Master of Science (MS)
Chemical and Materials Engineering
Chemical engineering; Materials Science
Additive manufacturing, otherwise known as 3D printing, is an emerging technology with wide applications. The goal of this work is to study hydrogels comprised of the poly(isopropyl glycidyl ether-block-polyethylene glycol-block-isopropyl glycidyl ether) triblock copolymer, poly(iPrGE-PEG-iPrGE), for 3D printing. The hydrogel blends contain poly(iPrGE-PEG-iPrGE) along with varying concentrations of 2.5k PEG, 4k PEG, 8k PEG, 18.5k PEG or 2.5k iPrGE homopolymers. The effectiveness of the blends was measured by comparing the gel point, storage modulus, equilibrium modulus, and yield stress of the hydrogels. The average gel point for the samples ranged from 7.03-12.78 °C and the hydrogels were thermoreversible. The concentration of the triblock was the biggest contributor for differences in the gel point. All of the hydrogels exhibited non-Newtonian shear-thinning properties as well as the ability to recover strength following a period of high strain. The 1 and 5% iPrGE hydrogel blends were the strongest hydrogels, based on the equilibrium modulus and yield stress at room temperature. However, due to interactions in the hydrophobic domain, iPrGE hydrogels had the smallest temperature range and exhibited syneresis at lower temperatures compared to other hydrogel blends. Triblock hydrogels were successfully created and tuned to different levels of strength through the addition of homopolymer.
Le, Alexander B., "Tuning Poly(Isopropyl Glycidyl Ether-block-Polyethylene Glycol-block-Isopropyl Glycidyl Ether) Poly(iPrGE-PEG-iPrGE) Triblock Hydrogels for Use in 3D Printing" (2021). Master's Theses. 5235.