scholarly journals Synthesis and Properties of Poly(imides) and Poly(imides)/Ionic Liquid Composites Bearing a Benzimidazole Moiety

Polymers ◽  
2019 ◽  
Vol 11 (5) ◽  
pp. 759
Author(s):  
Terraza ◽  
Ortiz ◽  
Tagle ◽  
Pérez ◽  
Saldias ◽  
...  
Keyword(s):  
Contact Angle ◽  
Ionic Liquid ◽  
Composite Films ◽  
Oxidative Degradation ◽  
Spectroscopic Techniques ◽  
Conductivity Measurements ◽  
Oxidative Stabilization ◽  
Flexible Spacer ◽  
Flexible Films ◽  
Poly Imide

Three new aromatic poly(imides) containing benzimidazole units in the backbone were synthesized and characterized by several spectroscopic techniques. Flexible spacer groups were incorporated into the poly(imides) structure to improve their solubility in organic solvents and their oxidative stabilization. All poly(imides) were thermally stable (Td5% > 512 °C) and had the ability to form dense flexible films. Novel composite films were successfully prepared by loading poly(imide) with ionic liquid ([Bmim]Br) at different concentrations up to 25 wt.%. The resulting materials were characterized according to their morphology and elemental composition (SEM-EDX), water uptake capability, contact angle, and oxidative degradation resistance. Results suggested that poly(imide)/ionic liquid composites would be excellent candidates for future proton conductivity measurements.

Expanded vermiculite-filled flexible polymer composites

2021 ◽  
pp. 009524432110290
Author(s):  
Mukaddes Sevval Cetin ◽  
Ozan Toprakci ◽  
Omer Suat Taskin ◽  
Abdullah Aksu ◽  
Hatice Aylin Karahan Toprakci
Keyword(s):  
Mechanical Properties ◽  
Thermal Stability ◽  
Contact Angle ◽  
Polymer Composites ◽  
Flame Retardancy ◽  
Composite Films ◽  
Filler Concentration ◽  
High Shear ◽  
Flexible Polymer ◽  
Shear Mixing

This study focuses on the fabrication and characterization of vermiculite-filled flexible polymer composites. Exfoliated vermiculite was incorporated into triblock thermoplastic elastomer copolymer, styrene- b-(ethylene- co-butylene)- b-styrene (SEBS), at various levels from 1 to 15 wt% by a high shear mixer. The composite films were obtained by the combination of solvent casting and compression molding. The morphological, structural, thermal, and mechanical properties and contact angle of the composites were determined. Some micro-morphological differences were observed between the samples and the difference was assumed to be caused by high shear mixing and filler concentration. High shear mixing was found effective in terms of the detachment of vermiculite layers at all concentrations. However, at low filler loading, that behavior was more obvious. At 1 wt% filler concentration, mechanical properties increased that was probably caused by good filler-matrix interaction stemmed from smaller particle size. At higher vermiculite concentrations, fillers found to show agglomerations that led to a decrease in mechanical strength and strain at break. Elastic and secant modulus showed an increasing trend. Contact angle measurements were carried out to determine the oleophilic character of the samples. An increase in the vermiculite content resulted in higher oleophilic character and the lowest contact angle was obtained at 15 wt% VMT loading. In addition to these, thermal stability, thermal dimensional stability and flame retardancy were improved by the incorporation of VMT. 15 wt% vermiculite-filled sample showed the best performance in terms of thermal stability and flame retardancy.

scholarly journals Ecofriendly Preparation and Characterization of a Cassava Starch/Polybutylene Adipate Terephthalate Film

Processes ◽  
2020 ◽  
Vol 8 (3) ◽  
pp. 329
Author(s):  
Tan Yi ◽  
Minghui Qi ◽  
Qi Mo ◽  
Lijie Huang ◽  
Hanyu Zhao ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Contact Angle ◽  
Water Vapor ◽  
Composite Film ◽  
Water Absorption ◽  
Composite Films ◽  
Thermoplastic Starch ◽  
Light Transmittance ◽  
Infrared Spectrometry ◽  
Nano Zno

Composite films of polybutylene adipate terephthalate (PBAT) were prepared by adding thermoplastic starch (TPS) (TPS/PBAT) and nano-zinc oxide (nano-ZnO) (TPS/PBAT/nano-ZnO). The changes of surface morphology, thermal properties, crystal types and functional groups of starch during plasticization were analyzed by scanning electron microscopy, synchronous thermal analysis, X-ray diffraction, infrared spectrometry, mechanical property tests, and contact Angle and transmittance tests. The relationship between the addition of TPS and the tensile strength, transmittance, contact angle, water absorption, and water vapor barrier of the composite film, and the influence of nano-ZnO on the mechanical properties and contact angle of the 10% TPS/PBAT composite film. Experimental results show that, after plasticizing, the crystalline form of starch changed from A-type to V-type, the functional group changed and the lipophilicity increased; the increase of TPS content, the light transmittance and mechanical properties of the composite membrane decreased, while the water vapor transmittance and water absorption increased. The mechanical properties of the composite can be significantly improved by adding nano-ZnO at a lower concentration (optimum content is 1 wt%).

Preparation of Cellulose/Xanthan Gum Composite Films and Hydrogels Using Ionic Liquid

2014 ◽  
Vol 22 (3) ◽  
pp. 298-303 ◽  
Author(s):  
Miwa Setoyama ◽  
Kazuya Yamamoto ◽  
Jun-ichi Kadokawa
Keyword(s):  
Ionic Liquid ◽  
Xanthan Gum ◽  
Composite Films

Effect of temperature on composite films made with activated carbon, graphite, or graphene oxide (GO) in a gelatin matrix

BioResources ◽  
2020 ◽  
Vol 16 (1) ◽  
pp. 77-95
Author(s):  
Siqiao Yang ◽  
Haichao Li
Keyword(s):  
Contact Angle ◽  
Activated Carbon ◽  
Water Absorption ◽  
Composite Films ◽  
Effect Of Temperature ◽  
Gelatin Matrix ◽  
Vapour Permeability ◽  
Blending Method ◽  
The Matrix ◽  
Different Temperatures

Activated carbon, graphite, and GO/gelatin composite films were prepared by the blending method. The properties of composites were characterized by tensile strength (TS), elongation at break (EB), water vapour permeability (WVP), water-absorption ability, contact angle, scanning electron microscopy (SEM), and moisture at different temperatures. The properties of GO/gelatin composite films were better when each of three kinds of carbon materials were used as reinforcement phases and added into the matrix gelatin. The results showed that EB and TS of GO/gelatin composite films were both excellent. The moisture of GO/gelatin composite films was greater than the others. SEM micrographs showed that GO had better compatibility and dispersibility with gelatin than activated carbon and graphite. The water absorption of GO/gelatin composite films were low, at 15 °C and 25 °C, and the WVP was low at 35 °C. The WVP of GO/gelatin composite films was lower than the others at different temperatures. The contact angle of GO/gelatin composite films was larger than the others.

scholarly journals Thermochromism of Highly Luminescent Photopolymer Flexible Films Based On Eu (III) Salts Confined in Polysulfone

Materials ◽  
2020 ◽  
Vol 13 (23) ◽  
pp. 5394
Author(s):  
Mani Outis ◽  
João Paulo Leal ◽  
Maria Helena Casimiro ◽  
Bernardo Monteiro ◽  
Cláudia Cristina Lage Pereira
Keyword(s):  
Thermal Stability ◽  
Ionic Liquid ◽  
Melting Point ◽  
Quantum Yield ◽  
Thermal Behavior ◽  
Temperature Dependence ◽  
Strong Temperature Dependence ◽  
Host Matrix ◽  
Flexible Films ◽  
First Time

Here we discuss the influence of two different cations on the emissive properties of the highly emissive [Eu(fod)4]− anion. The studied Eu(III) salts were [C16Pyr][Eu(fod)4] (1), and the previously reported [Chol][Eu(fod)4]. C16Pyr stands for N-cetylpyridinium, Chol for cholinium and fod for 1,1,1,2,2,3,3-heptafluoro-7,7-dimethyloctane-4,6-dionate. 1 is classified as ionic liquid, with melting point close to 60 °C, and presented a luminescence quantum yield of (ϕ) 100%. Ultrabright emissive photopolymers were obtained for the first time using polysulfone as the host matrix. The films were prepared with incorporation of 10% (w/w) of 1 and [Chol][Eu(fod)4] in the polymeric matrix, which improved its thermal stability. Additionally, the luminescence of CholEu(fod)4/PSU presented a strong temperature dependence with a ratiometric thermal behavior.

scholarly journals Synthesis, Crystal Structures, and Spectroscopic Characterization of Bis-aldehyde Monomers and Their Electrically Conductive Pristine Polyazomethines

Polymers ◽  
2019 ◽  
Vol 11 (9) ◽  
pp. 1498 ◽  
Author(s):  
Abdul Hafeez ◽  
Zareen Akhter ◽  
John F. Gallagher ◽  
Nawazish Ali Khan ◽  
Asghari Gul ◽  
...  
Keyword(s):  
Electrical Conductivity ◽  
Spectroscopic Characterization ◽  
Spectroscopic Techniques ◽  
Conductivity Measurements ◽  
X Ray Diffraction ◽  
Electrically Conductive ◽  
X Ray ◽  
Vis Spectroscopy ◽  
Ft Ir

Bis-aldehyde monomers 4-(4′-formyl-phenoxy)benzaldehyde (3a), 3-methoxy-4-(4′-formyl-phenoxy)benzaldehyde (3b), and 3-ethoxy-4-(4′-formyl-phenoxy)benzaldehyde (3c) were synthesized by etherification of 4-fluorobenzaldehyde (1) with 4-hydroxybenzaldehyde (2a), 3-methoxy-4-hydroxybenzaldehyde (2b), and 3-ethoxy-4-hydroxybenzaldehyde (2c), respectively. Each monomer was polymerized with p-phenylenediamine and 4,4′-diaminodiphenyl ether to yield six poly(azomethine)s. Single crystal X-ray diffraction structures of 3b and 3c were determined. The structural characterization of the monomers and poly(azomethine)s was performed by FT-IR and NMR spectroscopic techniques and elemental analysis. Physicochemical properties of polymers were investigated by powder X-ray diffraction, thermogravimetric analysis (TGA), viscometry, UV–vis, spectroscopy and photoluminescence. These polymers were subjected to electrical conductivity measurements by the four-probe method, and their conductivities were found to be in the range 4.0 × 10−5 to 6.4 × 10−5 Scm−1, which was significantly higher than the values reported so far.

scholarly journals Synthesis of the symmetrical methylene diesters from carboxylic ionic liquids

2017 ◽  
Vol 95 (7) ◽  
pp. 744-750 ◽  
Author(s):  
D. Gómora-Herrera ◽  
I.V. Lijanova ◽  
O. Olivares-Xometl ◽  
A. Toscano ◽  
N.V. Likhanova
Keyword(s):  
Ionic Liquid ◽  
Hydrogen Bonding ◽  
Ionic Liquids ◽  
Hydrogen Atom ◽  
Crystal Packing ◽  
Spectroscopic Techniques ◽  
Amine Group ◽  
Carboxylic Group ◽  
Microwave Reactor ◽  
Trimer Formation

The reaction between carboxylic ionic liquids and dichloromethane, which provokes the formation of symmetrical methylene diesters, was carried out. The synthesis of these ionic liquid compounds was carried out in a microwave reactor, and the characterization by spectroscopic techniques of methylene diesters (methylene di-2-furoate, methylene di-2-picolinate, methylene dianthranilate, and methylene dioleate) is described and the crystal structures discussed. The crystal packing of methylene dianthranilate is characterized by trimer formation due to hydrogen bonding via interactions between the hydrogen atom of the primary amine group and the oxygen of the carboxylic group.

Structure and Properties of Composite Films of Cellulose and Chitosan from Ionic Liquid

2012 ◽  
Vol 499 ◽  
pp. 80-84
Author(s):  
Huai Fang Wang ◽  
Wei Han Huang ◽  
Zhi Kai Wang
Keyword(s):  
Mechanical Properties ◽  
Thermal Stability ◽  
Ionic Liquid ◽  
Antimicrobial Property ◽  
Composite Films ◽  
Antibacterial Properties ◽  
Strong Interactions ◽  
Structure And Properties ◽  
Blend Films ◽  
Methyl Imidazole

A series of blend films of cellulose and chitosan were prepared from 1-ethyl-3-methyl imidazole acetate ([Emim] Ac) by coagulating with ethanol. Structure, mechanical properties, thermal stability and antibacterial properties were investigated. The results showed that there were strong interactions and good compatibility between cellulose and chitosan in blend films. The blend films possess good mechanical properties and thermal stability, and the existence of chitosan endows blend films with antimicrobial property.

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