【作者】 樊晓萍；

【导师】 周安宁； 葛岭梅；

【作者基本信息】 西安科技大学 ， 矿物加工工程， 2004， 硕士

【摘要】 煤基聚苯胺复合导电材料是利用煤的酸性官能团特征、孔结构特征和芳香层片特征，以煤为模板，用APS引发苯胺单体在煤中原位聚合而成的。其中煤的孔结构和官能团是影响煤/PAN导电性能的重要因素。论文在研究了煤的结构和性质的基础上，从三个方面研究了煤孔结构和官能团变化对煤/PAN导电性能的影响。选择HNO3、H2O2氧化及苯胺抽提的方法改变煤的孔结构；通过电导率、FTIR及孔结构分析表明，氧化和抽提使煤的孔结构变得发达，因而苯胺能更好地进入已溶胀煤的孔结构中，提高了煤基聚苯胺的电导率。采用两种方法研究了官能团变化对煤/PAN电导率的影响。一是通过原煤及氧化煤中的总酸性基的测定、FTIR分析及煤/PAN电导率变化研究，表明煤在氧化过程中，弱的醚键的水解及羧酸盐向羧酸的转化，增加了煤中的羧基和羟基含量。羧基和羟基含量的增加有利于提高煤与苯胺的作用，从而提高复合材料的电导率，其值最高可达4.72×10-1 S/cm。另一种方法是研究了两种在煤/PAN聚合中引入磺酸基的方法，通过电导率对比可知两种方法都有利于提高煤/PAN复合材料的电导率。这是因为质子酸的掺杂使聚苯胺分子内及分子间的电荷离域化增强，电导率大幅度提高。另一方面，磺酸基较大，掺杂到聚苯胺中，降低了聚苯胺分子间的相互作用力，聚苯胺分子以伸展链构象存在，更有利于其电荷离域化，从而使其具有更高的电导率。为了进一步研究煤的孔结构和官能团变化对复合材料电导率的影响，用煤的苯胺抽提物模拟一种有通孔结构，无灰煤作为模板合成煤基聚苯胺复合材料。根据制备高电导率煤/PAN复合材料对煤的要求，可以得到高电导率的复合材料。但复合物最大的电导率为6.46×10-4 S/cm。原因是溶剂抽提产物虽为一种性能优越的天然多孔性材料，但由于其表面的羧基、羰基和羟基等极性基团数量较少，电荷密度较低，活性位点较少，导致其表面“水化”能力较差，难以在水中均匀地分布，不能对聚合物进行良好的掺杂。综合以上几点分析，高电导率的煤/PAN是煤孔结构和官能团的协同效应。更多还原

【Abstract】 Coal/PAN complexes were synthesized by aniline monomer in situ polymerization in coal template initiated by APS, taking advantages of the acidic functional group, pore structure and specific aromatic ring of coal structure. Pore structure and functional groups were the key factors that affect the conductivity of Coal/PAN complexes. Based on the investigation of coal structure and properties, the effect of pore structure and functional groups on the conductivity of Coal/PAN complexes was mainly investigated from three aspects in this dissertation. HNO3, H2O2 and aniline extraction were chosen to change the pore structure in coal. The analysis results of conductivity, FTIR, and pore structure indicated that the conductivity of Coal/PAN was improved by oxidation and extraction, which developed the pore structure in coal, and then facilitated the process of aniline entering the swelled coal pore.Two methods were applied to investigate the effect of the change of functional groups change in coal on the conductivity of Coal/PAN. First, from the analysis of the total acidic groups in row coal and oxidized coal, FTIR, and conductivity change, the hydrolytic decomposition of weak ether bands and the transformation of carboxylate to carboxylic acid during coal oxidation increased the total acidic groups (—OH and —COOH) in coal. The increase of —OH and —COOH groups was benefit to improve the action between coal and aniline, in turn, increased the conductivity of the complex with a maximum of 4.72×10-1 S/cm. Second, two methods of introducing sulfonic groups into coal were investigated. From conductivity comparison, both methods were proved to be benefit to improve the conductivity of Coal/PAN. Proton acids doping caused the inter-molecular and inner-molecular delocalization in PAN and improved the conductivity. On the other hand, the sulfonic groups were relatively large, the inter-molecular action of PAN was decreased with sulfonic groups doping in PAN. The extension state of PAN molecules conformational also enhanced the charge <WP=4>delocalization, and then increased the conductivity.For further investigation of the effect of pore structure and functional groups on the conductivity of Coal/PAN, an aniline extracted product was used as the template to simulate the effect of through pore in free-ash coal on the conductivity of the complex, producing a complex with a maximum conductivity of 6.46×10-4 S/cm. Though the extracted product was a kind of natural porous material with superior performance, in the surface, there were less －OH, －COOH, =C=O, low density electric charge and less active site than that in un-extracted coal, which resulted in a relatively weak "hydration" in the surface. Thus it was difficult to distribute the extracted products in water. And then the polymer doping process was unable to be well done. Synthesizing the above analysis , the cooperation effect of pore structure and functional groups that enhanced the conductivity of Coal/PAN complex.更多还原