Curing mechanism,heat resistance,and anticorrosion properties of a furan/methyl phenyl silicone coating

A coating composed by methyl phenyl silicone resin (PSi) and furan resin (FR) was prepared, and its curing mechanism, heat resistance, and anticorrosion properties were investigated by Fourier transform infrared spectroscopy, thermogravimetric analysis, electrochemical test, and chemical resistance test. Aldol condensation reaction between FR and PSi occurred at below 200°C, and PSi underwent self‐multidehydrogenation at above 200°C. These curing reactions gave excellent thermal stability and anticorrosion properties. Compared with pure PSi, the blended containing lower than 20 wt% FR had better thermal properties, manifested as over 390°C of 5 wt% weight loss temperature and over 40% of char yield at 800°C. The adhesion property of cured blended system on the metal surface reached the first level which exceeded that of pure PSi coating (the third level). Furthermore, the corrosion resistances of coating in acid, alkali, and salt environments were all improved compared with those of monomeric polymer coating. The impedance of blended coating in 3.5% NaCl solution decreased with increasing FR content, which was 1.8 × 10⁶ Ω cm² when the FR content was 40%, being higher than that of pure PSi coating (7.12 × 10⁵ Ω cm²). This was mainly due to the formation of a cross‐linked network structure based on Si―O―C bond and the enhanced adhesion of cured blended coating. In addition, the surface roughness of cured blended coating was below 2.0 μm, which may have a positive effect on drag reduction in real applications.     

Functionalized boron carbide for enhancement of anticorrosion performance of epoxy resin

In this study, epoxy coatings were modified by adding various compositions of B₄C particles. In order to achieve proper dispersion of particles in the epoxy coating and increasing chemical interactions between particles and polymeric coating, the surface of the B₄C particles was treated with γ‐(2,3‐epoxypropoxy) propytrimethoxysilane (KH560). The surface modification and microstructure of B₄C were characterized by Fourier transform infrared, X‐ray diffraction, X‐ray photoelectron spectroscopy, scanning electron microscopy, and transmission electron microscopy. Electrochemical impedance spectroscopy was also used to evaluate the impedance of coatings. The results revealed that the KH560 not only enhanced the interaction between B₄C particles and epoxy resin but also exhibited a remarkable ability to improve the anticorrosion performance of epoxy resin. The epoxy coating with the 3 wt% B₄C‐KH560 particles exhibited the best anticorrosion performance, which can be attributed to the best uniform dispersion of the B₄C‐KH560 particles, and the particles effectively block the aggressive species (Cl⁻, O₂, and H₂O) from the coating.     

Synthesis and characterization of phosphorized polyaniline doped with phytic acid and its anticorrosion properties for Mg-Li alloy

A phosphorized polyaniline (PANI) doped with phytic acid (PhA) was synthesized by the chemical oxide method with PhA as a dopant and applied to improve the anticorrosion properties of magnesium-lithium (Mg-Li) alloys after blending with eco-friendly silane sol. The chemical structures and morphologies of PANI samples were evaluated by FTIR spectroscopy, UV-Vis-NIR spectroscopy, X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and scanning electron microscopy (SEM). All characterizations indicate that the as-synthesized phosphorized PANI (PANI-PhA) exists in doped emeraldine salt state with net-like structures crosslinked by phosphate carboxyl groups. The conductivity and thermostability of PANI-PhA were better than those of PANI doped with phosphoric acid (PANI-H₃PO₄) and undoped PANI. The anticorrosion properties of PANI/silane sol composite coatings for Mg-Li alloy were tested by electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization measurements. The results prove that the anticorrosion ability of PANI-PhA is the best among the three PANI samples, as shown by a low corrosion current (1.28 × 10^?7 A·cm^?2) and high impedance (5.62 × 10⁶ Ω·cm²). The possible anticorrosion mechanism was proposed based on procedure analysis.     

600MW级机组湿法脱硫烟囱防腐措施比选研究

通过分析国内湿法脱硫烟囱运行现状与不足,结合某工程600 MW级机组烟囱,从安全可靠、经济适用角度以及电厂工程施工、运行经验等方面综合考虑,对几种不同防腐蚀措施进行技术经济比较,并提出了套筒式悬挂钛钢复合板内筒、玻璃钢内筒的烟囱方案,可为同类型工程项目提供借鉴。     

龙固煤矿主要通风机长效防腐的施工工艺及方法

对矿井主要通风机长效防腐的工艺及方法进行了科学的论证,制定了周密的措施,为通风系统的优化和通风系统的安全经济运行提供了有力的保障,取得了良好的安全效果和经济利益,该技术值得推广和应用。     

PCCP管道输水中套管内安装钢管的施工方法

在完成顶管的套管内安装钢管,是PCCP管道穿越国道、高速、铁路等交叉建筑物的一种有效途径。以大伙房输水二期工程为例,阐述了套管内安装钢管的施工方法,为同类工程项目的施工提供了借鉴。     

水工金属结构防腐方案涂装配套体系的探讨

介绍了涂装配套体系的两种常见方法,论述了涂装配套体系实验数据。     

CTAB表面膜在金属防腐蚀上的应用

本文研究了在碳钢样片上强化制备CTAB表面膜的条件,所制CTAB表面膜的防腐蚀系数平均达到90％以上。经过CTAB表面膜预处理的碳钢样片提高了与氯磺化聚乙烯涂料的附着性能。从而明显地提高了氯磺化聚乙烯涂料的防腐蚀性能。其次,经过CTAB表面膜和氯磺化聚乙烯涂料处理的钢筋与混凝土的粘接系数增加36％,这是适用于钢筋混凝土防腐工程的一个有价值的信息。     

Mg0.9Ti0.1Ni1－xCox (x＝0.05, 0.1, 0.15, 0.2)合金的合成及电化学性能研究

采用机械合金化法合成了Mg_0.9Ti_0.1Ni_1－xCo_x (x＝0.05, 0.1, 0.15, 0.2)系列四元合金, 并对该系列合金的结构和电化学性能等方面进行了研究. 球磨100 h的该系列合金, XRD结果表明, X射线衍射峰均呈现宽化趋势, 基本呈非晶态. 充放电结果表明, 该系列合金具有较好的活化性能, 它们的循环稳定性明显好于MgNi合金, 其中Mg_0.9Ti_0.1Ni_0.8Co_0.2最大放电容量最高, 为427.5 mAh•g^－1. 在充放电循环过程中, Mg在合金表面形成了Mg(OH)₂是合金电极衰减的主要原因. 腐蚀曲线的测试结果表明, Co的添加可以提高合金电极在碱液中的抗腐蚀能力, 从而提高了电极的循环稳定性.     

钢铁表面硅钼杂多酸化学转化膜的研究

本文利用浸渍法在Ａ３钢表面获得具有装饰效果的硅钼杂多酸转化膜。扫描电镜的表面形貌分析，以及３％ＮａＣｌ水溶液中阳极极化曲线均证实该膜层具有较好的耐腐蚀效果。ＸＰＳ和ＡＥＳ的分析结果表明膜层中Ｆｅ（Ⅲ）和Ｆｅ（Ⅱ）两种状态存在，Ｍｏ在膜层外部以Ｍｏ（Ⅵ）存在，内部则以Ｍｏ（Ⅵ）和Ｍｏ（Ⅳ）两种状态存在。从ＡＥＳ深度分布曲线的组成恒定区求得膜层的组成（Ａ．Ｃ．％）为：Ｏ５７．４％，Ｆｅ１７．１％，Ｍｏ