聚合物的时域介电谱  

Time Domain Dielectric Spectroscopy of Polymers

作　　者：邓颖宇 唐新桂[1] 周镇宏[1] 李景德[1] 

机构地区：[1]中山大学物理学系

出　　处：《中山大学学报（自然科学版）》1996年第2期21-26,共6页Acta Scientiarum Naturalium Universitatis Sunyatseni

基　　金：国家自然科学基金

摘　　要：在１０４至１０－５Ｈｚ频段，聚合物的介电谱只能用时域参数描述．介质的极化响应可描述为Ａεｓｅｘｐ［－（ｔ／τ）类型的若干个项之和．实验证明在随机驰豫中α＝１，在自由驰豫中则α＝１／２．在低频段用频域方法测量εｓ时．样品中的慢响应极化机构的贡献表现为吸收电流；它使得εｓ没有确定值，时域参数是十分灵敏的方法，它可以检测出对εｓ的贡献只有１０－４的微量极化机构．对于同一种聚合物、慢极化响应的成份决定于材料的加工工艺和添加物．in the frequency range of 10-5 to 104 Hz,the dielectric spectroscopy of polymers can be described using time domain parameters. The polarization response of dieletrics may be exeressed as the sum of several terms of Aεs exp[- (t/τ)α]. It is confirmed by experiments that α=1 in stochastic relaxation, and that α= 1/2 in free relaxation processes. When the static dielectric constant εs Is measured in low frequency using frequency domain method, the contribution of slow response to the polarization is presented as absorbing current. The latter leads εs to an uncertain value. Time parameter is shown to be a sensitive method and can detect the microscopic polarization down to 10-4. In polymer material, the component of slow response is shown to be related to the dopants and fabricating process.

关 键 词：介电谱 高聚物 时域参数 介电常数 

分 类 号：O631.23[理学—高分子化学]