In order to improve the adhesion of the middle frequency magnetic sputtered zirconium coating on a polyurethane film,an anode layer source was used to pretreat the polyurethane film with nitrogen and oxygen ions.SEMs ...In order to improve the adhesion of the middle frequency magnetic sputtered zirconium coating on a polyurethane film,an anode layer source was used to pretreat the polyurethane film with nitrogen and oxygen ions.SEMs and AFM roughness profiles of treated samples and the contrast groups were obtained.Besides,XPS survey spectrums and high resolution spectrums were also investigated.The adhesion test revealed that ion bombardment could improve the adhesion to the polyurethane coating substrate.A better etching result of oxygen ions versus nitrogen predicts a higher bonding strength of zirconium coating on polyurethane and,indeed,the highest bonding strengths are for oxygen ion bombardment upto 13.3 MPa.As demonstrated in X-ray photoelectron spectroscopy,the oxygen ion also helps to introduce more active groups,and,therefore,it achieves a high value of adhesion strength.展开更多
UV-curable polyurethane prepolymer and photoinitiator 1173 were facilely encapsulated in a poly（urea-formaldehyde） shell, which was in situ formed by the polymerization of formalde-hyde and urea in an oil-in-water e...UV-curable polyurethane prepolymer and photoinitiator 1173 were facilely encapsulated in a poly（urea-formaldehyde） shell, which was in situ formed by the polymerization of formalde-hyde and urea in an oil-in-water emulsion. The diameters of the microcapsules ranged from 118 μm to 663 μm depending on agitation speed, and were obtained via optical mi-croscopy and scanning electron microscopy analyses. The encapsulation percent and the yield of microcapsules prepared at the agitation speed of 600 r/min can reach 97.52wt% and 65.23wt%, respectively. When the water-borne polyurethane （WPU） coating embedded with the prepared microcapsules were scratched, the healing agent could be released from rup-tured microcapsules and lled the scribed region. The excellent anticorrosion properties of the WPU coating embedded with the prepared microcapsules were con rmed by the results obtained from both electrochemical impedance spectroscopy and Tafel curves.展开更多
The changes of the wettability of the solid surfaces have attracted massive attention due to their important practical implications in numerous fields. As a new subject, the research on the wettability under the diffe...The changes of the wettability of the solid surfaces have attracted massive attention due to their important practical implications in numerous fields. As a new subject, the research on the wettability under the different environments is still in its early stage. So the fundamental research must be performed for the practical applications under different environments. However, it is seldom that the comprehensive wettability of a surface in air, in water and in oil has been reported. In this paper, the authors investigated the wettability of the stainless steel mesh coated with polyurethane in the above three different environments. The surface of the uncoated mesh was found to be hydrophobic in air, but the surface of the coated mesh was superhydrophilic in air. More interestingly, the surfaces of the coated meshes were superoleophilic in water and superhydrophobic in oil. Due to the coated meshes with these wettabilities were fabricated via a facile two-step method, the presented method may be adopted for large-scale industrial production, in various fields, such as icing prevention or the oil-field industry.展开更多
文摘In order to improve the adhesion of the middle frequency magnetic sputtered zirconium coating on a polyurethane film,an anode layer source was used to pretreat the polyurethane film with nitrogen and oxygen ions.SEMs and AFM roughness profiles of treated samples and the contrast groups were obtained.Besides,XPS survey spectrums and high resolution spectrums were also investigated.The adhesion test revealed that ion bombardment could improve the adhesion to the polyurethane coating substrate.A better etching result of oxygen ions versus nitrogen predicts a higher bonding strength of zirconium coating on polyurethane and,indeed,the highest bonding strengths are for oxygen ion bombardment upto 13.3 MPa.As demonstrated in X-ray photoelectron spectroscopy,the oxygen ion also helps to introduce more active groups,and,therefore,it achieves a high value of adhesion strength.
文摘UV-curable polyurethane prepolymer and photoinitiator 1173 were facilely encapsulated in a poly（urea-formaldehyde） shell, which was in situ formed by the polymerization of formalde-hyde and urea in an oil-in-water emulsion. The diameters of the microcapsules ranged from 118 μm to 663 μm depending on agitation speed, and were obtained via optical mi-croscopy and scanning electron microscopy analyses. The encapsulation percent and the yield of microcapsules prepared at the agitation speed of 600 r/min can reach 97.52wt% and 65.23wt%, respectively. When the water-borne polyurethane （WPU） coating embedded with the prepared microcapsules were scratched, the healing agent could be released from rup-tured microcapsules and lled the scribed region. The excellent anticorrosion properties of the WPU coating embedded with the prepared microcapsules were con rmed by the results obtained from both electrochemical impedance spectroscopy and Tafel curves.
基金supported by the National Natural Science Foundation of China(Grant Nos.51475353,51375361&51475352)the Tribology Science Fund of the State Key Laboratory of Tribology(Grant No.SKLTKF14A02)+1 种基金the Natural Science Basic Research Program of Shaanxi Province(Grant No.2016JM5004)the Key Laboratory of the Shaanxi Provincial Department of Education(Grant No.16JS057)
文摘The changes of the wettability of the solid surfaces have attracted massive attention due to their important practical implications in numerous fields. As a new subject, the research on the wettability under the different environments is still in its early stage. So the fundamental research must be performed for the practical applications under different environments. However, it is seldom that the comprehensive wettability of a surface in air, in water and in oil has been reported. In this paper, the authors investigated the wettability of the stainless steel mesh coated with polyurethane in the above three different environments. The surface of the uncoated mesh was found to be hydrophobic in air, but the surface of the coated mesh was superhydrophilic in air. More interestingly, the surfaces of the coated meshes were superoleophilic in water and superhydrophobic in oil. Due to the coated meshes with these wettabilities were fabricated via a facile two-step method, the presented method may be adopted for large-scale industrial production, in various fields, such as icing prevention or the oil-field industry.
