The ionization − assisted method was used to prepare villyl polymer films of tetraphenyl − diam血obiphenyl ( TPD ) . The electron irradiation in t瓱 e deposit 重 on prooess was effective to en ハ anco the polym ¢ r孟 zation reaction . Thc reaction appears to be driven by neutral radicals produccd by the eiectron irradiation . The polymerization was also enhanced by increas 孟 皿 g the substrate temperatUre during the deposi 口on , and by pos 卜 a ealing in vacuum . At an appropriate condition , the

more »

... ge molecular weight of 22xlOa was obtained at the y 孟 eld of 91% . The po 産 ymerized film of TPD − ac was applicable as 出 e hole瞰 1spo 蛇 layer of o π ganic EL devices. The device performance was improved