pH-responsive nanovalves based on hollow mesoporous silica spheres for controlled release of corrosion inhibitor

Abstract

In the present study, a new encapsulation technique for corrosion inhibitor is proposed. The hollow mesoporous silica spheres (HMSs) were synthesized by the co-templates method as nanocontainers for corrosion inhibitor, benzotriazole (BTA) and the supramolecular nanovalves, consisting of cucurbit[6]uril (CB[6]) rings and the functional stalks attached to the surface of HMSs achieved on-demand release. The synthesis process of HMSs and the assembly process of the nanovalves were confirmed by SEM, TEM, N(2) adsorption/desorption, FTIR, TGA and solid-state (13)C CP/MAS NMR. The encapsulation capacity and release characteristics of BTA-loaded, assembled HMSs were investigated. The HMSs assembled with the nanovalves possessed a higher encapsulation capacity for BTA than MCM-41 assembled under the same procedure due to its huge hollow internal structure. The pH-controlled release properties of BTA from the assembled HMSs under different pH environments were monitored by ultraviolet absorption spectra. The release profiles showed that there was almost no leakage of BTA from the assembled HMSs in neutral solution, while in alkaline solution BTA released very quickly, and the release rate increased with increasing pH values. Such a property makes the HMSs assembled with the pH-responsive nanovalves have great potential applications in smart anticorrosion coatings.

Polypyrrole nanowire/TiO 2 nanotube nanocomposites as photoanodes for photocathodic protection of Ti substrate and 304 stainless steel under visible light

“…Some of the most common methods employed to achieve corrosion resistance are anticorrosion coatings [2][3][4], corrosion inhibitors [5,6], nanocomposites [7,8], and electrochemical protection [9][10][11][12]. Traditional electrochemical protection methods mainly include impressed current [9,11] and sacrificial anode cathodic protection systems [10,12].…”

A Comparative Study Between Spray-Drying and Fluidized Bed Coating Processes for the Preparation of Pramipexole Controlled-Release Microparticles for Orally Disintegrating Tablets

“…However, investigation of these considerations has rarely been reported, with the exception of compression of coated microparticles (or pellets). [13] There have been several research studies on the preparation of controlled-release microparticles, [14,15] and a few preparation processes have been accepted in commercial industries. [16,17] Thus, in the present study, two specific preparation processes, spray drying and fluidized bed coating, were chosen to prepare controlled-release microparticles for ODT because they are pharmaceutically accepted processes and are proper for scale-up and good manufacturing process.…”

Dual-action smart coatings with a self-healing superhydrophobic surface and anti-corrosion properties

“…To this end, a major class of self-healing coatings were developed via the incorporation of corrosion inhibitors such as benzotriazole (BTA) [32][33][34] , 8-hydroxyquinoline (8HQ) 35 and cerium-based inhibitors 36,37 . When damage occurs, the corrosion inhibitors leach out and form barrier films by chemical complexation or physical adsorption on the exposed substrates [38][39][40] .…”