聚合物/纳米碳酸钙复合材料的制备及性能

【作者】 叶露；

【导师】 李效玉；

【作者基本信息】 北京化工大学 ， 高分子化学与物理， 2002， 硕士

【摘要】 碳酸钙作为一种无机填料，被广泛应用于橡胶、涂料、造纸、油墨、印刷、电缆、食品、医药、化妆品、牙膏、饲料、润滑油等各个行业。碳酸钙粉末表面亲水疏油，容易团聚，难以直接应用，必须经过表面处理。长期以来，碳酸钙的应用技术研究多集中在表面处理方面，有一些方法也已获得了工业上的使用。 随着纳米科技的兴起，纳米碳酸钙的生产也已在最近几年已达到了工业化。纳米级的碳酸钙粒子粒径更小，更容易发生团聚，这就对产品的应用提出了新的研究要求。围绕着开发纳米碳酸钙的应用这一中心任务，本论文的工作可以分为两个部分。一、纳米碳酸钙的表面处理及其在塑料中的填充补强；二、纳米碳酸钙在建筑涂料中的应用。具体工作如下： 一、针对纳米碳酸钙填充PVC树脂的应用方向，通过大量的比较实验，确定了丙烯酸酯类共聚物乳液作为纳米碳酸钙的表面改性剂。考察了单体种类、软硬单体比例、第三组分酸的种类与含量、乳化剂、聚合物乳液的固含量等因素对纳米碳酸钙表面改性效果的影响，确定了适宜的聚合反应条件。合成这种聚合物乳液并对纳米碳酸钙进行表面处理，使用透射电镜、XPS、红外、原子力显微镜等方式来考察粒子表面包覆的情况。发现纳米碳酸钙粒子表面均匀地包覆上了一薄层聚合物，并且相互之间分散良好。将这种经过了表面包覆的纳米碳酸钙加入到PVC的合成反应釜中，与氯乙烯发生原位悬浮聚合，得到新型的PVC／nano-CaCO₃复合材料。对聚合所得的粒料进行SEM、TEM观察，发现大量的纳米碳酸钙存在于PVC微球之中，并且呈纳米级的分散状态。对这种粒料进行加工并测试其抗冲性能，发现与纯PVC相比提高了1.5倍。 二、以未经表面处理的纳米碳酸钙浆液为原料，以其中所含有的纳米碳酸钙粒子作为主要的颜填料，配制出一系列新型的建筑乳胶漆。考察了乳液的配方、涂料的配方、配漆的方式对涂料性能的影响，确定了最佳的乳液合成方法和配漆方法。以普通的轻质碳酸钙代替纳米碳酸钙在相同的条件下配制涂料产品作为参比实验，与使用纳米碳酸钙的涂料在多项性能上进行了比较，发现纳米碳酸钙的使用使得涂料的性能得到全面的提高。更多还原

【Abstract】 Calcium carbonate, a common filler, has been used in many fields such as rubber, coating, paper making and commodity. Because the hydrophilic and oil-phobic characteristic of the surface of CaCO3 granule and the apparent inclination to agglomerate, CaCO3 powder cannot be directly used without previous surface modification. Some surface modification methods have been adopted industrially.With the rise of the nanometer science, the produce of nano-CaCCh was fulfilled recently. Since the smaller granule bring the more serious agglomeration, it put forward the new requirement of surface treatment to exploit the application of nano-CaCO3. In order to get this goal, the research was focus on two parts.1 , surface treatment and filling in plasticsAfter a great deal of experiments, the appropriate surfactant is confirmed as an acrylic multipolymer. The right polymerization method is established depending on the study of the effects of monomer, acid, emulsifiers and latex concentration on final composite performance. The treated nano-CaCO3 was added to join the polymerization of chloroethylene monometer. By means of in situ suspension polymerization, the PVC/ nano-CaCO3 composite was obtained. TEM photo shows the dispersion of nano-CaCOa in polymer matrix was perfect and the impact resistance is improved significantly. 2 the application in building coatingThe dispersion of nano-CaCOs in latex is the key to prepare the novel buildingcoating. To solve it, the latex that matches the nano-CaCO3 is synthesized relying on numerous experiments. The test shows many performances of novel coating using the nano-CaCO3 as an important pigment are sharply better than those of common coating using the light CaCO3.更多还原