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Cellulose-based paper is a versatile material with a diverse array of applications. While paper is not commonly thought of as a material that shrinks, here we present a method for miniaturizing paper via periodate oxidation. Chromatography paper was exposed to varying concentrations of periodate (0.1–0.5 M) over a 96-h period. Following optimization of miniaturization parameters, fourteen different types of paper were miniaturized and reductions in surface area ranging from 60 to 80% were observed. All cellulose paper types, but not cellulose-derivatives, displayed successful miniaturization. Results were highly tunable dependent upon periodate concentration and reaction time. Potential applications of the technique are discussed, including its use as a microfabrication method.
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UV‐Micropatterned Miniaturization: Rapid In Situ Photopatterning and Miniaturization of Microscale Features on Shrinkable Thermoplastics
Abstract Shrink lithography is a promising top‐down micro/nanofabrication technique capable of miniaturizing patterns/structures to scales much smaller than the initial mold, however, rapid inexpensive fabrication of high‐fidelity shrinkable microfeatures remains challenging. This work reports the discovery and characterization of a simple, fast, low‐cost method for replicating and miniaturizing intricate micropatterns/structures on commodity heat‐shrinkable polymers. Large‐area permanent micropatterning on polystyrene and polyolefin shrink film is attained in one step under ambient conditions through brief irradiation by a shortwave UV pencil lamp. After baking briefly in an oven, the film shrinks biaxially and the miniaturized micropatterns emerge with significantly reduced surface area (up to 95%) and enhanced depth profile. The entire UV‐micropatterned miniaturization process is highly reproducible and achievable on benchtop under a few minutes without chemicals or sophisticated apparatus. A variety of microgrid patterns are replicated and miniaturized with high yield and resolution on both planar and curved surfaces. Sequential UV exposures enable easy and rapid engineering of sophisticated microtopography with miniaturized, multiscale, multidimensional microstructures. UV–ozone micropatterned polystyrene surfaces are well‐suited for lab‐on‐a‐chip analytical applications owing to the inherent biocompatibility and enhanced surface hydrophilicity. Miniaturization of dense, periodic micropatterns may facilitate low‐cost prototyping of functional devices/surfaces such as micro‐optics/sensors and tunable metamaterials.
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- PAR ID:
- 10457856
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials Technologies
- Volume:
- 5
- Issue:
- 6
- ISSN:
- 2365-709X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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