(452a) Designer 3D Printed Oleophilic Absorbents and Encapsulants with Tunable Capillary Architectures

Here we show how 3D printing can be leveraged to manufacture absorbents with tailored internal oleophilic capillary networks capable of selectively extracting and sequestering oil dispersed in water. These networks are produced using poly(lactic acid), an inexpensive commodity biopolymer that is degradable and environmentally friendly. 3D printing enables designer absorbent architectures to be crafted that match properties of different petroleum fractions, maximize selectivity against water, and permit either strong encapsulation or easy recovery of the collected oil. We describe fundamental characterization studies aimed at identifying optimal pore network architectures that maximize uptake and rate of absorbance, as well as determining quantitative cost/performance metrics for rational selection of optimal designs.

This platform lays a foundation to manufacture a host of products incorporating sophisticated oil absorption and encapsulation functions. We demonstrate this versatility by highlighting two innovative applications. First, we demonstrate the ability to produce large-sized 3D printed absorbent filters that can be incorporated into an autonomous robotic oil skimmer, enabling continuous routine clean-up of waterways. 3D printing makes it possible to overcome the limitations of current sheet or pad-based materials by achieving on-demand rapid production of rugged, reusable, rigid absorbents with superior uptake, selectivity, and ease of deployment. Second, we employ a new family of flexible filaments to produce 3D printed wearable products containing embedded capillary networks tailored to encapsulate oil-based insect repellents. A core-shell design is embedded in a wristband format to uniquely deliver sustained release of dispersed volatile species at higher doses than possible when applied directly to the skin. This approach may offer a new avenue to help combat the spread of mosquito-borne infectious disease.