Hai Yun Jiang

Fabrication of a Super-Hydrophobic Micro-Nanoporous Aluminum Surface by Anodic Oxidation

A novel and stable super-hydrophobic film was prepared by stearic acid (C18H36O2), which was chemically adsorbed onto the anodized aluminum surface. The maximum static water contact angle (WCA) of the super-hydrophobic surface was 157.5º ± 2.0º and the contact angle hysteresis was less than 3º. The superhydrophobic property is attributed to the micro-nanoporous surface morphology and stearic acid. The pore size on the surface of anodic aluminum oxide is an important factor for controlling the superhydrophobic adhesiveness. The superhydrophobic surface is a factor to reduce device-associated infection and can be used in metal packaging practice.

Effects of Oxalic Acid and Sodium Chloride on the Superhydrophobic Surface on Aluminum Alloy by Anodizing and PP-Coating

We investigated the preparation of the superhydrophobic surface on aluminum alloy by anodizing and PP coating. The effects of oxalic acid and sodium chloride in the electrolytic cell on the superhydrophobic surface were discussed. The results showed that a good superhydrophobic surface was achieved by direct PP coating after anodizing. The addition of oxalic acid had a little enhanced effect on the superhydrophobic surface, while the addition of sodium chloride had an obvious effect on the superhydrophobic surface. When the concentration of NaCl was 1.25 g/L, the contact angle (CA) was up to 162 ° and the sliding angle was lower than 3 ° .

Anti-Icing Properties of Superhydrophobic poly (vinyl chloride) Coatings

In this work, the anti-icing properties of different poly (vinyl chloride) coatings with different wettabilities were investigated in a climatic chamber with a working temperature of −10 °C. Compared with smooth poly (vinyl chloride) coating, the superhydrophobic poly (vinyl chloride) coating with high sliding angle did not show obvious anti-icing property. However, the superhydrophobic poly (vinyl chloride) coating with low sliding angle can largely prevent ice formation on the surface, showing excellent anti-icing property.

Bacteriostasis of a Super-Hydrophobic Micro-Porous Aluminum Surface by a Facile Preparation Method

We investigated the bacteriostasis of the super-hydrophobic surface on aluminum alloy by PP coating. The morphology of the surface was observed by a scanning electron microscopy. The contact angle (CA) was measured by an optical contact angle meter .Staphylococcus aureus and pathogenic escherichia coli adhesion on superhydrophobic surfaces were also evaluated. The inhibition ring test results show the inhibition of Escherichia coli and Staphylococcus aureus were 79.3% and 81.1%, respectively after 24 hours’ contact at 37oC, while the Quinn test demonstrates the surface possesses high resistance to bacterial contamination. The superhydrophobic surface is a factor to reduce device-associated infection and can be used in metal practice.

Fabrication of a Superhydrophobic Aluminum Alloy Surface by Phosphoric Acid-Dichromate Method

The preparation method of the superhydrophobic surface on aluminum alloys was investigated, the method is novel by phosphoric acid-dichromate process and stearic acid coating, superhydrophobic aluminum alloy surfaces were successful prepared, the maximum static water contact angle and sliding angle on the superhydrophobic surface was 151±1.8° and 10°, respectively. In this work, the microstructure and self-cleaning properties of the superhydrophobic surface were studied. The superhydrophobic surface is a factor to reduce device-associated contamination and can be used in metal packaging practice.

Superhydrophobic Film Make up of Corrosion Aluminum Plates and Polypropylene Coated

Polypropylene (PP) film was used as coating to improve the hydrophobicity of corrosive aluminum surface. A micro-porous film with compound nanoparticles was obtained on the aluminum alloy substrate using the corrosion method and coated PP. The water contact angle (WCA) of superhydrophobic surface is 157°. The superhydrophobic property is attributed to this special surface morphology and low surface energy PP. Aggregated nanoparticles would help to increase the surface hydrophobicity.

A Novel Preparation of Porous Superhydrophobic Polystyrene/Poly (vinyl chloride) Composites Film

Inspired by the “lotus effect”, a porous superhydrophobic PS/PVC composites film comprised of many micro-spheres and nanofibers was obtained by a simple approach. These micro-spheres were interlinked with nano-fibers. The sizes of the micro-spheres were 0.6-3 µm, and the diameters of these nano-fibers were between 100-600 nm. The water contact angle and sliding angle on the superhydrophobic film were 155±1.8ºand 3º, respectively. When water flowed through the PS/PVC composites film for 2 h, no water bead was adhered on the superhydrophobic PS/PVC composites film, and the contact angle value was remained about 155°. Moreover, the contact angle were still higher than 150° when contacting with water with the temperatures ranging from 10°C to 60°C. The surface morphology of the PS/PVC composites film can be adjusted by changing the addition of PVC.

Some Observations on Dynamical Cushioning Property of Overlay Cushion Combined with Dissimilar Materials

Honeycomb fiberboard, polyethylene foam, and polystyrene foam were used to manufacture overlay cushion. The corresponding dynamical cushioning property was investigated including the effects the overlay sequence, drop height, join mode, and the thickness difference of both buffer layers. The results indicated the overlay cushion kept a relative high cushioning property when the “soft” buffer layer was directly contacted with the impact rammer. However, the result may be in reverse without adhesion. At the same time, the excessive difference of cushioning property between both the buffer layers was not beneficial to exertion of overlay cushion. Besides, this difference would be scaled up with increase of thickness difference of both the buffer layers.

Facile Preparation of the Superhydrophobic Surface on Aluminum Alloy by PP-Coating

We investigated the preparation of the superhydrophobic surface on aluminum alloy by PP coating. The effects of PP concentration and duration on the surface were discussed. The contact angle (CA) was measured by an optical contact angle meter and the morphology of the surface was observed by a scanning electron microscope. The result showed that the superhydrophobic surface on aluminum alloy could be facilely fabricated by direct PP coating with a suitable concentration. It was confirmed by SEM that the superhydrophobic surface was resulted from the micro/nano-structure of PP. However, the CA became much lower as time went on. It was indicated that the duration of the superhydrophobic surface on aluminum alloy by direct PP coating was poor and a suitable method for improving the duration should be adopted.

Packaging Properties of Composite Film Made up of Polylactic Acid (PLA) and Triacetin

Triacetin (TAC) was used as plasticizer to improve the ductile of polylactic acid (PLA). A composite film composed of PLA and TCA was therefore Paraed, and the packaging properties of this film were tested including the elongation, tensile strength, tear strength, Transparency and permeability. The results suggest that the film owns superior synthetically packaging properties when the proportion of TAC is 30 % (mass ratio). At the same time, this film has a low gas barrier which is especially for the package of the novel vegetable and fruits.