scholarly journals Corrosion Protection Evaluation of Mild Steel: The Role of Hybrid Materials Loaded with Inhibitors

2020 ◽  
Vol 10 (18) ◽  
pp. 6594 ◽  
Author(s):  
Ioannis A. Kartsonakis ◽  
Costas A. Charitidis
Keyword(s):  
Composite Materials ◽  
Mild Steel ◽  
Hybrid Materials ◽  
Sol Gel ◽  
Titanium Oxides ◽  
Stimuli Responsive ◽  
Corrosion Mechanisms ◽  
New Compounds ◽  
Structural Aspects

In the present work, an assessment of the corrosion behavior of mild steel in the presence of an organic corrosion inhibitor loaded into hybrid composite materials is performed. Hybrid organic–inorganic nanocontainers based on cerium and titanium oxides were fabricated via a combination of radical polymerization together with the coprecipitation method and sol-gel technique. The corrosion inhibition role of these hybrid materials loaded with an inhibitor is considered. A set of characterization assays addressing morphology, composition and structural aspects of the exposed steels is illustrated, along with electrochemical evaluations. The results reveal enhanced stimuli responsive anticorrosion ability of the produced hybrid materials. Furthermore, upon corrosion, new compounds are formed onto the exposed areas of the treated metals. The conducted experiments shed light on the corrosion mechanisms for steel alloys as well as the actuation of the fabricated composite materials, paving the way for future developments in this area.

scholarly journals TiO2–Polymer Nano–Composites by Sol–Gel

1995 ◽  
Vol 18 (1) ◽  
pp. 31-37 ◽  
Author(s):  
A. C. Pierre ◽  
G. Campet ◽  
S. D. Han ◽  
S. Y. Huang ◽  
E. Duguet ◽  
...  
Keyword(s):  
Composite Materials ◽  
Hybrid Materials ◽  
Polyethylene Oxide ◽  
Sol Gel ◽  
Processing Parameters ◽  
Nano Composites ◽  
Electrochemical Cells ◽  
Primary Evaluation

Sol-gel processes make it possible to develop new hybrid electrolyte materials of the type ceramic-polymer, known as Nano-Crystallite-Insertion-Material (NCIM). They can be used in reversible alkali electrochemical cells after insertion with cations such as Li+. In the present study, TiO2-polyethylene oxide hybrid materials were synthesized from TiCl4and from Ti ethoxide. Their structure is analyzed in relation with the processing parameters. A primary evaluation of the nanoscale composite materials for reversible Li insertion was performed.

UV Curable Organic-Inorganic Hybrid Materials

2000 ◽  
Vol 628 ◽  
Author(s):  
Guang-Way Jang ◽  
Ren-Jye Wu ◽  
Yuung-Ching Sheen ◽  
Ya-Hui Lin ◽  
Chi-Jung Chang
Keyword(s):  
Hybrid Materials ◽  
Colloidal Silica ◽  
Sol Gel ◽  
Solution Ph ◽  
Uv Curable ◽  
Inorganic Hybrid ◽  
Degradation Temperature ◽  
Sol Gel Process ◽  
The Stability ◽  
Thermal Degradation Temperature

This work successfully prepared an UV curable organic-inorganic hybrid material consisting of organic modified colloidal silica. Applications of UV curable organic-inorganic hybrid materials include abrasion resistant coatings, photo-patternable thin films and waveguides. Colloidal silica containing reactive functional groups were also prepared by reacting organic silane and tetraethyl orthosilicate (TEOS) using sol-gel process. In addition, the efficiency of grafting organic moiety onto silica nanoparticles was investigated by applying TGA and FTIR techniques. Experimental results indicated a strong interdependence between surface modification efficiency and solution pH. Acrylate-SiO2 hybrid formation could result in a shifting of thermal degradation temperature of organic component from about 200°C to near 400°C. In addition, the stability of organic modified colloidal silica in UV curable formula and the physical properties of resulting coatings were discussed. Furthermore, the morphology of organic modified colloidal silica was investigated by performing TEM and SEM studies‥

The Non-Causal Character of Renormalization Group Explanations

2018 ◽  
Author(s):  
Margaret Morrison
Keyword(s):  
Probability Theory ◽  
Renormalization Group ◽  
Dynamical Systems ◽  
Recent Literature ◽  
Mathematical Explanation ◽  
Causal Status ◽  
Physical Information ◽  
The Relationship ◽  
Structural Aspects

After reviewing some of the recent literature on non-causal and mathematical explanation, this chapter develops an argument as to why renormalization group (RG) methods should be seen as providing non-causal, yet physical, information about certain kinds of systems/phenomena. The argument centres on the structural character of RG explanations and the relationship between RG and probability theory. These features are crucial for the claim that the non-causal status of RG explanations involves something different from simply ignoring or “averaging over” microphysical details—the kind of explanations common to statistical mechanics. The chapter concludes with a discussion of the role of RG in treating dynamical systems and how that role exemplifies the structural aspects of RG explanations which in turn exemplifies the non-causal features.

Sticky ends in a self-assembling ABA triblock copolymer: the role of ureas in stimuli-responsive hydrogels

2019 ◽  
Vol 4 (1) ◽  
pp. 91-102 ◽  
Author(s):  
Ryan T. Shafranek ◽  
Joel D. Leger ◽  
Song Zhang ◽  
Munira Khalil ◽  
Xiaodan Gu ◽  
...  
Keyword(s):  
Self Assembly ◽  
Viscoelastic Properties ◽  
Triblock Copolymer ◽  
Thermal Response ◽  
Stimuli Responsive ◽  
Self Assembling ◽  
Polymeric Hydrogels ◽  
Aba Triblock Copolymer ◽  
Responsive Hydrogels

Directed self-assembly in polymeric hydrogels allows tunability of thermal response and viscoelastic properties.

Autonom autobiografisch: Zu Thomas Manns Die Entstehung des Doktor Faustus

2020 ◽  
Vol 55 (1) ◽  
pp. 83-99
Author(s):  
Lukas Hermann
Keyword(s):  
Thomas Mann ◽  
Autobiographical Writing ◽  
Documentary Source ◽  
Textual Evidence ◽  
Structural Frame ◽  
The Status ◽  
Structural Aspects

AbstractIn its peritext, Thomas Mann’s Entstehung des Doktor Faustus is described as a “Roman eines Romans”. The essay reasons that this description of its genre as well as structural aspects of its composition mark it as an autobiographical text. Instead of following most studies on the Doktor Faustus, which regard the Entstehung simply as a documentary source for exposing autobiographical intricacies of Mann’s novel, textual evidence for the Entstehung’s autonomy is given. The analysis focuses first on the structural frame of the Entstehung in order to show Mann’s central techniques of autobiographical self-stylization. In this context auto-fictional elements can also be identified. Exemplary passages from two longer sections are taken into account based on these findings. While the Doktor Faustus is a recurrent topic in these passages, it is not, by any means, the only one. Combined with varying autobiographical writing techniques, the Entstehung is thus displaying continuous independence from the Faustus. Based on these insights, future Mann studies on both works may reevaluate the role of the Entstehung for the reception of the Faustus and the status of autobiographical literature in the works of Thomas Mann.

The Influence of Polymer on Fe(II)Citrate Release from Hybrid Materials Synthesized via Sol–Gel

2020 ◽  
Vol 389 (1) ◽  
pp. 1900057
Author(s):  
Michelina Catauro ◽  
Elisabetta Tranquillo ◽  
Giovanni Dal Poggetto ◽  
Daniele Naviglio ◽  
Federico Barrino
Keyword(s):  
Hybrid Materials ◽  
Sol Gel ◽  
Citrate Release

scholarly journals Synthesis, Structural, Morphological and Thermal Characterization of Five Different Silica-Polyethylene Glycol-Chlorogenic Acid Hybrid Materials

Polymers ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 1586
Author(s):  
Michelina Catauro ◽  
Pavel Šiler ◽  
Jiří Másilko ◽  
Roberta Risoluti ◽  
Stefano Vecchio Ciprioti
Keyword(s):  
Polyethylene Glycol ◽  
Chlorogenic Acid ◽  
Hybrid Materials ◽  
Sol Gel ◽  
Antibacterial Properties ◽  
Silica Matrix ◽  
Sem Images ◽  
Fixed Amount ◽  
Organic Components ◽  
Free Material

The present study investigated the structure, morphology, thermal behavior, and bacterial growth analysis of novel three-component hybrid materials synthesized by the sol-gel method. The inorganic silica matrix was weakly bonded to the network of two organic components: a well-known polymer such as polyethylene glycol (PEG, average molar mass of about 4000 g/mol), and an antioxidant constituted by chlorogenic acid (CGA). In particular, a first series was made by a 50 wt% PEG-based (CGA-free) silica hybrid along with two 50 wt% PEG-based hybrids containing 10 and 20 wt% of CGA (denoted as SP50, SP50C10 and SP50C20, respectively). A second series contained a fixed amount of CGA (20 wt%) in silica-based hybrids: one was the PEG-free material (SC20) and the other two contained 12 and 50 wt% of PEG, respectively (SP12C20 and SP50C20, respectively), being the latter already included in the first series. The X-ray diffraction (XRD) patterns and scanning electron microscope (SEM) images of freshly prepared materials confirmed that all the materials were amorphous and homogeneous regardless of the content of PEG or CGA. The thermogravimetric (TG) analysis revealed a higher water content was adsorbed into the two component hybrids (SP50 and SC20) because of the availability of a larger number of H-bonds to be formed with water with respect to those of silica/PEG/CGA (SPC), where silica matrix was involved in these bonds with both organic components. Conversely, the PEG-rich materials (SP50C10 and SP50C20, both with 50 wt% of the polymer) retained a lower content of water. Decomposition of PEG and CGA occurred in almost the same temperature interval regardless of the content of each organic component. The antibacterial properties of the SiO2/PEG/CGA hybrid materials were studied in pellets using either Escherichia coli and Enterococcus faecalis, respectively. Excellent antibacterial activity was found against both bacteria regardless of the amount of polymer in the hybrids.

The preparation of poly(methylsilsesquioxane) network-polyimide hybrid materials by the sol-gel process and their properties

1994 ◽  
Vol 6 (1) ◽  
pp. 43-52 ◽  
Author(s):  
Yoshitake Iyoku ◽  
Masa-aki Kakimoto ◽  
Yoshio Imai
Keyword(s):  
Hybrid Materials ◽  
Sol Gel ◽  
Tensile Modulus ◽  
Hybrid Films ◽  
Elongation At Break ◽  
Dimethyl Acetamide ◽  
Flexible Films ◽  
Sol Gel Process ◽  
Heating Up ◽  
Silicone Content

Poly(methylsilsesquixoane) network (silicone)-polyimide hybrid materials were successfully prepared by the sol-gel reaction of methyltriethoxysilane (MTES). The ethoxysilyl group in MTES was hydrolyzed and polycondensed in the solution of the polyamic acid, derived from pyromellitic dianhydride and bis(4-aminophenyl)ether, in N,N-dimethyl-acetamide (DMAc). The hybrid films were obtained by casting the reaction mixture, followed by heating up to 300°C. The hybrid materials containing 0-60wt% of silicone afforded flexible films. The films containing less than 7 wt% silicone were yellow and transparent, whereas the films with higher silicone content were yellow and opaque. Silicone particles with a diameter of around 1-10 μm were observed in the fracture surface of the hybrid films by scanning electron microscopy. Although the tensile strength and tensile modulus of the films obtained decreased with increasing silicone content. the value of the elongation at break remained at 60% up to 30% silicone content.

scholarly journals Mechanisms of passivation and chloride-induced corrosion of mild steel in sulfide-containing alkaline solutions

2021 ◽  
Author(s):  
Shishir Mundra ◽  
John L. Provis
Keyword(s):  
Mild Steel ◽  
Surface Film ◽  
Critical Role ◽  
Chloride Concentration ◽  
Alkaline Solutions ◽  
Sulfide Concentration ◽  
Chloride Induced Corrosion ◽  
Alkaline Sulfide ◽  
High Sulfide

AbstractThe pore fluid within many concretes is highly alkaline and rich in reduced sulfur species, but the influence of such alkaline-sulfide solutions on the surface film formed on steel reinforcement is poorly understood. This study investigates the critical role of HS− in defining mild steel passivation chemistry. The surface film formed on the steel in alkaline-sulfide solutions contains Fe(OH)2 and Fe–S complexes, and the critical chloride concentration to induce corrosion increases at high sulfide concentration. However, this behavior is dependent on the duration of exposure of the steel to the electrolyte, and the nature of the sulfidic surface layer.

Sign in / Sign up

Export Citation Format

Share Document