【作者】 梁国栋；

【导师】 徐卫兵；

【作者基本信息】 合肥工业大学 ， 材料学， 2003， 硕士

【摘要】 本文采用烷基季铵盐对Ca基蒙脱土进行有机化处理，使其成为有机蒙脱土(Org-MMT)。X射线衍射测试(XRD)表明，有机阳离子已同钙离子发生了交换作用，导致层间距增大。用插层复合法制备聚合物／蒙脱土纳米复合材料，研究聚合物／蒙脱土纳米复合材料的结构和性能。内容包括以下两个部分： 1．采用熔融插层法制备了聚丙烯／接枝物／蒙脱土纳米复合材料，通过XRD、TEM、POM和DSC研究了纳米复合材料的结构及结晶动力学，并测试其力学性能。研究发现： (1)XRD和TEM测试表明，通过熔融插层法，聚合物大分子链已经插层进入蒙脱土片层之间，形成插层型纳米复合材料。 (2)PP／PP-g-MAH／Org-MMT纳米复合材料在蒙脱土含量为2wt％，接枝物含量为10％时拉伸强度出现最大值，和纯PP相比，增加了13％。冲击强度和纯PP接近。 (3)偏光显微镜(POM)测试显示，纯PP球晶大而稀疏，形成完整的黑十字图形。PP／PP-g-MAH／Org-MMT纳米复合材料复合材料中PP的球晶明显细化。X射线衍射测试表明复合材料中聚丙烯111、130、040、041等晶面垂直于反射方向的微晶尺寸随PP-g-MAH含量增加先减小后增大，PP-g-MAH含量为20wt％时最小。 (4)用DSC研究其非等温结晶行为，用Jeziorny和Mo法进行处理。结果表明，Jeziorny和Mo法处理非等温结晶过程比较理想。PP／PP-g-MAH／Org-MMT纳米复合材料的Avrami指数n和F(T)分别大于纯PP的Avrami指数n和F(T)。蒙脱土和PP-g-MAH的加入改变了PP的成核和生长机理，起到了异相成核作用。 2．采用熔融插层法制备了聚乙烯／接枝物／蒙脱土纳米复合材料，通过XRD、TEM和DSC研究了PE／PE-g-MAH／Org-MMT纳米复合材料的结构及结晶动力学，并测试其力学性能。研究发现： (1)XRD和TEM测试表明，采用十八烷基氯化铵改性蒙脱土，通过熔融插层法，聚合物大分子链可以插层进入蒙脱土片层之间，形成剥离型纳米复合材料。 (2)XRD测试显示，采用长链季铵盐、溶液法和高密度聚乙烯可获得较好的插层效果。 (3)用DSC研究HDPE／PE-g-MAH／Org-MMT纳米复合材料非等温结晶行为，用Jeziorny和Mo法进行处理。结果表明，Jeziorny和Mo法处理非等温结晶过程比较理想。HDPE／PE-g-MAH／Org-MMT纳米复合材料的Avrami指数n和F(T)分别大于纯HDPE的Avrami指数n和F(T)。蒙脱土和PE-g-MAH的加入降低了PE的结晶活化能，起到了异相成核作用。更多还原

【Abstract】 In the thesis, organic-montmorillonite(Org-MMT) was obtained by an ion-exchange reaction between Ca-montmorillonite(Ca-MMT) and alkylammonium ion, leading to increase the basal spacing of montmorillonite. X-ray diffraction (XRD) analysis indicated that alkylammonium ions had already exchanged with Ca+ ions in Ca-montmorillonite. Nanocomposites based on polymer and Org-MMT was prepared by melt intercalation, structure and crystallization behavior of nanocomposites were investigated. Two parts were included in this thesis.1. Polypropylene (PP)/PP-g-MAH/Org-MMT nanocomposites were prepared by melt intercalation. XRD, transmission electron micrograph (TEM) and polarized optical micrograph(POM) were used to measure the structure of nanocomposites, the nonisothermal crystallization kinetics of PP/PP-g-MAH/Org-MMT was studied by differential scanning calorimetry (DSC), and their mechanical properties were tested. It was found that:(1) XRD and TEM analysis showed that polymer molecules could intercalate into the interlayer of Org-MMT, leading to the formation of PP/PP-g-MAH/Org-MMT intercalation nanocomposites.(2) The value of tensile strength of PP/PP-g-MAH/Org-MMT nanocomposite was much higher than that of pure PP at the load of 2wt% Org-MMT and 10wt% PP-g-MAH. However, the value of izod impact strength of PP/PP-g-MAH/Org-MMT is close to that of virgin PP.(3) POM analysis showed that spherulitic structure of pure PP is remarkable. Compared with the spherulites of virgin PP, those of PP/PP-g-MAH/Org-MMT nanocomposites with less size were observed. XRD analysis showed that the crystallite size of nanocomposites perpendicular to the crystalline plane like (040), (130),(111),(041) obtained the minimum value when the content of PP-g-MAH is 20 wt%.(4) The nonisothermal crystallization kinetics of PP/PP-g-MAH/Org-MMT was investigated by differential scanning calorimetry with various cooling rates. The Jeziorny and a method developed by Mo could be imployed to describe the nonisothermal crystallization process of PP/PP-g-MAH/Org-MMT nanocomposites very well. The difference of Avrami factor n betweennanocomposites and PP indicated that the nonisothermal crystallization of nanocompostie corresponded to a tridimensional growth with heterogeneous nucleation. The value of F(T) of nancomposites was larger than that of PP, indicating that the crystallization rate of nanocomposite was faster than that of PP. 2. Polyethylene(PE)/PE-g-MAH/Org-MMT nanocomposites were prepared by melt intercalation. XRD, and transmission electron micrograph (TEM) were used to measure the structure of nanocomposites, the nonisothermal crystallization kinetics of PP/PP-g-MAH/Org-MMT was studied by differential scanning calorimetry (DSC), and their mechanical properties were tested. It was found that:(1) XRD and TEM analysis showed that polymer molecules could insert into Org-MMT having been treated by octodecimoalkyl ammonium chloride, and interlayers of Org-MMT were dispersed in HOPE evenly, leading to the formation of HDPE/PE-g-MAH/Org-MMT nanocomposite.(2) XRD analysis showed that better intercalation effect could be obtained by adopting ammonium ion with longer molecule length, solvent method and high density polyethylene.(3) The nonisothermal crystallization kinetics of HDPE/PE-g-MAH/Org-MMT was investigated by differential scanning calorimetry with various cooling rates. The Jeziorny and a method developed by Mo could be employed to describe the nonisothermal crystallization process of PE/PE-g-MAH/Org-MMT nanocomposites very well. The difference of Avrami factor n between nanocomposites and HDPE indicated that the nonisothermal crystallization of nanocompostie corresponds to a tridimensional growth with heterogeneous nucleation. The value of F(T) of nancomposites was larger than that of HOPE, indicating that the crystallization rate of nanocomposite was faste更多还原