Influence of Rust Inhibitor on the Corrosion Resistance of Reinforcement in Cement Paste with Chloride

The electrical resistance and polarization effect of cement paste containing reinforcement were tested to research the anti-corrosion properties of steel bars in cement paste. Moreover, the microstructure and composition of passivation film and rust on the steel bars were studied. The water–cement ratio of the cement paste in this study was 0.3, with 0.5% NaCl, 1% NaNO2, and 1% Benzotriazole, and an assembly unit of 0.5% NaNO2 + 0.5% Benzotriazole by mass of cement was added to the cement to provide a chloride environment. X-ray photoelectron spectroscopy (XPS) and scanning electron microscope (SEM) were applied to research the composition of the passivation film and the microstructure of the cement paste, respectively. The results indicated that the samples with the assembly unit of 0.5% NaNO2 + 0.5% Benzotriazole showed the highest electrical resistance and polarization electrical resistance, while the specimens with 1.0% Benzotriazole showed the lowest electrical resistance and polarization electrical resistance. Moreover, the passivation film of steel bars weakened with increasing distance from the surface of the steel bars. Therefore, the corrosion of steel bars becomes more serious with increasing distance. Finally, the influence of the rust inhibitor on the corrosion resistance of steel bars in the specimens decreased in the following order: 0.5% NaNO2 + 0.5% Benzotriazole >1.0% NaNO2>1.0% Benzotriazole.

Oil absorbency of diatomite-embedded polypropylene meltblown composite structures

In this study, optimized conditions were established for diatomite grinding, which is a natural inorganic mineral with inherently high oil absorption capacity. Diatomite surface was modified with a fluorocarbon chemical and stearic acid via facile methods for enhancing compatibility between polypropylene and diatomite. Polypropylene/diatomite composites were generated in a twin screw extruder with/without using compatibilizer, and nonwoven structures were produced via meltblown technique. Pore size and void content analyses showed that addition of diatomite led to thicker fibers (1–17 µm (the neat polypropylene) vs. 1–32 µm (2 wt.% diatomite containing polypropylene)). Diatomite incorporation into polypropylene resulted in a rigid and brittle structure and a worsened oil absorption property (rust inhibitor oil absorption capacity: 1184% ± 105% (the neat polypropylene) vs. 718% ± 78% and 1089% ± 136% (2 wt.% diatomite containing polypropylene)). Increasing oil viscosity resulted in increased discrepancy among the oil absorption capacities of the neat polypropylene and diatomite containing polypropylene. Analysis of variance tests showed no changes or statistically insignificant differences in oil absorbency.

Research and Development Display Agent Determination of Nitrite Content in Concrete

The invention relates to building materials field, especially the determination method relates to a concrete root ion content of nitrite. Nitrite as antifreeze in the concrete, early strength agent and rust resistance agent composition is widely used in reinforced concrete structure, the admixture of cement quality generally accounted for 1-3% range, its content is too little and too much will affect the durability and workability of concrete, if insufficient dosage when the early strength, anti-freezing and anti-rust effect is not obvious，otherwise affect the workability and durability，when used as a rust inhibitor and dispersant, insufficient dosage, sometimes, can produce local corrosion and accelerate the macro cell corrosion.Therefore, the determination of nitrite ion content in root of concrete (or mortar) has become the inevitable trend of modern concrete production.

Study on the Anti-Rust Mechanism of Compound Rust Inhibitor TW742

The anti-rust mechanism of TW742 is mainly studied in this paper. TW742 was dissolved in kinds of base oils to make anti-rust oils, and the effect of these oils were tested through some experiments, which indicated that both the humid heat test and the salt water immersion were good. So it is concluded the protective film of TW742 on the metal is mainly Physical adsorption film, which can keep H2O、O2、Cl-、from the metal.