Robust, notch-insensitive and impact-resistance physical hydrogels with homogeneous topologic network enabled by partial hydrolysis and metal coordination
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引用次数: 0
Abstract
Acrylamide-based hydrogels usually have a random distribution of characteristic functional groups on the molecular chain due to differences in monomer reactivity ratios, resulting in an inhomogeneous polymer network. This inhomogeneity leads to severely inadequate mechanical properties, limiting their application in load-bearing fields. This study delineates a novel approach to synthesize homogeneous hydrogels with enhanced mechanical strength, heightened energy dissipation capacity, and superior impact resistance, termed partially hydrolyzed polymer hydrogels (HP hydrogel). The methodology involves the partial hydrolysis of polyacrylamide in an alkaline environment to convert amide groups into carboxylate groups, followed by the introduction of Fe3+ ions to establish a ligand network through coordination bonding. This partial hydrolysis technique significantly augments the homogeneity of the coordination network. The carboxylate-Fe3+ coordination bonds introduce an efficient energy dissipation mechanism, which is pivotal in enhancing the mechanical robustness of the hydrogels. Comparative analysis reveals that HP hydrogels exhibit mechanical properties substantially superior to those of conventional poly(acrylamide-co-acrylic acid) copolymer hydrogels (CP hydrogel). Notably, the tensile strength of HP hydrogels is quadruple that of CP hydrogels, reaching up to 7.0 MPa, while maintaining the same carboxylic acid content. Furthermore, HP hydrogels demonstrate remarkable tear and impact resistance, evidenced by a fracture energy of 7.5 kJ/m2 in notched specimens and an 85.7% enhancement in impact resilience. The strategic partial hydrolysis not only improves the homogeneity of the gel structure but also instills a robust energy dissipation mechanism, thereby significantly fortifying the comprehensive mechanical properties of the hydrogels. This advancement potentially broadens the applicability of acrylamide hydrogels in load-bearing and other mechanically demanding environments.
期刊介绍:
Polymer is an interdisciplinary journal dedicated to publishing innovative and significant advances in Polymer Physics, Chemistry and Technology. We welcome submissions on polymer hybrids, nanocomposites, characterisation and self-assembly. Polymer also publishes work on the technological application of polymers in energy and optoelectronics.
The main scope is covered but not limited to the following core areas:
Polymer Materials
Nanocomposites and hybrid nanomaterials
Polymer blends, films, fibres, networks and porous materials
Physical Characterization
Characterisation, modelling and simulation* of molecular and materials properties in bulk, solution, and thin films
Polymer Engineering
Advanced multiscale processing methods
Polymer Synthesis, Modification and Self-assembly
Including designer polymer architectures, mechanisms and kinetics, and supramolecular polymerization
Technological Applications
Polymers for energy generation and storage
Polymer membranes for separation technology
Polymers for opto- and microelectronics.