On the basis of ‘well-ordered polymer nano-fibers by external mac

On the basis of ‘well-ordered polymer nano-fibers by external macroscopic force (F blow) interference’ as Natural Product Library supplier mentioned above, the method and mechanism for orderly nano-fibers/spheres by internal microscopic force interference during the crystallization process in different cooling mediums (cooling rate) have been further systematically investigated in this work.Figure  4 shows the surface morphology of the PTFE/PPS superhydrophobic coatings fabricated by quenching Veliparib cost in different uniform cooling mediums after curing at 390°C for 1.5 h: Q1 coating was quenched in the air

at 20°C, while Q2 coating was quenched in the mixture of ethanol and dry ice at -60°C. The surface of Q1 coating also exhibits porous gel network and micropapillae structure similar with P2 coating. In addition, relatively smaller PTFE nano-spheres and papules (80 to 200 nm in diameter) were distributed uniformly and consistently on the smooth continuous surface of the micropapillae and isolated islands, as shown by the continuous zone in Figure  4b. The tangled nano-willow and nano-fiber segments were scattered on the interface surface (discontinuous zone) of the gel network and micropapillae phase (Figure  4c). Both nano-willow and nano-fiber segments are approximately 1 μm in length and 100 to 500 nm in width (Figure  4c). Q2 coating exhibits similar microstructure with Q1 coating, which is shown in Figure  4. Moreover, more uniform,

dense nano-spheres and papules (approximately 60 to 150 nm in diameter) were distributed on the continuous surface of micropapillae with a relatively higher degree FRAX597 ic50 of overlap in comparison to Q1 coating (Figure  4d,e). Besides, shorter and wider nano-fiber segments with 100 to 500 nm in length Tyrosine-protein kinase BLK and 200 to 400 nm in width were distributed on the rough discontinuous surface (Figure  4d,f). In addition, such MNBS texture leads to superhydrophobicity for Q1 and Q2 coating with a WCA of

158° and 153°, respectively.Furthermore, Q3 coating was hardened in the non-uniform cooling medium (pure dry ice media) at -78.5°C after curing at 390°C for 1.5 h. It can be seen that the surface of Q3 coating exhibits similar porous gel network and micropapillae structure (Figure  5a) with P2, Q1, and Q2. In addition, the PTFE nano-spheres, with 20 ~ 100 nm in diameter, were distributed most uniformly, consistently, and densely on the smooth continuous surface (continuous zone) of the micropapillae (Figure  5a,b,c). However, obvious cracks and gaps appeared on the discontinuous interface (discontinuous zone) of the gel network and micropapillae (Figure  5a,d). New polymer nano-wires were generated at the cracks or gaps between the micropapillae (Figure  5e,f,g,h). The length and width of the polymer nano-wires range from 1 to 8 μm and 10 to 80 nm, respectively. Moreover, the long PTFE nano-wires were tightly bonded on respective walls in gap forming nano-bridges (Figure  5e,f,g,h).

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