We report a post-polymerization modification strategy to functionalize methacrylic copolymers through enol-ester transesterification. A new monomer, vinyl methacryloxy acetate (VMAc), containing both enol-ester and methacryloyl functionality, was successfully copolymerized with methyl methacrylate (MMA) by selective reversible addition–fragmentation chain transfer (RAFT) polymerization. Post-polymerization modification of pendent enol esters proceeded through an “irreversible” transesterification process, driven by the low nucleophilicity of the tautomerization product, to result in high conversion under mild conditions.
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Post-Polymerization Modification of Ring Opening Metathesis Polymerization (ROMP)-Derived Materials Using Wittig Reactions
This communication describes our recent efforts to utilize Wittig olefination reactions for the post-polymerization modification of polynorbornene derivatives prepared through ring opening metathesis polymerization (ROMP). Polymerizing α-bromo ester-containing norbornenes provides polymers that can undergo facile substitution with triphenylphosphine. The resulting polymeric phosphonium salt is then deprotonated to form an ylide that undergoes reaction with various aryl aldehydes in a one-pot fashion to yield the respective cinnamates. These materials can undergo further modification through photo-induced [2 + 2] cycloaddition cross-linking reactions.
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- Award ID(s):
- 1847914
- PAR ID:
- 10224206
- Date Published:
- Journal Name:
- Polymers
- Volume:
- 12
- Issue:
- 6
- ISSN:
- 2073-4360
- Page Range / eLocation ID:
- 1247
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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