Aminated lignin and phytic acid-assisted polyacrylic acid hydrogel sensors with enhanced mechanical properties and strong adhesion

Int J Biol Macromol. 2024 Nov;280(Pt 2):135944. doi: 10.1016/j.ijbiomac.2024.135944. Epub 2024 Sep 22.

Abstract

Excellent comprehensive performance of hydrogels can be achieved by synergistically combining multiple interaction mechanisms. In this study, a series of hydrogels with rapid gelation and excellent adhesive, mechanical, self-healing, and conductive properties, driven by covalent bonds and multiple reversible interactions, were constructed by mixing acrylic acid (AA), aminated alkaline lignin (AAL), phytic acid (PA), and Fe3+. The rigid skeletons of polyacrylic acid (PAA) and AAL, as well as the metal coordination bonds formed between them and Fe3+, enhance the mechanical properties of the samples. The samples exhibit excellent tensile strength and compressive strength, reaching 73.7 kPa and 4.6 MPa (under a compressive strain of 80 %), respectively, with a tensile strain of 1142 % under the same condition. Adding PA enhances the compliance and adhesion (148.2 kPa for porcine skin) of the gel and endowed it with good flame retardancy. Additionally, the sample maintained its good mechanical properties and conductivity even after five cutting-healing cycles. Good durability, robust adhesion, and high electrical conductivity of the sample render it a promising strain sensor for electronic devices. This work provides a design strategy for preparing hydrogels with superior adhesion and good comprehensive performance.

Keywords: Aminated alkaline lignin; Hydrogel; Phytic acid.

MeSH terms

  • Acrylic Resins* / chemistry
  • Animals
  • Compressive Strength
  • Electric Conductivity
  • Hydrogels* / chemistry
  • Lignin* / chemistry
  • Mechanical Phenomena
  • Phytic Acid* / chemistry
  • Swine
  • Tensile Strength*

Substances

  • Lignin
  • Acrylic Resins
  • Hydrogels
  • carbopol 940
  • Phytic Acid