Thermoresponsive self-assembled NiPAm-zwitterion copolymers

Ya Zhao, Tao Bai, Qing Shao, Shaoyi Jiang, Amy Q. Shen

Research output: Contribution to journalArticlepeer-review

43 Scopus citations


Zwitterionic polymers are well known for their non-fouling properties due to their unique pendant side chain structures. In this work, we incorporated temperature-responsive N-isopropylacrylamide (NiPAm) with zwitterionic monomers (carboxybetaine methacrylate (CBMA) and sulfobetaine methacrylate (SBMA)), and synthesized the statistical copolymers poly(NiPAm-co-CBMA) and poly(NiPAm-co-SBMA). Above the low critical solution temperature (LCST), a clear sol-gel transition was observed, accompanied by an increase in the turbidity and elastic modulus of the copolymer solution. The self assembly and thermoresponsive properties of these statistical copolymers under large strains and different temperatures were characterized by UV-visible spectroscopy, dynamic light scattering, and rheological characterizations. We showed that poly(NiPAm-co-CBMA) copolymers consisted of both mechanically and thermally reversible networks, favoring them as reusable and biocompatible elastic materials. As a comparison, incorporating SBMA with NiPAm inhibited the thermo-sensitive and viscoelastic features of the pure NiPAm based polymer, causing a delayed LCST and a weakened viscoelastic response in poly(NiPAm-co-SBMA) copolymers at both room and body temperatures. Our work demonstrates that CBMA monomers in a poly(NiPAm-co-CBMA) copolymer act as stronger ionic bridges to form elastic networks when compared with a poly(NiPAm-co-SBMA) copolymer. As a result, poly(NiPAm-co-CBMA) possesses both non-fouling and thermo-sensitive features, without compromised mechanical properties. This journal is

Original languageEnglish (US)
Pages (from-to)1066-1077
Number of pages12
JournalPolymer Chemistry
Issue number7
StatePublished - Feb 21 2015

ASJC Scopus subject areas

  • Bioengineering
  • Biochemistry
  • Polymers and Plastics
  • Organic Chemistry


Dive into the research topics of 'Thermoresponsive self-assembled NiPAm-zwitterion copolymers'. Together they form a unique fingerprint.

Cite this