Nanofiber Composite Coating with Self-Healing and Active Anticorrosive Performances

Abstract

Synergetic self-healing anticorrosion behaviors, by forming a self-assembly protective layer and repairing coating passive barrier, exhibit great potential in handling the notorious metal corrosion phenomenon. Herein, we developed a nanofiber-supported anticorrosion coating with synergistic protection effects of both self-healing and active corrosion inhibition, via a facile electrospinning combined coating technique. Polycaprolactone (PCL) nanofiber integrated with 2-mecapobenzothiazole-loaded halloysite nanotubes (HNTs-MBT) is directly deposited on the surface of metal substrate, forming an interconnected fiber network framework. The encapsulated corrosion inhibitor MBT can be released by a pH-triggered manner to realize instant corrosion protections. Additionally, coating defects could be repeatedly repaired by continuous polymer fiber upon heat treatment and the anticorrosion efficiency effectively remained, even after three cycles of damage–healing. Moreover, the repaired coating also exhibited durable anticorrosion performance, mainly attributed to the synergetic effects of both thermal-triggered bulk healing and active corrosion inhibition. This type of dual-functional coating provides efficient anticorrosive performances and may show great promise in long-term corrosion protection.

Anticorrosion Coating with Heterogeneous Assembly of Nanofillers Modulated by a Magnetic Field

“…First, Nyquist plots with a frequency of 10 5 –10 –2 Hz were utilized to evaluate the anticorrosion ability of the coatings (Figure c). Generally, a larger diameter of semicircle arc is associated with a higher R ct (charge transfer resistance), which indicates a greater resistance of corrosive media diffusion to metal. , The semicircle diameters of Nyquist plots were extended with the increase in NPs content until the doping amount reached 0.7% as excess particle aggregation may accelerate the deterioration of coatings by introducing additional corrosive species diffusion routes . The NP 0.7 /EP sample always remained the largest diameter, implying the strongest active anticorrosion efficiency compared to the other doping dosages.…”

“…19,57 The semicircle diameters of Nyquist plots were extended with the increase in NPs content until the doping amount reached 0.7% as excess particle aggregation may accelerate the deterioration of coatings by introducing additional corrosive species diffusion routes. 28 The NP 0.7 /EP sample always remained the largest diameter, implying the strongest active anticorrosion efficiency compared to the other doping dosages. However, the sample NP 0.7 /EP-R without magnetic field modulation has a much smaller semicircle in its Nyquist plot than NP 0.3 /EP and NP 0.7 /EP, which exhibit a weak corrosion inhibition effect.…”

Self‐Healing Fibrous Membranes

“…First, no matter whether the healing process of extrinsic self‐healing materials is controlled by external stimulation or not, due to the consumption of the encapsulated agents with the increase of healing cycles, there will always be a moment when the healing agents will be exhausted. Thus, the number of healing cycles of core–shell structured extrinsic SFMs is limited [14, 33b] . This problem is common to all microcapsule‐based extrinsic self‐healing materials, which rely on healing agents.…”

“…Most intrinsic SFMs based on molecular chain interdiffusion use thermoplastic polymers as raw materials, for example polycaprolactone (PCL), [33b] where nanoparticles exhibiting a photothermal effect are introduced at the inner or outer areas of the fiber through doping or surface recombination as “nano heaters” (Figure 5a) [64] . The nanoparticles most widely used for this purpose are Au or graphene, and metal–organic frameworks [65] .…”

Self-Healing, Solvent-Free, Anti-Corrosion Coating Based on Skin-like Polyurethane/Carbon Nanotubes Composites with Real-Time Damage Monitoring

“…Under certain circumstances, this forms a barrier film over an exposed substrate, protecting it from the corrosive media. Fu et al [ 8 ] compounded polycaprolactone (PCL) nanofibers with 2-mercaptobenzothiazole-loaded halloysite nanotubes (HNTs-MBT) and deposited them on the surface of a metal substrate to form an interconnected fiber network. The encapsulated MBTs could be released by pH-triggering and repair scratches in a thermal-initiated manner, showing a great potential for corrosion protection applications.…”