Tunable hydrogels have gained significant attention in the bioengineering field due to their designer preparation approach. Towards this end, gelatine stands out as a promising candidate owing to its desirable attributes, such as biocompatibility, ability to support cell adhesion and proliferation, biodegradability, and cost-effectiveness. This study presents the preparation of a robust gelatine hydrogel employing sacran aldehyde (SDA) as a natural cross-linker. The resulting SDA-cross-linked gelatine hydrogels (GSDA) display an optimal compressive stress of 0.15 MPa at 50% strain, five times higher than pure gelatine hydrogel. As SDA cross-linking concentration is increased, the swelling capacity of GSDA declines. This decline in swelling capacity, from 80% to 40%, is a result of strong crosslinking of gelatin with SDA. Probing further with FT-IR spectroscopy and SEM at the micron scale unveiled a dual-cross-linking mechanism within the hydrogels. This mechanism encompasses both short- and long-range covalent cross-linking, along with thermo-induced physical cross-linking, resulting in a significant enhancement of the load-bearing capacity of the fabricated hydrogels.

Tunable hydrogels have gained significant attention in the bioengineering field due to their designer preparation approach. Towards this end, gelatine stands out as a promising candidate owing to the desirable attributes, such as biocompatibility, ability to support cell adhesion and proliferation, biodegradability, along with being cost-effective. This study presents the preparation of a robust gelatine hydrogel employing sacran dialdehyde (SDA) as a natural crosslinker. The resulting SDA-crosslinked gelatine hydrogels (GSDA) display an optimal compressive stress of 0.15 MPa at 50% strain, five times higher as compared to pure gelatine hydrogel. As SDA crosslinking concentration is increased, swelling capacity of GSDA declines. Probing further with FTIR spectroscopy and SEM at the micron-scale unveiled a dual-crosslinking mechanism within the hydrogels. This mechanism encompasses both short- and long-range covalent crosslinking, along with thermo-reversible physical crosslinking, resulting in a significant enhancement of the load-bearing capacity of the fabricated hydrogels.

With the depletion of high-grade ores and increasing demand for critical minerals, more efficient and sustainable mineral processing methods are needed. The loss of valuable fine mineral particles to tailings due to inefficient recovery by traditional flotation remains a critical challenge. In this research, novel emulsion binders were developed and evaluated for a rapid agglomeration approach to enhance the capture of fine hydrophobic particles below the optimal flotation size range. High Internal Phase (HIP) water-in-oil (w/o) emulsions stabilised by four novel polyethylene glycol-based amphiphilic polymers synthesised via RAFT polymerisation were tested for agglomeration and recovery of naturally hydrophobic talc particles (mean size 17.5 µm) using a 100 – 180 µm sieve system. Benchmark comparisons were performed using HIP traditional emulsions stabilised with Span® 80 (sorbitan monooleate), a previously reported poly(N-isopropyl acrylamide) (PNIPAM) block copolymer surfactant, and plain kerosene oil. One polymer was further explored, stabilising emulsions containing 0.12 volume fraction of kerosene oil and up to 88 vol.% of 3 wt% NaCl aqueous solution, with polymer concentrations of 0.5 - 2.5 wt%. These binders (in 5-25 g doses) were evaluated in rapid agglomeration experiments, while plain oil was limited to 6 g. The novel binders outperformed the benchmarks overall, achieving over 90 wt% particle recovery and reducing the organic liquid requirement up to 10-fold compared to plain oil. Additionally, emulsions aged for 28 days retained good agglomeration capability, particularly at higher polymer concentrations. These results demonstrate the potential of polymer-stabilised HIP emulsions to improve fine mineral processing.