中文摘要：

针对柔性聚合物基导电复合材料的导电性差和柔性差这2个关键问题,分别从导电填料的柔性化及降低填料含量2方面着手,以脱氧核糖核酸（DNA）大分子链作为模板,制备了大小均一、链状排列的柔性纳米Ag链及纳米Ag链填充的聚氨酯基柔性导电复合材料。利用SEM对纳米Ag链/Ag包Cu粉/聚氨酯导电复合材料的界面结构进行了表征,探讨了纳米Ag链/Ag包Cu粉/聚氨酯导电复合材料导电性及柔性的机制。研究发现：保持导电填料总质量分数为76%、纳米Ag链的质量分数为4%时,纳米Ag链/Ag包Cu粉/聚氨酯导电复合材料的电阻率及形变前后的电阻变化比值达到最佳值,分别为2.13×10^（-4）Ω·cm和3.6;当以纳米Ag链为单一填料时,制得的纳米Ag链/聚氨酯导电复合材料具有优异的柔性;泡沫法制备的纳米Ag链/聚氨酯导电复合材料可以在低填料质量分数时达到更高的导电性,当纳米Ag链质量分数为60%时,方阻为56Ω/sq,低于共混法制备的填料质量分数为65%时的纳米Ag链/聚氨酯导电复合材料（98Ω/sq）。

英文摘要：

In consideration of the two key issues for the poor conductivity and poor flexibility of flexible polymer matrix conductive composites,flexible conductive fillers were prepared and the amount of fillers were reduced to solve these issues simultaneously.Deoxyribonucleic acid （DNA）molecule chains were utilized as template to fabri-cate Ag nanochains and Ag nanochains filled polyurethane-based flexible conductive composites.The interface struc-tures of the Ag nanochains/Ag-coated Cu flakes/polyurethane conductive composites were studied by SEM.The mechanism of the conductivity and flexibility for Ag nanochains/Ag-coated Cu flakes/polyurethane conductive com-posites were discussed.Research shows that when the total mass fraction of conductive fillers is keep at 76% and the mass fraction of Ag nanochains is 4%,the optimum resistivity and the resistance change ratio of Ag nanochains/Ag-coated Cu flakes/polyurethane conductive composites before and after deformation were achieved,which are 2.13×10-4 Ω·cm and 3.6 respectively.When the Ag nanochains were used as single fillers,the Ag nanochains/polyurethane conductive composites possess excellent flexibility.The Ag nanochains/polyurethane conductive com-posite prepared by foam template method achieves better conductivity at lower filler mass fraction.When the mass fraction of Ag nanochains is 60%,the sheet resistance is 56Ω/sq,less than that of the Ag nanochains/polyurethane conductive composites prepared by blending method whose mass fraction of filler is 65% （98 Ω/sq）.