Fryń Patryk, Lalik Sebastian, Górska Natalia, Iwan Agnieszka, Marzec Monika
Institute of Physics, Jagiellonian University, S. Lojasiewicza 11, 30-348 Krakow, Poland.
Faculty of Chemistry, Jagiellonian University, Gronostajowa 2, 30-387 Krakow, Poland.
Materials (Basel). 2021 Mar 31;14(7):1719. doi: 10.3390/ma14071719.
The main goal of this paper was to study the dielectric properties of hybrid binary and ternary composites based on biodegradable polymer Ecoflex, single walled carbon nanotubes (SWCN), and liquid crystalline 4'-pentyl-4-biphenylcarbonitrile (5CB) compound. The obtained results were compared with other created analogically to Ecoflex, hybrid layers based on biodegradable polymers such as L,D-polylactide (L,D-PLA) and polycaprolactone (PCL). Frequency domain dielectric spectroscopy (FDDS) results were analyzed taking into consideration the amount of SWCN, frequency, and temperature. For pure Ecoflex, two relaxation processes (α and β) were identified. It was shown that the SWCN admixture (in the weight ratio 10:0.01) did not change the properties of the Ecoflex layer, while in the case of PCL and L,D-PLA, the layers became conductive. The dielectric constant increased with an increase in the content of SWCN in the Ecoflex matrix and the conductive behavior was not visible, even for the greatest concentration (10:0.06 weight ratio). In the case of the Ecoflex polymer matrix, the conduction relaxation process at a frequency ca. several kilohertz appeared and became stronger with an increase in the SWCN admixture in the matrix. Addition of oleic acid to the polymer matrix had a smaller effect on the increase in the dielectric response than the addition of liquid crystal 5CB. Fourier transform infrared (FTIR) results revealed that the molecular structure and chemical character of the Ecoflex and PCL matrixes remained unchanged upon the addition of SWCN or 5CB in a weight ratio of 10:0.01 and 10:1, respectively, while molecular interactions appeared between L,D-PLA and 5CB. Moreover, adding oleic acid to pure Ecoflex as well as the binary and ternary hybrid layers with SWCN and/or 5CB in a weight ratio of Ecoflex:oleic acid equal to 10:0.3 did not have an influence on the chemical bonding of these materials.
本文的主要目标是研究基于可生物降解聚合物Ecoflex、单壁碳纳米管（SWCN）和液晶4'-戊基-4-联苯甲腈（5CB）化合物的二元和三元混合复合材料的介电性能。将所得结果与其他类似Ecoflex制备的、基于可生物降解聚合物如L,D-聚乳酸（L,D-PLA）和聚己内酯（PCL）的混合层进行比较。考虑到SWCN的含量、频率和温度，对频域介电谱（FDDS）结果进行了分析。对于纯Ecoflex，确定了两个弛豫过程（α和β）。结果表明，SWCN混合物（重量比为10:0.01）并未改变Ecoflex层的性能，而在PCL和L,D-PLA的情况下，这些层变得具有导电性。随着Ecoflex基体中SWCN含量的增加，介电常数增大，即使对于最大浓度（重量比为10:0.06），也未观察到导电行为。在Ecoflex聚合物基体中，在约几千赫兹的频率下出现了传导弛豫过程，并且随着基体中SWCN混合物的增加而变强。向聚合物基体中添加油酸对介电响应增加的影响小于添加液晶5CB。傅里叶变换红外（FTIR）结果表明，分别以10:0.01和10:1的重量比添加SWCN或5CB后，Ecoflex和PCL基体的分子结构和化学性质保持不变，而L,D-PLA和5CB之间出现了分子相互作用。此外，以Ecoflex:油酸等于10:0.3的重量比向纯Ecoflex以及含有SWCN和/或5CB的二元和三元混合层中添加油酸，对这些材料的化学键合没有影响。
