Effects of Surface Pretreatment of Titanium Substrates on Properties of Electrophoretically Deposited Biopolymer Chitosan/Eudragit E 100 Coatings

Abstract

The preparation of the metal surface before coating application is fundamental in determining the properties of the coatings, particularly the roughness, adhesion, and corrosion resistance. In this work, chitosan/Eudragit E 100 (chit/EE100) were fabricated by electrophoretic deposition (EPD) and both their microstructure and properties were investigated. The present research is aimed at characterizing the effects of the surface pretreatment of titanium substrate, applied deposition voltage, and time on physical, mechanical, and electrochemical properties of coatings. The coating’s microstructure, topography, thickness, wettability, adhesion, and corrosion behavior were examined. The applied process parameters influenced the morphology of the coatings, which affected their properties. Coatings with the best properties, i.e., uniformity, proper thickness and roughness, hydrophilicity, highest adhesion to the substrate, and corrosion resistance, were obtained after deposition of chit/EE100 coating on nanotubular oxide layers produced by previous electrochemical oxidation.

Influence of Surface Modification of Titanium and Its Alloys for Medical Implants on Their Corrosion Behavior

“…The distance between the electrodes was set at 10 mm. In Procedure A, according to previous studies [ 15 ], the anodization voltage and time were adjusted to 20 V and 20 min, respectively. After oxidation, the samples were washed thoroughly with distilled water.…”

“…There have been some papers in the last few years describing corrosion parameters of different coatings deposited or layers created on titanium [ 1 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 ] and its alloys: Ti6Al4V [ 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 ], Ti13Nb13Zr [ 14 , 24 , 25 , 26 , 27 ]. The coatings were designed and produced particularly to enhance corrosion resistance [ 1 , 4 , 6 , 7 , 8 , 9 , 11 , 16 , 17 , 18 , 19 , 21 , 22 , 23 , 24 ] or the corrosion characteristics were determined only to verify whether and to what extent the applied coating may affect the degradation process [ 5 , 10 , 12 , 13 , 14 , 15 , 20 , 25 ]. The main difference between coated materials was the presence or the absence of an artificial titanium oxide layer created by oxidation in different conditions [ …”

“…The coatings were designed and produced particularly to enhance corrosion resistance [ 1 , 4 , 6 , 7 , 8 , 9 , 11 , 16 , 17 , 18 , 19 , 21 , 22 , 23 , 24 ] or the corrosion characteristics were determined only to verify whether and to what extent the applied coating may affect the degradation process [ 5 , 10 , 12 , 13 , 14 , 15 , 20 , 25 ]. The main difference between coated materials was the presence or the absence of an artificial titanium oxide layer created by oxidation in different conditions [ 1 , 3 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 15 , 19 , 20 ] such as direct voltage anodic oxidation, micro-arc oxidation (MAO), or hydrothermal oxidation. The coatings other than rutile/anatase were composed of some metals [ 12 ], polymers [ 4 , 5 , 11 , 13 , 14 , 15 , 16 ], organic compounds [ 25 ], ceramics [ 5 , 9 , 10 , 23 , 24 …”

“…The main difference between coated materials was the presence or the absence of an artificial titanium oxide layer created by oxidation in different conditions [ 1 , 3 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 15 , 19 , 20 ] such as direct voltage anodic oxidation, micro-arc oxidation (MAO), or hydrothermal oxidation. The coatings other than rutile/anatase were composed of some metals [ 12 ], polymers [ 4 , 5 , 11 , 13 , 14 , 15 , 16 ], organic compounds [ 25 ], ceramics [ 5 , 9 , 10 , 23 , 24 , 25 , 26 , 27 ], oxides [ 5 , 6 , 8 , 9 , 12 , 19 , 22 , 24 , 25 ], graphene and carbides [ 1 , 18 , 20 ], and bioglass [ 17 ]. It is to underline that the most effective way to increase the corrosion resistance of titanium surfaces is to create a smooth and nonpermeable oxide layer.…”

The nitriding effect on the stability and mechanical properties of the iron titan phase: first-principles investigation

“…For instance, it has been shown that a pre-treatment of a substrate surface has a positive effect on the morphology and properties of electrophoretically deposited biopolymer coatings. 7,8 Experimental studies on material surface coatings show that, for example, the contact welding method improves the properties of coatings and further makes it possible to modify them, while ion nitriding in a glow charge with deposition of protective coatings increases adhesion properties and corrosion resistance. 9,10 However, finding conditions to achieve optimal mechanical characteristics of a coating requires a great amount of efforts both from technological and fundamental aspects for studying the features of structure and property formation.…”