Sonochemical Synthesis of ZnO Encapsulated Functional Nanolatex and its Anticorrosive Performance

Sonochemical approach for synthesis of zinc oxide-poly methyl methacrylate hybrid nanoparticles and its application in corrosion inhibition

Hybrid nanoparticles (HNPs) with zinc oxide and polymethyl metha acrylate (inorganic/ polymer) were synthesized through the exploitation of ultrasound approach. The synthesized HNPs were further characterized employing transmission electron microscopy and x-ray diffraction. ZnO-PMMA based HNPs exhibit excellent protection properties to mild steel from corrosion when gets exposed to acidic condition. Electrochemical impendence spectroscopy (EIS) analysis was accomplished to evaluate the corrosion inhibition performance of MS panel coated with 2 wt% or 4 wt% of HNPs and its comparison with bare panel and that of loaded with only standard epoxy coating., Tafel plot and Nyquist plot analysis depicted that the corrosion current density (I_corr) decreases from 16.7 A/m² for bare material to 0.103 A/m² for 4% coating of HNPs. Applied potential (E_corr) values shifted from negative to positive side. These results were further supported by qualitative analysis. The images taken over a period of time indicated the increase in lifetime of MS panel from 2 to 3 days for bare panel to 10 days for HNPs coated panel, showing that ZnO-PMMA HNPs have potential application in metal protection from corrosion by forming a passive layer.

A Review on Sonochemistry and Its Environmental Applications

Sonochemistry is a significant contributor to green science as it includes: (i) the use of less toxic compounds and environmentally safe solvents, (ii) improvement of reaction conditions and selectivity, (iii) no toxic sludge generation, (iv) reduction in the energy use for chemical transformations, (v) reusability of materials. In water and wastewater treatment, ultrasound is used as an advanced oxidation process to eliminate refractory pollutants. Ultrasound is also used as a very effective sludge pretreatment technology in wastewater treatment plants to facilitate biogas production. Moreover, sonochemical synthesis of nanoparticles has recently attracted great attention as a greener protocol. This paper presents the main applications of ultrasound in environmental remediation and protection. The study also introduces mechanism for the degradation of pollutants from water via sonication in aqueous media and the principle factors affecting the cavitational effect.

Ultrasonic encapsulation - A review

Encapsulation of materials in particles dispersed in water has many applications in nutritional foods, imaging, energy production and therapeutic/diagnostic medicine. Ultrasonic technology has been proven effective at creating encapsulating particles and droplets with specific physical and functional properties. Examples include highly stable emulsions, functional polymeric particles with environmental sensitivity, and microspheres for encapsulating drugs for targeted delivery. This article provides an overview of the primary mechanisms arising from ultrasonics responsible for the formation of these materials, highlighting examples that show promise particularly in the development of foods and bioproducts.

Ultra low water adhesive metal surface for enhanced corrosion protection

A superhydrophobic surface with ultra low water adhesive force is fabricated on various metals for enhanced corrosion protection.

Ultrasound assisted synthesis of PANI/ZnMoO4 nanocomposite for simultaneous improvement in anticorrosion, physico-chemical properties and its application in gas sensing

Ultrasound assisted in-situ semi-batch emulsion polymerization has been used for the preparation of polyaniline (PANI) and PANI/ZnMoO4 nanocomposite with different loading of ZnMoO4 (ZM) nanoparticles. ZM nanoparticles were functionalized using Myristic acid (MA) for better compatibility with PANI. The cavitational effects induced due to ultrasonic irradiations have been shown significant enhancement in the dispersion of functionalized ZM nanoparticles into the PANI during ultrasound assisted in-situ emulsion polymerization process. TEM images of PANI/ZM nanocomposite particles give the direct evidence of fine dispersion and encapsulation of MA treated ZM nanoparticles in PANI matrix. The presence of ZM nanoparticles in PANI/ZM nanocomposite shows significant improvement in the mechanical (cross-cut adhesion), thermal, anticorrosion and sensing properties of PANI/ZM nanocomposite/alkyd coatings over PANI/alkyd and neat alkyd resin coating. Fine and uniform dispersion of ZM nanoparticles in PANI matrix using this novel synthesis method (PANI (p-type)/ZM (n-type) hetero-junction) improves LPG sensing ability and minimizes response time to sense LPG significantly compared with neat PANI.

Linseed oil polyol/ZnO bionanocomposite towards mechanically robust, thermally stable, hydrophobic coatings: a novel synergistic approach utilising a sustainable resource

Linseed polyol/ZnO bionanocomposite produced strong, well-adherent, flexibility-retentive, thermally stable, hydrophobic, “green” corrosion protective coatings via an in situ solventless “green” approach.

Enhanced corrosion inhibitive effect of p-methoxybenzylidene-4,4′-dimorpholine assembled on nickel oxide nanoparticles for mild steel in acid medium

The corrosion inhibition efficiency of p-methoxybenzylidene-4,4′-dimorpholine (p-MBDM) and p-MBDM assembled on nickel oxide nanoparticles (NiONPs) was investigated here.

Physico-mechanical and electrochemical corrosion behavior of soy alkyd/Fe3O4 nanocomposite coatings

Anticorrosive nanocomposite coatings were synthesized using soya alkyd a renewable polymer matrix and Fe₃O₄ nanoparticles as filler.

Synthesis of high solids content low surfactant/polymer ratio nanolatexes

A new two-stage strategy for the synthesis of high-solids-content low-surfactant/polymer ratio nanolatexes was developed. In the first stage, the knowledge-based strategy is used to obtain 18 wt % nanolatexes with the maximum number of particles and using a fraction of the surfactant. In the second stage, the rest of the surfactant is employed to stabilize these particles while they are growing to reach the target solids content. The final particle size results from the interplay between limited particle coagulation and secondary homogeneous nucleation during the second stage. Smaller particle sizes were obtained for surfactants able to desorb from the existing particles and diffuse quickly to the newly formed particles. Waterborne nanoparticles as small as 32 nm in diameter were obtained with 36 wt % solids content and solids content/(surfactant/polymer) ratio higher than 26. This represents a substantial improvement with respect to the best results reported in the literature (dp = 32 nm; 23 wt % solids, and solids content/(surfactant/polymer) = 21).