Aziz Shujahadeen B, Abdullah Omed Gh, Rasheed Mariwan A, Ahmed Hameed M
Advanced Polymeric Materials Research Laboratory, Department of Physics, College of Science, University of Sulaimani, Sulaymaniyah 46001, Kurdistan Regional Government, Iraq.
Development Center for Research and Training (DCRT), University of Human Development, Qrga Street, Sulaymaniyah 46001, Kurdistan Regional Government, Iraq.
Polymers (Basel). 2017 May 24;9(6):187. doi: 10.3390/polym9060187.
Chitosan (CS) films doped with sodium triflate (NaTf) were prepared by the solution cast technique. The structural and morphological behaviors of the samples were examined by X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques. The XRD patterns were deconvoluted to estimate the degree of crystallinity of the samples. The SEM micrograph showed the crystalline structure of the sample contained 50 wt % of NaTf salt. The disappearance of broad peaks of chitosan at 2θ ≈ 21° and 2θ ≈ 32° confirmed the occurrence of ion association at 50 wt % of NaTf salt. In impedance plots, a low frequency spike region and a high frequency semicircle, were distinguishable for low salt concentrations. The highest ambient temperature direct current (DC) electrical conductivity obtained for CS:NaTf was found to be 2.41 × 10⁴ S/cm for the sample containing 40 wt % of NaTf salt. The role of lattice energy of salts on DC ionic conductivity was also discussed. The temperature dependence of DC conductivity was found to follow the well-known Arrhenius relationship. From the alternating current (AC) conductivity spectra, three distinct regions were recognized for the samples with NaTf salt concentration ranging from 10 wt % to 30 wt %. The plateau region of AC spectra was used to estimate the DC conductivity.
采用溶液浇铸技术制备了掺杂三氟甲磺酸钠（NaTf）的壳聚糖（CS）薄膜。通过X射线衍射（XRD）和扫描电子显微镜（SEM）技术对样品的结构和形态行为进行了研究。对XRD图谱进行解卷积以估计样品的结晶度。SEM显微照片显示样品的晶体结构含有50 wt%的NaTf盐。壳聚糖在2θ≈21°和2θ≈32°处宽峰的消失证实了在50 wt%的NaTf盐处发生了离子缔合。在阻抗图中，对于低盐浓度，可以区分出低频尖峰区域和高频半圆。对于含有40 wt%的NaTf盐的样品，CS:NaTf获得的最高环境温度直流电（DC）电导率为2.41×10⁴ S/cm。还讨论了盐的晶格能对DC离子电导率的作用。发现DC电导率的温度依赖性遵循著名的阿伦尼乌斯关系。从交流电（AC）电导率谱中，对于NaTf盐浓度范围为10 wt%至30 wt%的样品，识别出三个不同的区域。AC谱的平稳区域用于估计DC电导率。
