Construction of superhydrophobic surfaces with tunable adhesion force has attracted considerable attention in past decades. Here, we demonstrated an exfoliated surface in non-solvent-coated poly(lactic acid) (PLA) films which exhibited controllable domain morphology containing "face-on", "edge-on" or "peak-on" nano-/micro-structures. A theoretical understanding revealed that such controllable morphology responded closely to the variation in mixture viscosities at a fixed temperature.Furthermore, the resulting films were highly superhydrophobic with contact angles >150. In particular, adhesion could be tuned ranging from 144 mN to 62 mN for face-on and peak-on surfaces, respectively, by changing the non-solvent content. This strategy allowed for high-efficiency and high-precision transportation of water microdroplets (1 mL) with a yield of #100% on homogeneous surfaces. This approach could aid no-mass-lost fluid transportation for a broad variety of applications in bioengineering and biochips.

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Porous poly (l‐lactic acid) (PLLA) sponges have received rapid development in the materials science and energy fields due to their good biocompatibility and degradability. Herein, hierarchical micro‐/nano‐structures of PLLA sponges are successfully prepared by the microphase separation method to investigate the influence of non‐solvents on PLLA microtopography. The interaction ability between PLLA and various alcohol non‐solvents is precisely calculated by using the Flory–Huggins equation. SEM results show that the porosity of PLLA surfaces increases with increasing non‐solvent solubility parameters at a certain range. When the solubility parameters of alcohol non‐solvents are much higher than that of PLLA, PLLA bulks accumulate on the surfaces, mainly caused by its insolubility. DSC curves disclose that the crystallinity has a positive relationship with contents and solubility parameters of alcohol non‐solvents. Furthermore, these porous PLLA surfaces show strong water repellency and self‐cleaning ability so that the contaminant can be quickly cleared away from the PLLA surfaces. This study provides a new insight into understanding the formation process of PLLA porous materials and the wetting variation for high‐efficiency self‐cleaning.

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Triple one‐way and two‐way shape memory polymers (1W‐SMPs and 2W‐SMPs) are highly desirable for many practical applications due to the multiple shape transformation. In this work, the blend with co‐continuous structure is fabricated based on poly(ethylene‐co‐vinyl acetate) (EVA) and poly(ε‐caprolactone) (PCL), which shows excellent triple one‐way and two‐way shape memory properties. It is found that the blends have two independent crystallization peaks and two independent melting peaks. With the increase of dicumyl peroxide (DCP) content, the crystallization temperature, melting temperature, and crystallinity of both EVA and PCL in the blends gradually decreases. The blends show great dual and triple one‐way shape memory property, and the phenomena of elongation induced by oriented crystallization and contraction induced by melting are clearly seen. Moreover, the blends exhibit remarkable and recyclable triple two‐way shape memory performance, with an average shape recovery magnitude of 97.3% and an average actuation magnitude of 50.6%. In terms of the excellent triple one‐way and two‐way shape memory performance, the EVA/PCL blends may have potential applications in the fields of soft robotics, actuators, and cranes. The new preparation method of triple 2W‐SMPs can be used to fabricate other triple 2W‐SMPs with commercial polymers.