Biofouling at the solid–liquid–air interface poses a serious threat to public health and environmental sustainability. Despite the variety of antifouling materials developed, few have proven to resist fouling at the three‐phase contact line. In fact, antifouling at the liquid–solid interface and the air–solid interface call for opposite surface properties—hydrophilic for the former and hydrophobic for the latter. By devising a new design strategy, one that maximizes the mismatch of surface energies of comonomers for dynamic chain reorientation at the three‐phase contact line, an antifouling amphiphilic copolymer is obtained. The novel amphiphilic copolymer reduces the formation of biofilms by
- PAR ID:
- 10427086
- Date Published:
- Journal Name:
- ACM Transactions on Graphics
- Volume:
- 41
- Issue:
- 6
- ISSN:
- 0730-0301
- Page Range / eLocation ID:
- 1 to 15
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract Pseudomonas aeruginosa and outperforms a zwitterionic polymer, the current leading antifouling chemistry. The copolymer is synthesized using initiated chemical vapor deposition (iCVD), which leads to molecular‐level heterogeneities composed of zwitterionic and fluorinated moieties by avoiding undesirable surface tension effects. Atomic force microscopy, x‐ray diffractometry, and Fourier transform infrared spectroscopy confirm the copolymer's amphiphilicity and lack of microphase separation. Scanning electron microscopy provides visual confirmation of the diminished biofilm growth. The versatile iCVD technique is amenable to a range of substrates and enables the application of this new material to food processing, healthcare, and underwater performance. -
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Abstract Frosting occurs due to the freezing of condensed water droplets on a supercooled surface. The nucleated frost propagates through interdroplet bridges and covers the entire surface, resulting from the deposition of highly supersaturated vapor surrounding tiny droplets. While inhibition of the formation of frost bridges is not possible, the propagation of frost can be delayed by effectively removing tiny droplets. Passive technologies, such as superhydrophobic surfaces (SHS) and hydrophobic slippery liquid‐infused porous surfaces (SLIPS), rely on static growth and direct contact with densely distributed droplets. However, use of these approaches in delaying frost propagation involves challenges, as the interdroplet distance remains small. Here, we report a new approach of spontaneous droplet movement on hydrophilic SLIPS to delay the formation of interdroplet frost bridges. Surface tension forces generated by the hydrophilic oil meniscus of a large water droplet efficiently pull neighboring droplets with a diameter of less than 20 μm from all directions. This causes a dynamic separation between water droplets and an adjacent frozen droplet. Such a process delays the formation and propagation of interdroplet frost bridges. Consequently, there is significant delay in frosting on hydrophilic SLIPS compared to those on SHS and hydrophobic SLIPS.
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Abstract In this article, we propose a novel hybrid framework by combining smoothed particle hydrodynamics and adaptive narrow band fluid implicit particle method (NB‐FLIP) to faithfully model the multiphysical processes involving heat transfer and phase transition, and to precisely simulate the dynamics of condensed droplets moving along intricate objects. We first formulate a governing physical model built upon an improved phase transition model and an augmented on‐surface drop analysis method to achieve realistic condensation effects over intricate hydrophilic/hydrophobic interface. To achieve both high‐fidelity interactions and high‐resolution visual effects, we further develop an adaptive NB‐FLIP solver with octree‐dictated background grid in order to further enhance the performance of our framework. Experimental results have shown that our approach can be used to efficiently and realistically simulate the small‐scale interaction details between condensed drops and complex objects with arbitrary geometry.
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1145/3550454.3555478
