时域谱和二甲基硅油的玻璃化转度

The Glass Transition and Time Domain Spectrum of Polymethylsiloxane

测量了聚合度由５０～８２４的二甲基硅油的频域和时域低温介电谱，其结果和聚合度几乎无关．在－１２０℃的玻璃化转变中频域损耗只有一个小峰，但时域慢介电常数却出现显著的强峰，由分子的螺旋结构解释了实验结果．

The frequency and time domain dielectric spectra of polydimethylsiloxane of polymerization degree 50 to 824 are measured in low temperature.The results are independent of polymerization degree.In glass transition near -120 ℃ the frequency loss is shown to present a peak;and the time domain slow dielectric constant presents a higher peak in the same temperature.The results are explained using the screwed structures of molecules.