Morse D.C. Macromolecules 2010, 43, 5128.
[44]	Spencer R.K.W.; Matsen M.W. Macromolecules 2017, 50, 1681.
[45]	Xie Q.; Qiang Y.C.; Chen L.; Xia Y.M.; Li W.H. ACS Macro Lett. 2020, 9, 980.
[46]	Schulze M.W.; Lewis R.M.; Lettow J.H.; Hickey R.J.; Gillard T.M.; Hillmyer M.A.; Bates F.S. Phys. Rev. Lett. 2017, 118, 207801.
[47]	Lindsay A.P.; Lewis R.M.; Lee B.; Peterson A.J.; Lodge T.P.; Bates F.S. ACS Macro Lett. 2020, 9, 197.
[48]	Miyamori Y.; Suzuki J.; Takano A.; Matsushita Y. ACS Macro Lett. 2020, 9, 32.

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