CaltechAUTHORS
  A Caltech Library Service

Design, Synthesis, and Self-Assembly of Polymers with Tailored Graft Distributions

Chang, Alice B. and Lin, Tzu-Pin and Thompson, Niklas B. and Luo, Shao-Xiong and Liberman-Martin, Allegra L. and Chen, Hsiang-Yun and Lee, Byeongdu and Grubbs, Robert H. (2017) Design, Synthesis, and Self-Assembly of Polymers with Tailored Graft Distributions. Journal of the American Chemical Society, 139 (48). pp. 17683-17693. ISSN 0002-7863. http://resolver.caltech.edu/CaltechAUTHORS:20171113-102011314

[img] PDF - Accepted Version
See Usage Policy.

4Mb
[img] PDF (Monomer synthesis and characterization information, kinetic analysis, compiled rate constants and reactivity ratios) - Supplemental Material
See Usage Policy.

47Mb

Use this Persistent URL to link to this item: http://resolver.caltech.edu/CaltechAUTHORS:20171113-102011314

Abstract

Grafting density and graft distribution impact the chain dimensions and physical properties of polymers. However, achieving precise control over these structural parameters presents long-standing synthetic challenges. In this report, we introduce a versatile strategy to synthesize polymers with tailored architectures via grafting-through ring-opening metathesis polymerization (ROMP). One-pot copolymerization of an ω-norbornenyl macromonomer and a discrete norbornenyl comonomer (diluent) provides opportunities to control the backbone sequence and therefore the side chain distribution. Toward sequence control, the homopolymerization kinetics of 23 diluents were studied, representing diverse variations in the stereochemistry, anchor groups, and substituents. These modifications tuned the homopolymerization rate constants over 2 orders of magnitude (0.36 M^(–1) s^(–1) < k_(homo) < 82 M^(–1) s^(–1)). Rate trends were identified and elucidated by complementary mechanistic and density functional theory (DFT) studies. Building on this foundation, complex architectures were achieved through copolymerizations of selected diluents with a poly(D,L-lactide) (PLA), polydimethylsiloxane (PDMS), or polystyrene (PS) macromonomer. The cross-propagation rate constants were obtained by nonlinear least-squares fitting of the instantaneous comonomer concentrations according to the Mayo–Lewis terminal model. In-depth kinetic analyses indicate a wide range of accessible macromonomer/diluent reactivity ratios (0.08 < r_1/r_2 < 20), corresponding to blocky, gradient, or random backbone sequences. We further demonstrated the versatility of this copolymerization approach by synthesizing AB graft diblock polymers with tapered, uniform, and inverse-tapered molecular “shapes.” Small-angle X-ray scattering analysis of the self-assembled structures illustrates effects of the graft distribution on the domain spacing and backbone conformation. Collectively, the insights provided herein into the ROMP mechanism, monomer design, and homo- and copolymerization rate trends offer a general strategy for the design and synthesis of graft polymers with arbitrary architectures. Controlled copolymerization therefore expands the parameter space for molecular and materials design.


Item Type:Article
Related URLs:
URLURL TypeDescription
https://doi.org/10.1021/jacs.7b10525DOIArticle
http://pubs.acs.org/doi/10.1021/jacs.7b10525PublisherArticle
http://pubs.acs.org/doi/suppl/10.1021/jacs.7b10525PublisherSupporting Information
ORCID:
AuthorORCID
Chang, Alice B.0000-0001-5036-2681
Lin, Tzu-Pin0000-0001-7041-7213
Thompson, Niklas B.0000-0003-2745-4945
Luo, Shao-Xiong0000-0001-5308-4576
Liberman-Martin, Allegra L.0000-0002-8447-905X
Chen, Hsiang-Yun0000-0002-6461-1519
Lee, Byeongdu0000-0003-2514-8805
Grubbs, Robert H.0000-0002-0057-7817
Additional Information:© 2017 American Chemical Society. Received: October 6, 2017; Published: November 8, 2017. This work was supported by the Department of Energy under Award Number DE-AR0000683 (ARPA-E Program) and by the National Science Foundation under Award Number CHE-1502616. A.B.C. thanks the U.S. Department of Defense for support through the NDSEG Fellowship. A.L.L.-M. thanks the Resnick Sustainability Institute at Caltech for fellowship support. The authors thank Prof. J. C. Peters for access to computational resources. This research used resources of the Advanced Photon Source, a U.S. Department of Energy Office of Science User Facility operated by Argonne National Laboratory under Contract DE-AC02-06CH11357. The authors declare no competing financial interest.
Group:Resnick Sustainability Institute
Funders:
Funding AgencyGrant Number
ARPA-EDE-AR0000683
NSFCHE-1502616
National Defense Science and Engineering Graduate (NDSEG) FellowshipUNSPECIFIED
Resnick Sustainability InstituteUNSPECIFIED
Department of Energy (DOE)DE-AC02-06CH11357
Record Number:CaltechAUTHORS:20171113-102011314
Persistent URL:http://resolver.caltech.edu/CaltechAUTHORS:20171113-102011314
Official Citation:Design, Synthesis, and Self-Assembly of Polymers with Tailored Graft Distributions. Alice B. Chang, Tzu-Pin Lin, Niklas B. Thompson, Shao-Xiong Luo, Allegra L. Liberman-Martin, Hsiang-Yun Chen, Byeongdu Lee, and Robert H. Grubbs. Journal of the American Chemical Society 2017 139 (48), 17683-17693. DOI: 10.1021/jacs.7b10525
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:83146
Collection:CaltechAUTHORS
Deposited By: Tony Diaz
Deposited On:14 Nov 2017 22:26
Last Modified:14 Dec 2017 19:35

Repository Staff Only: item control page