Hybrid cross-linked poly(2-acrylamido-2-methyl-1-propanesulfonic acid) hydrogels with tunable viscoelastic, mechanical and self-healing properties


Su E., Okay O.

REACTIVE & FUNCTIONAL POLYMERS, vol.123, pp.70-79, 2018 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 123
  • Publication Date: 2018
  • Doi Number: 10.1016/j.reactfunctpolym.2017.12.009
  • Journal Name: REACTIVE & FUNCTIONAL POLYMERS
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.70-79
  • Keywords: 2-Acrylamido-2-methyl-1-propanesulfonic acid, (AMPS), Hydrogels, Laponite, Hybrid-cross-linking, Self-healing, NANOCOMPOSITE HYDROGELS, RADICAL POLYMERIZATION, LAPONITE DISPERSIONS, SWELLING EQUILIBRIA, LIGHT-SCATTERING, FRACTURE, GELS, POLYMERS, MONOMERS, BEHAVIOR
  • Istanbul Technical University Affiliated: Yes

Abstract

Hydrogels derived from 2-acrylamido-2-methyl-1-propanesulfonic acid (AMPS) monomer are attractive materials for producing soft-biomimetic actuators, superabsorbents, and biomaterials. Here we present a simple synthetic strategy to prepare mechanically strong poly(2-acrylamido-2-methyl-1-propanesulfonic acid) (PAMPS) hydrogels with self-healing ability. Initiator-free polymerization of AMPS in aqueous solution in the presence of Laponite nanoparticles and N,N'-methylenebis(acrylamide) (BAAm) cross-linker produces hybrid-cross-linked hydrogels with excellent mechanical properties. The hydrogels exhibit a high modulus (similar to 700 kPa), compressive strength (45 MPa at similar to 90% strain), good resilience, and self-healing. The results reveal that the incorporation of Laponite and BAAm separately into the physical PAMPS network weakens hydrogen bonding interactions while their combination enhances these interactions and generate water-insoluble hydrogels with a high modulus. The superior properties of hybrid cross-linked hydrogels are attributed to strengthening of the interactions between chemically cross-linked PAMPS chains and nanoparticles. The hybrid approach presented here might enable preparation of mechanically strong nanocomposite hydrogels consisting of strongly or weakly charged polymer chains of different architecture.