防污涂层的纳米微结构制备与防污性能研究

防污涂层的纳米微结构制备与防污性能研究

国防科学技术大学

硕士学位论文

姓名：田小洲

申请学位级别：硕士

专业：应用化学

指导教师：王建方

2010-11

国防科学技术大学研究生院硕士学位论文

摘要

随着全球环保呼声的日益高涨，开发新型无毒、安全高效的防污涂料已迫在眉睫。本文的研究受到自然界生物防污方式的启发，模仿荷叶表面，在制备低表面能聚合物的同时，重点研究表面微结构的构建及其对防污性能的影响。

本文首先通过原位聚合法制备了与纳米粒子结合良好的有机氟

改性聚丙烯酸酯NP-FPA，并与异氰酸根封端的有机硅改性聚氨酯SPU 交联，在涂膜交联的同时，自动形成表面微结构。分别采用FT-IR，GPC和旋转粘度计对两组分进行了结构、分子量以及粘度的分析表征。精确测定了NP-FPA中的羟基含量和SPU中的异氰酸根含量。在此基础上，选择NCO : OH（当量比）=1.10 : 1将SPU与NP-FPA混合，通

过交联反应得到了兼具有机硅和有机氟优点的新型聚合物，并对其进

行了结构表征。

其次，重点研究了表面微结构设计、构建和表征。采用不同的纳米粒子如SiO2、Fe3O4、TiO2等，和不同的比例1%~7%在低表面能涂层表面构建表面微结构，研究了纳米粒子的加入种类和比例对表面微结构的影响；采用化学腐蚀法在铜基片表面形成了微结构，对其进行低表面能修饰同样得到了具有微结构的低表面能涂层，用以对比考察表面微结构对防污性能的影响。为了使纳米粒子在涂层中具有较好的分散性，分别利用硅烷偶联剂和表面活性剂对纳米粒子进行了表面改性，并对改性效果进行了粒径和表面形貌观察。通过改变纳米粒子种类和添加量对微结构进行调控，利用SEM和AFM对构建的微结构进行表面形貌观察，结果发现纳米粒子种类和添加量都对微结构有很大影响。

最后，对制备的具有微结构的低表面能防污涂层进行了性能研究。以与水的接触角和与模拟胶的剥离强度为考察指标，采用正交实验的方法筛选出了最优化的纳米粒子种类和添加量：添加量为5%的纳米Fe3O4复合涂层具有最优的防污性能，与水接触角最大达121°，剥离强度最小为6.0 N/m。并对添加Fe3O4纳米粒子的复合涂层进行了常规力学性能的研究，结果表明制备的含Fe3O4纳米粒子的防污涂层各项指标均达到或高于国家标准。

本文的研究结果表明，在低表面能聚合物基础上，表面的微结构可以显著改变其疏水性，进而影响到防污性能，本文的接触角试验和模拟胶剥离试验以及铜片腐蚀构造的微结构表面对比试验等证实了

这一点。而模仿荷叶结构构造的微/纳二级结构能最大限度的减少与附着物的接触面积，从而有效的提高防污性能。

关键词：表面微结构；低表面能；原位聚合法；剥离强度；Fe3O4纳米粒子

国防科学技术大学研究生院硕士学位论文

ABSTRACT

Since more and more attention was paid to environment protection in the whole world, the antifouling coatings which are non-toxic, safe and effective is staring us in the faces. With the highlight of antifouling methods in nature, the surface of lotus leaf was mimicked. The polymer with low surface energy was prepared, simultaneously; it was taken as a key point to study the building of surface microstructure and its effect to antifouling property.

Firstly, NP-FPA, which was organic fluorine modified polyacrylate combined well with nano-particles, was prepared by in-situ polymerization. And then, NP-FPA was crosslinked with SPU, which was organic silicon modified polyurethane terminated by isocyanate. The surface microstructure was formed automatically while crosslinking. The structure, molecular weight and viscosity of the two components were characterized by FT-IR, GPC and rotary viscometer, respectively. The content of hydroxyl in NP-FPA and the content of isocyanate in SPU were exactly determined. Hereon, SPU and NP-FPA were mixed when NCO :

OH (equivalence ratio) = 1.10 : 1. A novel polymer with the advantages of both organic silicon and organic fluorine was prepared by cross-linking reaction, and the structure was characterized.

Secondly, the design, build and characterization of surface microstructure were taken as the key points to study. Surface microstructure was built on the surface of coating with low surface energy adopting different nano-particles including SiO2, Fe3O4, TiO2, etc. ranging from 1%~7%, and the effect of types and scales of nano-particles was studied. Chemical etching method was used to build microstructure in copper surface, and then modified by low surface energy. As a result, the coating with the same microstructure and low surface energy was prepared. Thus, it was used to study the effect of surface microstructure to antifouling property contrastively. In order to acquire better dispersion of nano-particles in the coating, the nano-particles surfaces were modified by silane coupling agent and surfactant, respectively. The grain size and the surface morphology were observed to identify the effectiveness of the modifications. The microstructures were controlled by the type and quantity of nano-particles, and the surface morphologies of the microstructures were performed by SEM and AFM. The results showed that the type and quantity of nano-particles affected the microstructure greatly.

Finally, the properties of the antifouling coatings prepared with