Graphene-Based Reinforcing Filler for Double-Layer Acrylic Coatings

Abstract

This study aims to demonstrate the remarkable features of graphene-based fillers, which are able to improve the protective performance of acrylic coatings. Furthermore, the joint application of a cataphoretic primer and a spray top coat, containing graphene and functionalized graphene oxide flakes, respectively, enables the deposition of a double-layer coating with high conductivity and abrasion resistance properties, capable of offering excellent corrosion resistance to the metal substrate. The surface morphology of the single- and double-layer coatings was investigated by optical and electron microscopies, analysing the defectiveness introduced in the polymer matrix due to the filler agglomeration. The behavior in aggressive environments was assessed by exposure of the samples in the salt spray chamber, evaluating the blister formation and the adhesion level of the coatings. Electrochemical impedance spectroscopy measurements were employed to study the corrosion protection properties of the coatings, whose conductivity and abrasion resistance features were analysed by conductivity assessment and scrub tests, respectively. The incorporation of graphene-based fillers in the cataphoretic primer improves the corrosion protection properties of the system, while the graphene flakes provide the top coat spray layer with high conductivity and excellent abrasion resistance features. Thus, this work demonstrates the possibility of employing different types of graphene-based fillers and deposition methods for the creation of multifunctional coatings.

Esthetic performance of thermochromic pigments in cataphoretic and sprayed coatings for outdoor applications

“…The thickness of the cataphoretic primer (both in samples C and CS) is equal to about 30 μm, in agreement with the results usually achieved with this deposition technique 25,26 . The thickness of the sprayed layers is also constant, equal to about 80 μm in the pigmented primer and 70 μm in the clear topcoat.…”

“…A 300 x 50 mm 2 flat stainless steel plate, used as anode, was placed at a distance of 800 mm from the sample. The electrodeposition time and the applied voltage value were kept equal to 120 s and 75 V, respectively, as the process parameters were optimized in previous works 25–27 . The cataphoretic thermochromic coating was labeled as “C.”…”

“…Many studies in literature regard the deposition of cataphoretic coatings on many different substrates, such as aluminum alloys 15–20 and Zn–Mn alloys, 21 with the application of different pretreatments 22 . Finally, reinforcing filler based on ceria‐titania nanoparticles 23 and functionalized graphene oxide flakes 24–27 have been added to cataphoretic baths to improve the protective properties of the polymeric matrix.…”

Facile Route to Effective Antimicrobial Aluminum Oxide Layer Realized by Co-Deposition with Silver Nitrate

“…The scrub test is a technique developed for the study of abrasion resistance of organic coatings, assessing the reinforcing contribution of pigments [70][71][72] and inorganic [73] and organic [74][75][76] fillers. The alumina layer possesses much greater abrasion resistance than a typical organic coating: as a matter of fact, in this work, the scrub test was chosen not to replicate particularly abrasive phenomena, but to simulate repeatedly cleaning the surface.…”

Impact of High Concentrations of Cellulose Fibers on the Morphology, Durability and Protective Properties of Wood Paint

“…Figure 2 shows the SEM micrograph of both the top view (on the left) and the cross section (on the right) of the four kinds of coatings. Figure 2a, relative to the reference sample F0, free of filler, exhibits a compact and defect-free layer, typical of the layers deposited with the spray technique [63], with thickness of about 140 µm. On the other hand, the introduction of cellulose fibers into sample F5 (Figure 2b) leads to a considerable increase in layer thickness, which reaches 250 µm.…”