Preparation of aluminum oxide-coated carbon nanotubes and the properties of composite epoxy coatings research

Abstract

Multiwalled carbon nanotubes (MWCNTs) were acidized to get MWCNTs-COOH; the aluminum oxide (Al 2 O 3 )-coated MWCNTs hybrid material were prepared by sol-gel method and the result of cladding was verified using x-ray diffraction and scanning electron microscopy. Silane-coupling agent (KH560) was used to modify the hybrid materials. Composite coating with different concentrations of MWCNTs and Al 2 O 3 -coated MWCNTs was prepared. The wear resistance of the composite coating was tested by wear tester. The impedance performance and flexibility of Al 2 O 3 -coated MWCNTs/epoxy (2 wt%) and MWCNTs/epoxy (2 wt%, composite coating containing 2 wt% nanometer powder) were measured by the electrochemical workstation and mechanical testing equipment (MTS). The results show that the corrosion resistance and wear resistance of the Al 2 O 3 -coated MWCNTs/epoxy composite coating have some improvement compared with MWCNTs/epoxy, but a reduction in the flexibility of the Al 2 O 3 -coated MWCNTs/epoxy (2 wt%) composite coating.

Preparation of graphene oxide modified by titanium dioxide to enhance the anti-corrosion performance of epoxy coatings

“…7(c) indicates that the impedance of coating conformed to the organic coating at the initial soaking, and the data in Fig. 7(e) is consistent with the model at the mid-soaking soaking [22,[30][31][32]. Thus, the transition time was 16 h for pure epoxy, and 42, 66, and 90 h for 2wt.% GO/epoxy, 2wt.% nano-TiO 2 /epoxy, and 2wt.% TiO 2 -GO/epoxy, respectively.…”

“…Besides, redundant emulsion was carefully poured into a homemade container, respectively. Finally, The epoxy-coated steels and cured epoxy coatings were attained using two steps: steels and containers were baking in an oven at 120 °C for 1 h followed by 220 °C for other 1.5 h [22]. The dry film thickness of coatings was required to be measured utilizing screw micrometer and calibrator.…”

“…However, epoxy resins are inherently shortcoming, fabricating the high temperature curing epoxy solvent-borne coatings, which makes them inevitably produced plentiful micro-pore via solvent evaporation [20,22]. The corrosive liquid medium can quickly permeate the coating into the protected substrate using micro-pores generating poor corrosion resistance.…”

Fabrication of graphene oxide–alumina hybrids to reinforce the anti-corrosion performance of composite epoxy coatings

“…Then, the seriflux mixture was sprayed on the surface of the steel after ultrasonic oscillation and mechanical stirring, degassed in a vacuum oven at room temperature for 0.5 h, and cured with the following cycle: 120 for 1 h and 220 for 2 h [33]. The pure epoxy sample was also prepared under the same curing condition.…”

“…(a) and 8(b) displayed the impedance spectra of the composite coatings (2wt.% GO/epoxy, 2wt.% Al 2 O 3 /epoxy, and 2wt.% GO-Al 2 O 3 /epoxy) and the pure epoxy after 108 h, 142 h, 240 h and 60 h of immersion, respectively, which indicated that the impedance of coating conformed to the organic coating at the last corrosion state[33,[45][46][47]. The results verified that the GO-Al 2 O 3 nanocomposites exhibited the higher anti-corrosion performance of epoxy coatings than Al 2 O 3 and GO, which owed to well dispersion and the excellent inherent plugging micro-pores performance.…”