Skip to Main Content
 

Global Search Box

 
 
 
 

Files

File List

Full text release has been delayed at the author's request until December 31, 2025

ETD Abstract Container

Abstract Header

Design, Synthesis, and Self-Assembly of Nano-Sized Shape Amphiphiles Based on Polyhedral Oligomeric Silsesquioxane and Perylene Bisimides

Huang, Jiahao
http://rave.ohiolink.edu/etdc/view?acc_num=akron1603670714151325

Abstract Details

2020, Doctor of Philosophy, University of Akron, Polymer Science.
In modern materials science and associated technology, self-assembly of molecules have been extensively utilized to fabricated desired or designed microscopic structures, which is usually referred as “bottom-up” approach. The underlying principle is that the macroscopic properties and functions of materials do not solely depend on the chemical structures and composition of constituting molecules, but also their molecular packing across multiple length scales. Compared to the tremendous efforts on the precise controls of primary chemical structures and compositions of molecules and their further correlation to the hierarchal ordered structures and macroscopic functions of materials, the explicit shape, symmetry, and size effects (geometrical effects) of molecules on their self-assembled supramolecular structures and materials properties are far from being fully appreciated and investigated. “Shape amphiphiles”, constructed by conjugating molecular building blocks with distinct shapes and competing interactions, emerge as a very promising molecular system. In this dissertation, based on conjugates of cubic functionalized polyhedral oligomeric silsesquioxanes (POSS) and discotic perylene bisimides (PBIs) and other related arylene bisimides (RBIs), the molecular design and synthesis of a class of giant shape amphiphiles with precisely defined chemical structures are presented. The dedicate balance between entropic and enthalpic interactions is critical for the supramolecular assembly of shape amphiphiles, which is highly sensitive to the subtle change of molecular size and shape of constructing molecular building blocks. Specifically, the conjugation and spatial arrangement of these two different shaped molecular building blocks were adopted in two different symmetries, facilitating the detailed investigation on the specific size, shape, and symmetry effects on their self-assembled supramolecular structures. First, a series of POSS-based giant shape amphiphiles were synthesized and investigated, which are constructed by symmetrically attaching six isobutyl-functionalized POSS (BPOSS) or octyl-functionalized POSS (OPOSS) cages to the planar aromatic cores of RBIs at their both imide positions with tunable linkage lengths and chemical structures. Consequently, by systematically tuning the size and shape of molecular building blocks and the linkage, a series of spherical packing phases were observed in these giant shape amphiphiles including body-centered cubic (BCC), Frank-Kasper (FK) A15, FK σ phase, and a rarely observed FK Z phase in soft matter. Second, adopted in a totally different tetrahedral symmetry, two giant shape amphiphiles constructed by attaching four bulky BPOSS cages to a rigid PBI-based tetrahedral scaffold were synthesized and investigated. Surprisingly, different from the spherical packing phases observed in first class of POSS-based giant shape amphiphiles, hexagonal columnar supramolecular structures were clearly identified in the second class of POSS-based giant shape amphiphiles. Therefore, it is concluded that our POSS-based giant shape amphiphiles provide a feasible platform to further explore how molecular parameters beyond primary chemical structures and compositions affect their self-assembled supramolecular structures, especially in the aspect of fine tuning on their molecular size, shape, and symmetry.
Stephen Cheng (Advisor)
Tianbo Liu (Committee Chair)
Toshikazu Miyoshi (Committee Member)
Yu Zhu (Committee Member)
Chrys Wesdemiotis (Committee Member)
248 p.
Chemistry; Materials Science; Polymer Chemistry; Polymers

Recommended Citations

Citations

  • Huang, J. (2020). Design, Synthesis, and Self-Assembly of Nano-Sized Shape Amphiphiles Based on Polyhedral Oligomeric Silsesquioxane and Perylene Bisimides [Doctoral dissertation, University of Akron]. OhioLINK Electronic Theses and Dissertations Center. http://rave.ohiolink.edu/etdc/view?acc_num=akron1603670714151325

    APA Style (7th edition)

  • Huang, Jiahao. Design, Synthesis, and Self-Assembly of Nano-Sized Shape Amphiphiles Based on Polyhedral Oligomeric Silsesquioxane and Perylene Bisimides. 2020. University of Akron, Doctoral dissertation. OhioLINK Electronic Theses and Dissertations Center, http://rave.ohiolink.edu/etdc/view?acc_num=akron1603670714151325.

    MLA Style (8th edition)

  • Huang, Jiahao. "Design, Synthesis, and Self-Assembly of Nano-Sized Shape Amphiphiles Based on Polyhedral Oligomeric Silsesquioxane and Perylene Bisimides." Doctoral dissertation, University of Akron, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=akron1603670714151325

    Chicago Manual of Style (17th edition)

akron1603670714151325
© 2020, all rights reserved.
This open access ETD is published by University of Akron and OhioLINK.