聚乙烯吡咯烷酮 - 乙二醇低聚物共混物动力学的宽带介电研究

Broadband dielectric study of dynamics of poly(vinyl pyrrolidone)-ethylene glycol oligomer blends.

作者信息

Shinyashiki N, Sengwa R J, Tsubotani S, Nakamura H, Sudo S, Yagihara S

机构信息

Department of Physics, Tokai University, Hiratsuka, Kanagawa 259-1292, Japan.

出版信息

J Phys Chem A. 2006 Apr 20;110(15):4953-7. doi: 10.1021/jp0605193.

DOI:10.1021/jp0605193

PMID:16610812

Abstract

Broadband dielectric measurements for blends of poly(vinyl pyrrolidone) (PVP) and ethylene glycol oligomer (EGO) from 0 to 40 wt % PVP were carried out at 25 degrees C in the frequency range from 20 Hz to 20 GHz. The EGOs used in this study were ethylene glycol (EG), diethylene glycol (2EG), and PEG400 (MW = 400). For the PVP-EG, -2EG, and -PEG400 blends, relaxation processes caused by the motion of EGO in the GHz range and the micro-Brownian motion of the PVP chain at 10 kHz-1 MHz were observed. Although the PVP-EGO blend is miscible, relaxation processes caused by the molecular motion of EGO and the local chain motion of PVP were observed individually. The relaxation time of the local chain motion of PVP showed a strong PVP concentration dependence and a solvent viscosity dependence, which are similar to those reported so far for the solutions in nonpolar solvents.

摘要

在25摄氏度下，对聚乙烯吡咯烷酮（PVP）含量为0至40 wt%的聚乙烯吡咯烷酮（PVP）与乙二醇低聚物（EGO）的共混物进行了宽带介电测量，测量频率范围为20 Hz至20 GHz。本研究中使用的EGO为乙二醇（EG）、二甘醇（2EG）和聚乙二醇400（MW = 400）。对于PVP-EG、-2EG和-PEG400共混物，观察到了在GHz范围内由EGO运动引起的弛豫过程以及在10 kHz - 1 MHz下PVP链的微布朗运动。尽管PVP-EGO共混物是可混溶的，但分别观察到了由EGO分子运动和PVP局部链运动引起的弛豫过程。PVP局部链运动的弛豫时间表现出强烈的PVP浓度依赖性和溶剂粘度依赖性，这与迄今为止报道的非极性溶剂中溶液的情况相似。