ZnO micro-nano composite hydrophobic film prepared by the three-step method

The hydrophobicity of the lotus leaf is mainly due to its surface micro-nano composite structure. In order to mimic the lotus structure, ZnO micro-nano composite hydrophobic films were prepared via the three-step method. On thin buffer films of SiO2, which were first fabricated on glass substrates by the so,gel dip-coating method, a ZnO seed layer was deposited via RF magnetron sputtering. Then two different ZnO films, micro-nano and micro-only flowerlike structures, were grown by the hydrothermal method. The prepared films have different hydrophobic properties after surface modification. The structures of the obtained ZnO films were characterized using x-ray diffraction and field-emission scanning electron microscopy. A conclusion that a micro-nano composite structure is more beneficial to hydrophobicity than a micro-only structure was obtained through research into the effect of structure on hydrophobic properties.

Inhibiting water evaporation of sandy soil by the soil particles modified with Japanese wax

This study was conducted to resolve the problems of water conservation of sandy soil in desertification areas. The surface of soil particles was modified by molecules of natural Japanese wax through some specially screened surfactant. The modified particles were then well sprayed onto the sand, which was placed in an artificial climate box with simulating desert environment, to form a soil film with effect of suppressing water and gas-permeability. Structure of soil film was analyzed by means of X-ray diftYaction （XRD） and infrared spectrometry （IR）. And its mechanism of water inhibition was illustrated with DSC and TG curves. Its influence on grass-planting was tested through the instruments of water detector. The results show that sorbitol anhydride stearate （ Span 80） could well disperse the Japanese wax and make it combine with the clay which is also dispersed. The pores among soil particles grew smaller and turned from hydrophilic into hydrophobic, in which way resistance to water penetrating through the film was increased. Experimental grass grows normally on sandy soil with the soil film in the artificial desert climate box, indicating that the soil particles modified with Japanese wax is an effective method to inhibit water evaporation.

Multi-fluorous-included Counter Anions-based Ionic Copolymers:Synthesis and Enhanced Hydrophobic Adsorption Films on Copper Surface for Super Protection

Three multi-fluorous-carried anions-based ionic copolymers(ICs)including(fluorosulfonyl)imide(FSI-),(trifluorometha-nesulfonyl)imide(TFSI-)and hexafluorophosphate anions(PF6-)(IC[FSI-]),poly[1,1'-(butane-1,4-diyl)bis(3-pentyl-1H-imidazol-3-ium)bis(fluorosulfonyl)amide](IC[TFSI-]),poly{1,1'-(butane-1,4-diyl)bis(3-pentyl-1H-imidazol-3-ium)bis[(trifluoromethyl)sulfonyl]-amide}(IC[PF6-]),poly[1,1'-(butane-1,4-diyl)bis(3-pentyl-1H-imidazol-3-ium)bishexafluorophosphate]were synthesized with a simple ionic exchange method by using amphiphilic poly[1,1'-(butane-1,4-diyl)bis(3-pentyl-1H-imidazol-3-ium)bisbromide](IC[Br-])as the intermediate ionic polymer.The chemical srutrcures of the target ICs were characterized by nuclear magnetic resonance(NMR)spectroscopy and Fourier-transform infrared spectroscopy(FTIR).It is shown that the target ICs could be spontaneously adsorbed on copper surface in N,N-dimethflormamide(DMF),and the tight adsorption films were formed on metal surface.The contacting angles suggest that the formed adsorption layers of target ICs on copper surface were characterized with hydrophobic nature.Furthermore,the target ICs-copper chemistry bonding was confirmed by various means.The electrochemistry analysis showed that the target ICs adsorption layers could prevent from copper corrosion in H2SO4solution efficiently,and the maximal anticorrosion efficiency was over 95%at 0.100 g/L.In particular,the target ICs showed 85%or above anticorrosion efficiency for copper at a low concentration of 0.025 g/L,which was greater than the intermediate polymer IC[Br-].In addition,an insight of mixed chemisorption and physisorption of the target ICs on metal surface was analyzed and discussed.

Effect of Hydrophobic Modification on the Durability and Environmental Properties of Porous MgF_2 Antireflective Films

Conventional porous MgF2 antireflective films show poor environmental durability due to its hydrophilic nature.To improve the film environmental durability,hydrophobic porous MgF2 antireflective films are prepared by a methyl silicone-modified MgF2 sol.Effects of the methyl silicone proportions on the film properties are examined in order to control the wettability,peak transmittance,and environmental durability of the films.The modification of methyl silicone can increase the film hydrophobicity,thus decreases the adsorption of water,and improves the environmental durability.However,large amounts of methyl silicone could increase the film refractive index,resulting in the decrease in peak transmittance for films on BK7 glass.Films with 40% silicone show water contact angle of 110°,peak transmittance of 98.7%,and good environmental durability.The results of accelerated test show that the environmental durability of the porous MgF2 films modified with 40% methyl silicone is six times higher than that of the conventional films.

Synthesis, UV-curing Behavior and Surface Properties of Fluorinecontaining Vinyl Ether Polymers

Five fluorine-containing vinyl ether monomers were prepared by the reaction between 2-vinyloxy ethanol, a fluorinated alcohol and hexafluorobenzene in the presence of sodium hydride in dimethylformamide. Two representative properties of these monomers, UV-curing behavior initiated by a cationic photo-initiator PAG 201 and surface free energy of coating films, were investigated. Photo-polymerization proceeded both rapidly and completely with a high double-bond conversion （〉 90%） and a fast curing rate （maximum curing time 〈 21 s） for three monomers. The surface energies of the monomers and the resulting polymer films were then investigated. The minimum surface free energy of the UV-cured homopolymer films reaches 7.1 mJ/m2. X-ray photoelectron spectroscopy data show that the low surthce tension is influenced by fluorine content in the soft segments and fluorinated chains＇ migration to the surface. The five monomers exhibit low viscosity, low surface energy, good thermal stability and good photo-polymerization properties, which make them great candidates for UV coating and photoresist applications.