超声球磨改性纳米氢化钛及其环氧涂层的制备

发布时间：2018-08-16 09:35

【摘要】：涂料保护是防止金属腐蚀的最重要与最经济的手段之一,研制高防腐性能的涂料具有十分重要的意义,而在涂料中添加纳米材料提高涂层的性能是当代涂料发展的重要方向。本论文通过超声波辅助球磨法制备了环氧树脂表面接枝改性的纳米氢化钛颗粒,通过X射线衍射、粒径测试、透射电镜、红外光谱与热重分析等方法对超声球磨产物的结构与性能进行表征。在此基础上,将改性纳米氢化钛添加到环氧涂料中制备了纳米复合涂料,对其性能进行测试,并且研究了改性纳米氢化钛的添加量对涂层性能的影响。(1)优化了球磨转速、球料比与球磨时间等工艺参数。得到的最佳工艺参数为：球磨转速650r/min,球料比20:1和球磨时间10h。(2)超声球磨产物的结构与性能表征表明,改性纳米氢化钛颗粒的平均粒径约为80nm,并且颗粒分散较均匀；超声球磨法可实现环氧树脂在纳米颗粒的表面接枝,表面接枝的位置位于环氧基团附近,环氧树脂的表面接枝率约为6.54%;表面接枝改性提高了纳米颗粒在环氧树脂溶液中的分散稳定性。通过无球磨作用的超声波辐照、无超声波作用的搅拌球磨以及超声波辅助球磨的对比试验可知,只有超声波辅助球磨工艺,即超声波与机械力的耦合作用才能实现环氧树脂在纳米颗粒表面的接枝改性。(3)表面改性处理提高了纳米颗粒在涂层中的分散稳定性以及纳米颗粒与环氧基体之间的界面相容性,从而减少了界面缺陷与腐蚀性介质的扩散通道,显著提高涂层的致密度与耐腐蚀性。(4)通过比较不同添加量的涂层的力学性能与耐腐蚀性能可知,当改性纳米氢化钛的添加量低于5wt%时,涂层的性能随着添加量的增大而显著提高；当添加量高于5wt%时,添加量的增大会导致纳米颗粒的部分团聚,反而使涂层性能变差。实验结果表明,5wt%TiH2/环氧树脂纳米复合涂层具有最佳的综合性能。(5)添加改性纳米氢化钛颗粒可提高涂层的性能,首先是因为表面改性处理改善了纳米颗粒与环氧基体的界面相容性与界面结合力,提高了涂层的致密度和抗腐蚀性；其次均匀分散的纳米颗粒可填补涂料固化时产生的结构微孔,隔绝被保护金属基底与外界相连的通道；另外纳米颗粒增加了腐蚀性介质扩散通道的曲折程度,延缓了腐蚀过程。
[Abstract]:Coating protection is one of the most important and economical means to prevent metal corrosion. It is of great significance to develop coatings with high anticorrosive properties. Adding nano-materials to coatings to improve the performance of coatings is an important direction in the development of contemporary coatings. In this paper, nano-titanium hydride particles modified by surface grafting of epoxy resin were prepared by ultrasonic assisted ball milling. X-ray diffraction, particle size measurement, transmission electron microscopy (TEM) were used. The structure and properties of ultrasonic ball milling products were characterized by infrared spectroscopy and thermogravimetric analysis. On this basis, nano-composite coatings were prepared by adding modified nano-titanium hydride into epoxy coatings. The properties of the coatings were tested, and the effects of the amount of modified nano-titanium hydride on the properties of the coatings were studied. (1) the ball milling speed was optimized. Ball material ratio and ball milling time and other technological parameters. The optimum technological parameters are as follows: milling speed 650 r / min, ball material ratio 20:1 and milling time 10 h. (2) the structure and properties of ultrasonic ball milling products show that the average diameter of the modified titanium hydride nanoparticles is about 80 nm, and the particles are dispersed uniformly; The ultrasonic ball milling method can realize the grafting of epoxy resin on the surface of nano-particles, and the position of the surface grafting is near the epoxy group. The surface grafting rate of epoxy resin is about 6.54, and the surface grafting modification improves the dispersion stability of nano-particles in epoxy resin solution. Through the contrast tests of ultrasonic irradiation without ball milling, agitation ball milling without ultrasonic wave and ultrasonic assisted ball milling, it can be seen that only ultrasonic assisted ball milling technology, That is, the coupling of ultrasonic and mechanical force can realize the grafting modification of epoxy resin on the surface of nano-particles. (3) the surface modification improves the dispersion stability of nano-particles in the coating and the interfacial compatibility between nano-particles and epoxy matrix. Thus, the diffusion channels of interface defects and corrosive media are reduced, and the density and corrosion resistance of the coatings are improved significantly. (4) by comparing the mechanical properties and corrosion resistance of the coatings with different amounts of addition, When the content of modified titanium hydride is less than 5wt%, the properties of the coating increase with the increase of the amount of the coating, and when the addition amount is higher than 5wt%, the increase of the amount of the coating will lead to partial agglomeration of the nanoparticles, and the performance of the coating will become worse. The experimental results show that TiH _ 2 / epoxy nano-composite coatings have the best comprehensive properties. (5) the properties of the coatings can be improved by adding the modified nano-titanium hydride particles. Firstly, the surface modification improves the interfacial compatibility and interfacial adhesion between nano-particles and epoxy matrix, and increases the density and corrosion resistance of the coatings. Secondly, the uniformly dispersed nanoparticles can fill the structural micropores produced during the curing of the coating, so as to isolate the protected metal substrate from the channels connected to the outside world. In addition, the nanoparticles increase the tortuous degree of the diffusion channels of corrosive media and delay the corrosion process.
【学位授予单位】：湖南大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TG174.4

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