【作者】 孙世安；

【导师】 宗志敏；

【作者基本信息】 中国矿业大学 ， 化学工艺， 2014， 博士

【摘要】 腐蚀给各类金属油罐造成不同程度危害，并带来安全隐患。目前，以有机涂层和防锈漆为主的腐蚀防护方法存在着使用寿命短、维护费用高以及重复涂覆施工工作量大等问题。本论文在系统研究金属油罐在自然环境中腐蚀规律的基础上，提出了“终生隔离”防腐理论，开展金属油罐柔性陶瓷基防腐新材料研究，力求实现“一次施工，长效防腐”的目标，对提高金属油罐防腐水平，改善油料保障质量和确保油库运行安全等具有重要的现实意义和经济意义。论文系统研究了金属油罐柔性陶瓷基防腐材料的理想空间结构、固化机理与形成过程。其理想结构是：聚合物与无机胶凝材料在水和多种外加剂的共同作用下，形成一种聚合物-无机胶凝材料互联、贯穿的三维网络独特结构，并且两相之间存在化学键合作用，两种网络在很多点形成较强的黏结，充分发挥复合效应。材料兼具无机材料抗老化性能优异、耐水耐油性好和有机聚合物韧性高、黏结强度大、致密性强等优点。进一步优化材料聚灰比，可得到不同柔韧性能的防腐材料，能满足金属油罐不同部位的防腐要求。探讨了金属油罐柔性陶瓷基防腐材料的基本组成，分析了各主要组分、外加剂与材料力学性能和微观结构之间的关系。通过对不同聚灰比下由NE-1型特种硅酸盐水泥与P·O52.5硅酸盐水泥制备的样品力学性能实验研究发现，加入聚合物乳液后，材料在粘附性、耐冲击性和柔韧性等方面均有了显著改善。通过扫描电子显微镜（SEM）对样品断面分析显示，当聚灰比R≤0.2时，材料体系内的水泥水化后形成了彼此相连的空间骨架，聚合物只能附着在水泥水化产物表面，或被成团阻隔，不能形成网络；当R=0.3~0.5时，无机凝胶材料和聚合物形成了互相贯通、相互依托的空间网络，实现了微观上的两相相容；当R≥0.6时，水泥相被封闭在由聚合物相组成的包裹体中，水泥仅以填料的形式存在，此时复合材料的性能主要取决于聚合物。通过红外光谱分析发现，无机胶凝材料与聚合物能够在分子层面有机结合，所形成的复合材料兼具水泥与丙烯酸酯聚合物的红外光谱特征。通过分析消泡剂对材料性能的影响发现，磷酸三丁酯能显著降低材料在制备过程中产生的孔洞，并且添加量一般应小于等于0.2%。研究不同减水剂减水效果及减水剂添加量对材料性能影响结果表明，随着减水剂加入量的提高，其减水效果逐渐增强，当加入量为1%时效果最好，并且当掺加量相同时，聚羧酸减水剂的减水效果最好，降低用水量达到42.5%，并且，加入减水剂以后材料力学性能有了明显提高。利用扫描电镜（SEM）分析了不同类型孔隙对金属油罐柔性陶瓷基防腐材料致密性的影响规律，通过优化聚灰比和添加高效减水剂等方法提高了材料致密度。压汞法（MIP）分析发现，当材料内不添加聚合物时，材料的总孔容较大，有害孔隙占绝大部分，材料致密性不高；加入聚合物乳液以后，材料中有害孔的数量降至11.7%，总孔容降至0.0752mL/g，材料致密性增强效果更加明显。扫描电子显微镜研究也表明：当材料不含聚合物或聚合物含量较低时，水泥水化产物呈现棒状和拉丝状疏松分布于材料的内部，网状结构中存在较多的毛细孔隙，结构致密性不强；当聚灰比R≥0.3时，材料中的无机相和有机相交叉连接，形成致密的连续空间结构。同时发现，减水剂对材料致密性有显著的改进作用。加入1%的减水剂后，材料孔隙率可降低16.3%，视密度增加28.3%，总孔容降低53.7%。X-射线衍射（XRD）表征显示，聚合物与水泥之间发生了某种定量的物理或化学反应，使得材料的固化过程得到加强，并且，聚羧酸减水剂的添加对水泥水化反应起到促进作用。研究了影响金属油罐柔性陶瓷基防腐材料体积稳定性的主要因素，通过CEA复合膨胀剂实现对材料的体积收缩补偿，通过加入聚丙烯纤维提高了材料的抗微裂纹性能，借助膨胀系数测定仪研究了材料与钢材膨胀/收缩同步一致性。通过分析试样体积变化情况发现，材料在加入CEA复合型膨胀剂后的0~7d内持续膨胀，7d时达到最大，之后出现收缩，90d后基本趋于稳定，当掺入量为10%时，基本可抵消材料固化时产生的体积收缩。研究材料与钢材膨胀/收缩同步一致性发现，随着温度的上升，材料的线膨胀系数与钢材的走势基本一致，并且，随着聚合物含量的增加，一致性有所降低。因此，在满足设计要求的提前下，应尽量控制材料聚灰比在0.5以下。通过研究纤维对材料抗裂性能影响发现，当聚丙烯短纤维加入量在0.8‰~1.0‰时，抗裂效果最好，裂缝降低率可达90%以上。通过耐盐、耐酸、耐碱以及耐油实验研究了材料的耐腐蚀性能。结果表明，当聚灰比在0.3~0.5范围时，材料具有非常高的耐NaCl溶液浸泡、耐H2SO4、NaOH侵蚀和耐航空喷气燃料油浸泡能力。较之环氧富锌防锈漆，所研制的金属油罐柔性陶瓷基防腐材料具有更优异的耐腐蚀性能。分析了金属油罐柔性陶瓷基防腐材料的老化机理，探讨了复合光稳定剂对材料抗老化性能的影响规律，并通过人工加速老化、户外暴露以及冷热交替等方法研究了材料的耐久性。研究不同类型光稳定剂的抗老化效果发现，光稳定剂能显著提升聚合物的抗老化性能，并且，光稳定剂复合使用优于单独使用时的效果，原因是复合体系产生了协同效应，有利于抗老化作用的有效发挥。同时，材料中水泥等无机组分对紫外光具有很强的屏蔽作用，能阻挡紫外线对聚合物的破坏，起到延缓材料老化的作用。整体上，金属油罐柔性陶瓷基防腐材料抗老化能力优异，优于PVDF氟碳涂料。模拟夏冬两季冷热交替过程发现，防腐材料经过720次的冷热循环未出现开裂、粉化或脱落等不良现象，强度几乎没有发生变化，环境适应性好。两年户外暴露试验发现，未涂覆防腐材料的钢板已严重锈蚀，而被双面包裹的样板，则表现出了非常高的耐久性和抗腐蚀性能。更多还原

【Abstract】 Organic coatings or anti-rust paints are the main anti-corrosion materials. However, whenthey are used as anticorrosion material of metallic oil tanks, some problems can not be resolvedsuch as short service life, high maintenance charge and difficult repainting construction. Basedon the corrosion principle of metallic oil tanks in natural environment, an anti-corrosion theoryof―life-long isolation‖was put forward in this work. A kind of flexile ceramic-likeanti-corrosion material used on the surface of metallic oil tanks (FCAM) was studied to achievethe goal of "Once coating, long-term service".The ideal space structure, curing mechanism and forming process were studiedsystematically in this work. The ideal structure of FCAM was like as the following description.With the effect of water and other additives, a three-dimensional network structure was formed,where the polymer and inorganic material connected and crossed each other. The chemical bondsexisted in each or between the two phases of polymer and inorganic material. So, material withthe network structure showed excellent adhesive property and good composite effect.The basic components in FCAM were studied, and the relations between the mechanicalproperty, microstructure and the basic components and additives were also analyzed. Thephysical properties of NE-1and P·O52.5Portland cement with different polymer-cement ratioswere tested in our work. SEM results indicated that a space skeleton instead of network wasformed, and the polymer either attached to the surface of the cement hydration products, or beblocked out of the skeleton and aggregated. Results from Fourier transformed inferredspectrometer indicated that inorganic material could be well combined with the polymeremulsion, and the formed composite material exhibited both features of cement and acrylatepolymers. Tributylphosphate antifoaming agent could reduce the pore numbers formed duringpreparation of the material. Water-reducing agent was another component of the compositematerial. Three types of water-reducing agent were tested to compare their water-reducing effect.Results demonstrated that the effect was obviously improved with the increasing amount. Amongthe three types of water-reducing agent, polycarboxylic acid water-reducing agent could decreasethe water usage and exhibited the best among the three ones. Furthermore, the mechanicalproperty was obviously improved because of the existence of water-reducing agent.The effect of different pores on the compactness and density of FCAM was studied. Thecompactness and density could be improved by optimizing the R values and addition ofwater-reducing agent. The properties of material were compared with the mercury injection test(MIP). When there was not any polymer, the material’s pores were the most part of the totalvolume of the material. When the polymer was added into it, the amount of harmful pores decreased to about11.7%, which enhanced the compactness of the material. Those were alsoconfirmed by scanning electron microscopy (SEM). When the R value was0.3, the compactnessof the material was obviously enhanced, because cement hydrate products were surrounded by afilm formed from solidifying of polymer emulsion, resulting them getting together as a networkwhich made the organic and inorganic phase be linked with each other, to form the continuityspatial structure. Furthermore, the water-reducing agent significantly improved the density of thematerial. X-ray diffraction (XRD) characterization showed that some quantitative physical orchemical reaction took place between the polymer and cement, which made the curing process ofthe material been strengthened. The addition of poly carboxylate reducing agent played asignificant role in promoting the cement hydration process.The main factors of volume stability of FCAM were studied in this work. The volumeshrinkage compensation could achieve by using of composite expansive agent. The resistance tomicro-cracking performance of FCAM was improved by adding of polypropylene fibers. Theexpansion and contraction synchronization consistency between the material and steel wasmeasured by an expansion coefficient instrument. The experimental results showed that after theexpanding agent was added, the material began to continually expand within the first0~7d. Itstarted to shrink after7d and reached a platform until90d. The expanding and shrinkagesynchronization test indicated that the coefficient of linear expansion of the material wasenhanced with the rise of temperature, which was consistent with that of steel. Results showedthat the resistance to micro-cracking performance exhibited the best with the cracking ratedecreasing90%, when the amount of polypropylene fibers was0.8‰~1.0‰.The corrosion resistance of FCAM was studied by salt, acid, alkali and oil resistance tests.Results showed that when the R values were in the range of0.3-0.5, the material has a very hightolerance to NaCl, H2SO4, NaOH and oil solution. Compared with zinc-rich epoxy rust, thedeveloped FCAM had excellent performance and met the design requirements.The mechanism of aging of FCAM was studied and the influence of the composite lightstabilizer on anti-aging properties of the material was also analyzed in this work. By artificiallyaccelerated aging, alternating hot and cold outdoor exposure and other methods, the durability ofthe material was estimated.更多还原