A polyurethane (PUR)/hydroxyl-functionalized multi-walled carbon nanotubes (MWNTs-OH) composite conduct-ing materials were prepared via an in-sit polymerization reaction with taking hydrolysis modification hydroxyl-termnated polybutadi-ene (h-HTBN) as soft segment,diphenylmethane diisocyanate (HDI) as hard segment,1,4-butanediol (BDO) as chain extender and MWNTs-OH as conductive carrieer. The structural characterization of the conducting materials were conducted by means of FTIR and SEM,and the dispersion stability tests were used to illustrate the coating effect of polyurethane on MWNTs-OH. The conductive materials and electrodes were assembled into thesensing elements,and the vapor response performances of the sensing element were evaluated using the vapors of different solvents (benzene,anhydrous ether,acetone and chloroform). The results indicate that the composite conducting materials display a good vapor selectivity and repeated stability for benzene and chloroform solvent vapors, this is mainly ascribed to the micro-phase separation phenomena of PUR composition,lipophilic solvent can interact with amorphous micro domain of soft segment and destory the conductive path formed by MWNTs-OH,which leads to the increase of resistance and induces vapor response.%以羟基多壁碳纳米管(MWNTs-OH)作为导电载流子，以水解改性的端羟基聚丁二烯–丙烯腈共聚物(h-HTBN)作为软段，六亚甲基二异氰酸酯(HDI)作为硬段，1，4-丁二醇(BDO)作为扩链剂，通过原位聚合方法制备了聚氨酯(PUR)／MWNTs-OH复合导电材料。通过傅立叶变换红外光谱和扫描电子显微镜对复合导电材料进行了结构表征，并采用分散稳定性实验证明了PUR对MWNTs-OH的包覆效果。将复合导电材料与电极片组装制作成传感元件，测试其对4种不同溶剂(苯、无水乙醚、丙酮和氯仿)的气敏响应性。结果表明，合成的PUR／MWNTs-OH复合导电材料对苯和氯仿等亲油性溶剂具有良好的气敏选择性和重复稳定性，这主要是由于PUR结构中存在微相分离现象，亲油性溶剂能够与软段形成非晶微区相互作用，破坏了MWNTs-OH导电粒子形成的路径，导致电阻升高，引起气敏响应。
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