scholarly journals Polymorphism in N,N′-dialkyl-naphthalene diimides

2020 ◽  
Vol 8 (9) ◽  
pp. 3097-3112 ◽  
Author(s):  
Silvia Milita ◽  
Fabiola Liscio ◽  
Lewis Cowen ◽  
Massimiliano Cavallini ◽  
Ben A. Drain ◽  
...  
Keyword(s):  
Thin Films ◽  
Liquid Crystalline ◽  
Imaging Techniques ◽  
Polymorphic Behavior ◽  
Thermally Induced ◽  
Naphthalene Diimides

N-Alkyl naphthalene diimides show a highly versatile thermally-induced polymorphic behavior, including liquid crystalline mesophases, fully characterized in powders and thin films by combining thermal, diffraction and imaging techniques.

Fracture behavior of heat treated liquid crystalline polymers

2012 ◽  
Vol 1485 ◽  
pp. 137-142 ◽  
Author(s):  
A. Reyes-Mayer ◽  
B Alvarado-Tenorio ◽  
A Romo-Uribe ◽  
O Flores ◽  
B Campillo ◽  
...  
Keyword(s):  
Thin Films ◽  
Thermal Treatment ◽  
Thermal Behavior ◽  
Fracture Behavior ◽  
Liquid Crystalline ◽  
Liquid Crystalline Polymers ◽  
Thermally Induced ◽  
Crystalline Polymers ◽  
Heat Treated ◽  
Mechanical Modulus

ABSTRACTThermotropic polymers are thermally treated in air at temperatures Ta, where ΔT =Ta- Ts→n=40°C, and Ts→n is the solid-to-nematic transition. Samples are extruded thin films of a series of thermotropic random copolyesters termed B-N, COTBP and RD1000. The thermal treatment produces a second endotherm without changing Ts→n for B-N and RD1000. However, for COTBP Ts→n is significantly increased. Regardless of the complex thermal behavior exhibited by the thermotropes, the thermal treatment produces a significant increase in Young's modulus, more than 30% for B-N and over 100% for COTBP. The increase in mechanical modulus is correlated with a thermally-induced fiber-like morphology.

Phase Separation in Liquid-Crystalline Copolymer/Poly(methyl methacrylate) Blends

1995 ◽  
Vol 60 (11) ◽  
pp. 1869-1874 ◽  
Author(s):  
Anatoly E. Nesterov ◽  
Yuri S. Lipatov ◽  
Vitaly V. Horichko
Keyword(s):  
Phase Separation ◽  
Methyl Methacrylate ◽  
Liquid Crystalline Polymer ◽  
Liquid Crystalline ◽  
Ethylene Terephthalate ◽  
Crystalline Polymer ◽  
Scattering Method ◽  
Thermally Induced ◽  
Poly Methyl Methacrylate ◽  
Copolymer Poly

The phase separation in the blends of poly(methyl methacrylate) and liquid-crystalline polymer (copolymer of ethylene terephthalate and p-hydroxybenzoic acid) has been studied by the light scattering method and the cloud point curves have been obtained. Simultaneously some morphological features of the blends have been observed. It was found that the initial blends are in the state of forced compatibility and that thermally induced phase separation occurs by the mechanism of spinodal decomposition but presumably in the non-linear regime.

Synthesis and characterization of silver nanoparticle nanocomposite thin films with thermally induced surface morphology changes

2015 ◽  
Vol 159 ◽  
pp. 118-121 ◽  
Author(s):  
Ernandes T. Tenório-Neto ◽  
Marcos R. Guilherme ◽  
Manuel E.G. Winkler ◽  
Lucio Cardozo-Filho ◽  
Stéphani C. Beneti ◽  
...  
Keyword(s):  
Thin Films ◽  
Surface Morphology ◽  
Silver Nanoparticle ◽  
Synthesis And Characterization ◽  
Thermally Induced ◽  
Nanocomposite Thin Films ◽  
Morphology Changes

Effect of Block Copolymer Architecture on the Thermally Induced Swelling of Micelle-Containing Multilayer Thin Films

2011 ◽  
Vol 44 (19) ◽  
pp. 7767-7774 ◽  
Author(s):  
Wui Siew Tan ◽  
Zhichen Zhu ◽  
Svetlana A. Sukhishvili ◽  
Michael F. Rubner ◽  
Robert E. Cohen
Keyword(s):  
Thin Films ◽  
Block Copolymer ◽  
Multilayer Thin Films ◽  
Thermally Induced

Tunable topographical cellulose matrices for electro-optical liquid crystal cells

2006 ◽  
Vol 14 (4) ◽  
Author(s):  
I. Costa ◽  
P. Almeida ◽  
D. Filip ◽  
J. Figueirinhas ◽  
M. Godinho
Keyword(s):  
Thin Films ◽  
Liquid Crystal ◽  
Liquid Crystalline ◽  
Cellulose Derivatives ◽  
Free Standing ◽  
Casting Technique ◽  
Solvent Vapour ◽  
Preparation Conditions ◽  
And Control ◽  
Crystal Cells

AbstractIn this work we have used acetoxypropylcellulose (APC) to produce free standing solid films (∼60 μm) that were used for assembling electro-optical devices. Thin films were obtained from concentrated lyotropic solutions of cellulose derivatives. Induced by the cast and shearing preparation conditions wrinkles and band textures can be observed in their free-surface plane. In order to eliminate and control these textures we used a process similar to that introducted in literature [1] which consists of storing the films in the same solvent-vapour atmosphere as the solution system. Lyotropic APC liquid crystalline solutions in dymethylacetamide (DMA) with crosslinker were prepared, thin films were obtained by using a shear/casting technique and stored in the solvent-vapour atmosphere until a planar structure was achieved. The dried crosslinked films were analyzed by optical polarised microscopy (POM) and scanning electron microscopy (SEM). The films with different topographies were used to produce optical cells composed by the cellulose derivative film covered on both free surfaces by a layer of the nematic liquid crystal E7 and placed between two transparent conducting substrates. The electro-optical properties of these cells were obtained.

Synthesis and Characterization of Terthiophene-Based Rod-Like Liquid Crystals

2012 ◽  
Vol 532-533 ◽  
pp. 61-65
Author(s):  
Xiao Hui Liu ◽  
Zhong Xiao Li ◽  
Song Ya Zhang ◽  
Jia Ling Pu
Keyword(s):  
Liquid Crystal ◽  
Liquid Crystalline ◽  
Crystal Phase ◽  
Liquid Crystal Phase ◽  
Schiff’S Base ◽  
Thermally Induced ◽  
H Nmr ◽  
Clearing Point ◽  
Temperature Ranges

With 2,2',5',2''-Terthiophene as starting material, two liquid crystalline compounds containing Schiff’s base unit were synthesized in this paper. The structure of the compounds was confirmed by FTIR and 1H NMR. The thermally induced phase transition behaviors were investigated by POM and DSC, and the temperature ranges of liquid crystal phase of the two compounds were compared. Results showed that the symmetric compound exhibited a lower clearing point temperature and broader temperature range of liquid crystal phase.

scholarly journals Vapor deposition routes to conformal polymer thin films

2017 ◽  
Vol 8 ◽  
pp. 723-735 ◽  
Author(s):  
Priya Moni ◽  
Ahmed Al-Obeidi ◽  
Karen K Gleason
Keyword(s):  
Thin Films ◽  
Chemical Vapor Deposition ◽  
Sample Preparation ◽  
Vapor Phase ◽  
Vapor Deposition ◽  
Imaging Techniques ◽  
Polymer Thin Films ◽  
Chemical Vapor ◽  
Short Review ◽  
Deposition Sample

Vapor phase syntheses, including parylene chemical vapor deposition (CVD) and initiated CVD, enable the deposition of conformal polymer thin films to benefit a diverse array of applications. This short review for nanotechnologists, including those new to vapor deposition methods, covers the basic theory in designing a conformal polymer film vapor deposition, sample preparation and imaging techniques to assess film conformality, and several applications that have benefited from vapor deposited, conformal polymer thin films.

Lyotropic Liquid Crystalline Mesophase Governs Interfacial Molecular Orientation of Conjugated Polymer Thin Films

2020 ◽  
Vol 32 (14) ◽  
pp. 6043-6054
Author(s):  
Ge Qu ◽  
Kyung Sun Park ◽  
Prapti Kafle ◽  
Fengjiao Zhang ◽  
Justin J. Kwok ◽  
...  
Keyword(s):  
Thin Films ◽  
Conjugated Polymer ◽  
Molecular Orientation ◽  
Liquid Crystalline ◽  
Polymer Thin Films
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