合成聚苯胺/碳化钨复合材料及聚合机理探讨

采用在原位聚合苯胺的反应介质中分散碳化钨(WC)的方法制备了掺杂聚苯胺/碳化钨(PANI/WC)复合物,并研究了苯胺在WC表面的聚合机理.通过扫描电镜(SEM)、透射电镜(TEM)、傅立叶红外光谱(FTIR)、拉曼光谱(Raman)和X射线衍射(XRD)对复合物进行了表征.结果表明,苯胺的聚合倾向于在WC颗粒表面进行,形成了PANI包覆WC的复合材料;WC粒子与PANI大分子之间存在强的相互作用,并且复合前后WC的晶型并未发生变化,WC的存在导致红外光谱有明显的蓝移现象,复合后在3446 cm-1处的红外吸收峰变得很弱;在拉曼光谱中,代表醌环C N键的伸缩振动峰红移了9 cm-1,并且强度也有很大程度提高.说明PANI与WC之间有化学键的作用,它们之间的化学键作用发生在C N键的N原子上.聚合反应优先在WC粒子表面进行,生成PANI包覆结构,并提出了PANI/WC复合物的形成机制.

SYNTHESIS AND POLYMERIZATION MECHANISM OF POLYANILINE/TUNGSTEN CARBIDE COMPOSITES

Polyaniline/tungsten carbide(PANI /WC) composite was synthesized by chemical oxidative polymerization of aniline in the presence of tungsten carbide(WC) particles,and aniline polymerization mechanism in the surface of WC particles was studied.Then the composites were characterized by means of SEM,TEM,FTIR,Raman and XRD measurements.The results showed that aniline was preferentially polymerized on the surface of WC to form a layer of PANI on the WC surface.Strong interaction existed between PANI and WC particles,and the crystal structure of WC was unchanged in the composites.The FTIR spectra of PANI/WC composites had obvious blue-shift phenomenon due to WC existence,and that the 3446 cm-1absorption peak of the PANI/WC composites became weaker than that of PANI.In the Raman spectra of PANI/WC composites,stretching vibration peak at 1491 cm-1 of quinine ring C N bond had red-shifted 9 cm-1 and the intensity was also largely increased.The results indicated that there was a chemical bond between PANI and WC,and their chemical bond occurred in the N atoms of C N bond.Polymerization took place at the surface of WC particles to form core-shell structure.