【作者】 潘民选；

【导师】 熊传溪；

【作者基本信息】 武汉理工大学 ， 材料学， 2010， 硕士

【摘要】 本文在查阅了大量关于PVC改性,NBR配位硫化和高岭土改性及在塑料中的应用研究等资料的基础之上,采用熔融共混的方法分别制备了PVC/NBR /CuSO4·5H2O复合材料和PVC／改性高岭土复合材料。结果表明,两种复合材料均具有较好的抗冲性能和耐热性能。其实验研究结果主要总结如下：首先制得了两种比例的NBR/CuSO4·5H2O共混物,FTIR、溶解性和力学性能测试表明材料内部出现了交联。将该共混物与PVC及加工助剂在密炼机中熔融共混,制备了PVC/NBR/CuSO4·5H2O复合材料。加工性能和力学性能分析表明,NBR/CuSO4·5H2O共混物的加入改善了复合体系加工性能,力学性能也得到了很大的提高,加入3wt%该共混物即可使复合材料的拉伸强度和冲击强度较纯PVC提高9.4%和18.3%,但断裂伸长率则随共混物含量的增加呈下降趋势；耐热性能分析表明,共混物的加入可以抑制复合材料的高温降解,提高其玻璃化转变温度；对复合材料的冲击断面形貌观察发现,其断面出现了许多纳米级的类纤维丝棒状物质并穿插于PVC基体中,这一特殊形貌尚是首次发现。在制备PVC／改性高岭土复合材料过程中,首先采用偶联剂处理法和大分子表面处理剂(DF)表面包覆法分别对高岭土进行了改性。FTIR表明偶联剂与高岭土发生了反应,DF也成功的包覆在了高岭土表面,极性测试表明改性后高岭土均由原来的亲水性变为疏水性,XRD分析表明改性高岭土的结构没有发生变化。其次,将改性高岭土与PVC熔融共混制备了PVC／改性高岭土复合材料。加工性能分析表明,改性高岭土的加入缩短了复合体系的塑化时间,且平衡扭矩减小；拉伸性能和冲击性能测试表明,适量的改性高岭土可以对复合体系起到增韧增强的作用,其中以表面包覆改性高岭土的效果最好,添加5wt%的该改性高岭土的PVC复合材料,其拉伸强度比纯PVC提高了9.3%,冲击强度则由原来的51KJ／m2提高到113.4 KJ／m2以上,提高幅度达两倍以上；耐热性能测试表明,改性高岭土的加入对复合材料初期热分解影响较小,但提高了复合材料的玻璃化转变温度；SEM观察表明,采用DF表面包覆法改性的高岭土与PVC的相容性较好。更多还原

【Abstract】 On the basis of consulting plenty of references about poly (vinyl chloride) (PVC) modification, NBR coordination crosslinking, kaolinite modification and application in plastic. PVC/NBR/CuSO4·5H2O and PVC/modified kaolinite composites were prepared by melt mixing. The results showed that these composites both had better heat resistance and impact strength than pure PVC. The main experimental results can be summarized as follows:Firstly, two varying ratios NBR/CuSO4·5H2O compounds were prepared. FTIR, solubility and mechanical properties analysis showed crosslinking structure formed in the materials after heat pressing. Secondly, the PVC/NBR/CuSO4·5H2O composites were prepared by melt mixing with NBR/CuSO4·5H2O compounds, PVC and processing aids in internal mixer. Processing and mechanical properties analysis displayed that processing properties of PVC/NBR/CuSO4·5H2O composites was improved with NBR/Cu-SO4·5H2O compounds contents increased. With adding 3 wt% NBR/CuSO4·5H2O compounds into the composites, tensile strength and impact strength of the composites significantly increased by 9.4% and 18.3% respectively, but the elongation at break decreased with increasingly increased compounds contents. Heat resistant analysis showed that the high temprerature degradation of composites could be restrained and the glass transition temperature increased after adding NBR/CuSO4·5H2O compounds. The impact fracture surfaces of composites analysis indicated that a number of nano-sized fibers wire rod emerged on the fracture surfaces, and these nano-sized fibers firmly inserted into the PVC matrix. The special morphology was first found in the research.During the preparation processes of PVC/modified kaolinite composites, firstly, original kaolinite was modified with coupling agent and macromolecule surface-coated modifier (DF). FTIR showed that the coupling agents could graft onto kaolinite surface, and DF was also successfully coated around the kaolinite surface. Polarity analysis displayed that the modified kaolinite became hydrophobic from original hydrophilic. XRD analysis indicated that the modification did not change the structure of kaolinite. Secondly, PVC/modified kaolinite composites were prepared by melt mixing. Processing properties analysis showed that both plasticizing time and balance torques of the composites were reduced with adding modified kaolinite. Tensile and impact properties analysis indicated that the appropriate amount of modified kaolinite could toughen and strengthen the composites. However, the surface-coated modified kaolinite had a better effect than coupling agent modified kaolinite. When its content was 5 wt%, the tensile strength of the PVC/surface-coated kaolinite composites could increase by 9.3% than pure PVC, while the impact strength was increased to 113.4 KJ/m2 from the 51KJ/m2, the increment was twice times. Heat resistant analysis displayed that the modified kaolinite addition had little influence on the initial thermal decomposition tenperatuure of composites, but the glass transition temperature significantly increased. SEM photographs showed that surface-coated kaolinite had a better compatibility with PVC than coupling agent modified kaolinite.更多还原