Synthesis and dielectric properties of novel liquid crystalline triblock copolymers with cyanobiphenyl moieties and poly(n-butyl acrylate) segments

2014 ◽  
Vol 25 (9) ◽  
pp. 920-926 ◽  
Author(s):  
Cuihong Zhang ◽  
Dongrui Wang ◽  
Jin He ◽  
Tao Liang ◽  
Guo-Hua Hu ◽  
...  
Keyword(s):  
Dielectric Properties ◽  
Butyl Acrylate ◽  
Liquid Crystalline ◽  
Triblock Copolymers

Hierarchical self-assembly, photo-responsive phase behavior and variable tensile property of azobenzene-containing ABA triblock copolymers

RSC Advances ◽  
2015 ◽  
Vol 5 (6) ◽  
pp. 4030-4040 ◽  
Author(s):  
Zai-Zai Tong ◽  
Jin-Qiao Xue ◽  
Rui-Yang Wang ◽  
Jie Huang ◽  
Jun-Ting Xu ◽  
...  
Keyword(s):  
Phase Behavior ◽  
Tensile Property ◽  
Self Assembly ◽  
Butyl Acrylate ◽  
Liquid Crystalline ◽  
Triblock Copolymers ◽  
Hexyl Methacrylate

A series of triblock copolymers with liquid crystalline (LC) poly{6-[4-(4-methoxyphenylazo)phenoxy]hexyl methacrylate} (PMMAZO) as the end blocks and rubbery poly(n-butyl acrylate) (PnBA) as the midblock were synthesized.

scholarly journals Comparison of the Dielectric Properties of Ecoflex® with L,D-Poly(Lactic Acid) or Polycaprolactone in the Presence of SWCN or 5CB

Materials ◽  
2021 ◽  
Vol 14 (7) ◽  
pp. 1719
Author(s):  
Patryk Fryń ◽  
Sebastian Lalik ◽  
Natalia Górska ◽  
Agnieszka Iwan ◽  
Monika Marzec
Keyword(s):  
Oleic Acid ◽  
Dielectric Properties ◽  
Polymer Matrix ◽  
Liquid Crystalline ◽  
Weight Ratio ◽  
Poly Lactic Acid ◽  
Relaxation Processes ◽  
The Matrix ◽  
Walled Carbon Nanotubes ◽  
Hybrid Layers

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.

Dielectric properties of alumina-filled poly (ethylene-co-butyl acrylate) nanocomposites Part II- wet studies

2012 ◽  
Vol 19 (2) ◽  
pp. 391-399 ◽  
Author(s):  
N. Javerberg ◽  
H. Edin ◽  
P. Nordell ◽  
S. Nawaz ◽  
H. Hillborg ◽  
...  
Keyword(s):  
Dielectric Properties ◽  
Butyl Acrylate ◽  
Poly Ethylene

Dielectric properties of a hydrogen-bonded liquid-crystalline side-chain polymer

1995 ◽  
Vol 16 (10) ◽  
pp. 733-739 ◽  
Author(s):  
Kazuo Araki ◽  
Takashi Kato ◽  
Uday Kumar ◽  
Jean M. J. Fréchet
Keyword(s):  
Dielectric Properties ◽  
Liquid Crystalline ◽  
Side Chain ◽  
Chain Polymer ◽  
Hydrogen Bonded

ChemInform Abstract: Liquid-Crystalline Imidazo(2,1-b)-1,3,4-thiadiazoles. Part 3. Synthesis and Dielectric Properties of Imidazo(2,1-b)-1,3,4-thiadiazoles with Polar Substituents.

ChemInform ◽  
1988 ◽  
Vol 19 (48) ◽  
Author(s):  
S. I. TORGOVA ◽  
N. M. SHTYKOV ◽  
A. G. ABOLIN ◽  
L. A. KARAMYSHEVA ◽  
A. V. IVASHCHENKO ◽  
...  
Keyword(s):  
Dielectric Properties ◽  
Liquid Crystalline ◽  
Polar Substituents

scholarly journals Cubic and tetragonal liquid crystal phases composed of non-chiral molecules: Chirality and macroscopic properties

2019 ◽  
Vol 42 (11) ◽  
Author(s):  
Helmut R. Brand ◽  
Harald Pleiner
Keyword(s):  
Liquid Crystal ◽  
Liquid Crystalline ◽  
Triblock Copolymers ◽  
Similar Type ◽  
Chiral Molecules ◽  
Chiral Compounds ◽  
Liquid Crystalline Phases ◽  
Symmetry Properties ◽  
Crystal Phases ◽  
Liquid Crystal Phases

Abstract. We discuss the symmetry properties as well as the macroscopic behavior of the cubic liquid crystal phases showing large chiral domains of either hand in some non-chiral compounds reported recently in the group of Tschierske. These phases are tricontinuous. While they have O or I432 symmetry in each chiral domain, the overall symmetry is $ I m \bar{3} m$Im3¯m as there is no net chirality for compounds composed of non-chiral molecules. It turns out that a rather similar type of phase has also been reported for triblock copolymers. Here we analyze in detail the macroscopic static and dynamic behavior of such phases and we predict, among other results, that they show the analog of static and dissipative Lehmann-type effects in their chiral domains. A description of a cubic liquid crystalline phase of Th symmetry, which has not yet been found experimentally, is also included. Suggestions for experiments are outlined to identify such a phase. In addition, we discuss tetragonal liquid crystalline phases of D4h and D4 (I422) symmetry as they have been reported last year experimentally in connection to the Q phase. Graphical abstract

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