Autonomic self-healing in covalently crosslinked hydrogels containing hydrophobic domains


POLYMER, vol.54, no.23, pp.6381-6388, 2013 (Peer-Reviewed Journal) identifier identifier

  • Publication Type: Article / Article
  • Volume: 54 Issue: 23
  • Publication Date: 2013
  • Doi Number: 10.1016/j.polymer.2013.09.051
  • Journal Name: POLYMER
  • Journal Indexes: Science Citation Index Expanded, Scopus
  • Page Numbers: pp.6381-6388


Self-healing hydrogels suffer from low mechanical strength due to their reversible breakable bonds which may limit their use in any stress-bearing applications. This deficiency may be improved by creating a hybrid network composed of a combination of a physical network formed via reversible crosslinks and a covalent network. Here, we prepared a series of hybrid hydrogels by the micellar copolymerization of acrylamide with 2 mol % stearyl methacrylate (C18) as a physical crosslinker and various amounts of N,N'-methylenebis(acrylamide) (BAAm) as a chemical crosslinker. Rheological measurements show that the dynamic reversible crosslinks consisting of hydrophobic associations surrounded by surfactant micelles are also effective within the covalent network of the hybrid hydrogels. A significant enhancement in the compressive mechanical properties of the hybrid gels was observed with increasing BAAm content. The existence of an autonomous self-healing process was also demonstrated in hybrid gels formed at low chemical crosslinker ratios. The largest self-healing efficiency in hybrids was observed in terms of the recovered elastic modulus, which was about 80% of the original value. (C) 2013 Elsevier Ltd. All rights reserved.