Highly stretchable and thermally healable polyampholyte hydrogels via hydrophobic modification


Toleutay G., Su E., Kudaibergenov S., Okay O.

COLLOID AND POLYMER SCIENCE, vol.298, pp.273-284, 2020 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 298
  • Publication Date: 2020
  • Doi Number: 10.1007/s00396-020-04605-8
  • Journal Name: COLLOID AND POLYMER SCIENCE
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, PASCAL, Chimica, Compendex, EMBASE, INSPEC
  • Page Numbers: pp.273-284
  • Keywords: Hydrogels, Polyampholytes, Hydrophobic interactions, Mechanical properties, Temperature-induced healing, SELF-HEALING HYDROGELS, SHAPE-MEMORY HYDROGELS, MULTIPLE PHASES, POLYACRYLAMIDES, BEHAVIOR, POLYELECTROLYTE, TOUGH
  • Istanbul Technical University Affiliated: Yes

Abstract

Aqueous solutions or gels of polyampholytes attract interest for more than half a century due to their several attractive properties. We present here thermally healable hydrophobically modified physical polyampholyte (PA) hydrogels based on oppositely charged 2-acrylamido-2-methylpropane-1-sulfonic acid sodium salt (AMPS) and (3-acrylamidopropyl) trimethylammonium chloride (APTAC) monomers. PA hydrogels were prepared via micellar polymerization technique in the presence of the hydrophobic monomer n-octadecyl acrylate (C18A) in aqueous sodium dodecyl sulfate (SDS) solutions. Charge-balanced PA hydrogels containing 60-90% water exhibit a high tensile strength and stretchability of up to 202 kPa and 1239%, respectively. Above 7 mol% C18A, swollen hydrogels containing around 90% water exhibit much better mechanical properties as compared with the corresponding as-prepared ones because of the stronger hydrophobic interactions in the absence of SDS micelles. Cut-and-heal tests conducted at 50 degrees C reveal a complete healing efficiency with respect to Young's modulus for all as-prepared PA hydrogels within 1-4 h.