Effect of poly(2‐ethyl‐2‐oxazoline) and UV irradiation on the melt rheology and mechanical properties of poly(lactic acid)

Abstract

To improve the suitability of poly(lactic acid) (PLA) for implantable devices, it ideally needs greater ductility without losses in strength. Here biodegradable poly(2‐ethyl‐2‐oxazoline) (PEtOx) was selected as an additive to improve hydrophilicity of PLA as well as mechanical properties, while UV irradiation was considered as a bulk modification method to increase the long‐term stability. The PLA blend showed improved tensile strength and elongation‐at‐break with small amounts of PEtOx added (1.5 wt %). Crosslinking by UV irradiation showed significant improvements with a dibutyltin dilaurate catalyst even though it produced a high degree of chain scission during melt processing. After UV irradiation for 150 h, the crosslinked material recovered mechanical properties and melt rheological properties comparable to the initial PLA‐1.5%PEtOx blend (without catalyst added). Crosslinking was only possible with the added PEtOx present. A mechanism for the crosslinking reactions examined has been proposed since it has not been previously reported in the literature. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 48023.

An Investigation on the Hardness of Polylactic Acid Parts Fabricated via Fused Deposition Modeling

“…The results found that the interaction of silicon filler in the PLA matrix has a good load-carrying ability, and the PLA with 7% silicon biocomposite has the highest Shore D hardness, attributable to the silicon filler’s load-bearing capacity. Some researchers improve polymer via UV curing or irradiation process, which was considered as a method to increase the long-term stability of polymer [ 28 ]. Lyu et al [ 15 ] added phosphine oxide (XBPO) in the PLA matrix, the results found that the maximum tensile strength of 3D printing specimens increased by 82.5% after UV process.…”

Effects of Printing Temperature and Filling Percentage on the Mechanical Behavior of Fused Deposition Molding Technology Components for 3D Printing

“…Therefore, post-curing technologies have been developed to perform a secondary curing of the molded material through UV light wavelength irradiation to reduce the unevenness between layers and improve the final mechanical properties. This process is however cumbersome and time-consuming [ 14 , 15 ].…”

Effect of addition of triallyl isocyanurate and post‐ultraviolet irradiation on the selected properties of composites of poly(lactic acid), poly(butylene succinate) and nano‐sized calcium carbonate

“…The mechanism and structure of photo-crosslinking of PLA and its model compounds have been reported in the literature. [26][27][28] At the same time, a photo-crosslinking processing technology of PLA and its industrial UVirradiation apparatus have been developed. The major advantages of photo-crosslinking are low cost of the equipment, low energy consumption, easy operating and maintain, high production efficiency, and excellent electronic and mechanical properties.…”

“…In recent years, there has been significant breakthrough in the photo‐initiated crosslinking of bulk PLA. The mechanism and structure of photo‐crosslinking of PLA and its model compounds have been reported in the literature 26–28 . At the same time, a photo‐crosslinking processing technology of PLA and its industrial UV‐irradiation apparatus have been developed.…”