title: Block Co-PolyMOCs by Stepwise Self-Assembly.
abstract: We report a stepwise assembly strategy for the integration of metal-organic cages (MOCs) into block copolymers (BCPs). This approach creates "block co-polyMOC" (BCPMOC) materials whose microscopic structures and mechanical properties are readily tunable by adjusting the size and geometry of the MOCs and the composition of the BCPs. In the first assembly step, BCPs functionalized with a pyridyl ligand on the chain end form star-shaped polymers triggered by metal-coordination-induced MOC assembly. The type of MOC junction employed precisely determines the number of arms for the star polymer. In the second step, microphase separation of the BCP is induced, physically cross-linking the star polymers and producing the desired BCPMOC networks in the bulk or gel state. We demonstrate that large spherical M12L24 MOCs, small paddlewheel M2L4 MOCs, or a mixture of both can be incorporated into BCPMOCs to provide materials with tailored branch functionality, phase separation, microdomain spacing, and mechanical properties. Given the synthetic and functional diversity of MOCs and BCPs, our method should enable access to BCPMOCs for a wide range of applications.
authors.affiliation: Department of Chemistry, Massachusetts Institute of Technology , 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States.
authors.forename: Yufeng
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Department of Chemistry, Massachusetts Institute of Technology , 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States.
authors.forename: Mingjiang
authors.initials: M
authors.lastname: Zhong
authors.affiliation: Department of Chemistry, Massachusetts Institute of Technology , 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States.
authors.forename: Jiwon V
authors.initials: JV
authors.lastname: Park
authors.affiliation: Department of Chemistry, Massachusetts Institute of Technology , 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States.
authors.forename: Aleksandr V
authors.initials: AV
authors.lastname: Zhukhovitskiy
authors.affiliation: John A. Paulson School of Engineering and Applied Sciences, Harvard University , Cambridge, Massachusetts 02138, United States.
authors.forename: Weichao
authors.initials: W
authors.lastname: Shi
authors.affiliation: Department of Chemistry, Massachusetts Institute of Technology , 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States.
authors.forename: Jeremiah A
authors.initials: JA
authors.lastname: Johnson
mesh_terms: D000179:Acrylates / Q000737:chemistry; D055595:Mechanical Phenomena; D000073396:Metal-Organic Frameworks / Q000737:chemistry*; D019904:Polymethyl Methacrylate / Q000737:chemistry*
chemical_list: D000179:Acrylates; D000073396:Metal-Organic Frameworks; C032490:n-butyl acrylate; D019904:Polymethyl Methacrylate