Speaker
Description
All-purpose polymers are extensively used in many applications fields such as packaging, biomaterials, microelectronic devices and thin-film technology due to their combination of low-density, flexibility, ease of processing and low processing costs [1]. Many novel processing strategies to control the wettability characteristics of polymeric surfaces have been devised in the last years, allowing advanced liquid manipulation and paving the way for new applications [2,3]. In this contribution, a two-step approach to fabricate periodic microstructures on polyethylene terephthalate (PET) and poly(methyl methacrylate) (PMMA) foils to increase their hydrophobicity is presented. Periodic micropillars with spatial periods between 1.6 and 4.6 µm were replicated by plate-to-plate hot embossing from chromium stamps previously structured by four-beam Direct Laser Interference Patterning (DLIP). The stamps were processed with different set of DLIP parameters such as fluence, overlapping angle and number of applied pulses, to obtain microtextures with different geometries, spatial periods and structure heights. The wettability properties, namely the static, advancing/receding contact angles (CAs), and contact angle hysteresis, of the patterned PET and PMMA surfaces were characterized. The results indicated that the micropillar arrays induced a hydrophobic state in both polymers with CAs up to 140° in the case of PET. Additionally, the structured surfaces showed a high adhesion to water, as the droplets sticked to the surfaces for tilting angles up to 90°.
References
[1] Hegemann D et al. Nucl. Instrum. Methods B 208 281–6 (2003).
[2] Lee W et al. Langmuir 20 7665–9 (2004).
[3] Molinuevo J et al. Procedia CIRP 94 885–90 (2020).
| Speaker Country | Germany |
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