scholarly journals Preparation of Soluble POSS-Linking Polyamide and Its Application in Antifogging Films

Materials ◽  
2021 ◽  
Vol 14 (12) ◽  
pp. 3178
Author(s):  
Tomoya Kozuma ◽  
Aki Mihata ◽  
Yoshiro Kaneko
Keyword(s):  
Water Vapor ◽  
Heat Treating ◽  
Scratch Test ◽  
29Si Nmr ◽  
Polar Solvents ◽  
Amide Bonds ◽  
Ethylcarbodiimide Hydrochloride ◽  
Ft Ir ◽  
Oligomeric Silsesquioxane ◽  
Condensing Agents

In this study, we prepared a polyhedral oligomeric silsesquioxane (POSS)-linking polyamide (POSS polyamide) by a polycondensation of ammonium-functionalized POSS (POSS-A) and carboxyl-functionalized POSS (POSS-C) in dehydrated dimethyl sulfoxide (DMSO) using 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDC) and N-hydroxysuccinimide (NHS) as condensing agents. The obtained POSS polyamide was soluble in various highly polar solvents, and it could form a self-standing film. FT-IR, 1H NMR, and 29Si NMR analyses showed that POSS polyamide is a polymer in which POSS-A and POSS-C are linked almost linearly by amide bonds. Furthermore, the cast film obtained by heat-treating the polymer at 150 °C for 30 min exhibited excellent transparency and hard-coating (pencil scratch test: 5H) and antifogging properties (evaluation by water vapor exposure).

scholarly journals A Selenone-Functionalized Polyhedral Oligomeric Silsesquioxane for Selective Detection and Adsorption of Hg2+ ions in Aqueous Solutions

Polymers ◽  
2019 ◽  
Vol 11 (12) ◽  
pp. 2084 ◽  
Author(s):  
Hailong Liu ◽  
Zixu Chen ◽  
Shengyu Feng ◽  
Dengxu Wang ◽  
Hongzhi Liu
Keyword(s):  
Aqueous Solutions ◽  
Acid Treatment ◽  
Color Change ◽  
Limit Of Detection ◽  
Polyhedral Oligomeric Silsesquioxane ◽  
Functional Materials ◽  
29Si Nmr ◽  
Highly Sensitive ◽  
Ft Ir ◽  
Oligomeric Silsesquioxane

Developing novel functional polyhedral oligomeric silsesquioxane (POSS) for various applications is highly desirable. Herein we present the first example of a novel selenone-functionalized POSS (POSS-Se) by treating an imidazolium-containing POSS with selenium powder under mild condition. The structure of POSS-Se was characterized by FT-IR, 1H NMR, 13C NMR, 29Si NMR, and elemental analysis. Acid treatment of POSS-Se results in a hydrophilic red-orange colored solid, which is highly sensitive and selective for the detection of Hg2+ ions in aqueous solutions by visually observing the color change to pale yellow, and to white. Interestingly, POSS-Se has no activity on this detection. This finding is due to the Se–Se formation by acid-treatment and subsequent coordination-induced cleavage upon the addition of Hg2+ ions. The detection behavior can be precisely monitored by a “turn-on” fluorescence phenomenon with the limit of detection (LOD) of 8.48 ppb, comparable to or higher than many reported Hg2+ sensors. Moreover, POSS-Se demonstrates a selective and efficient adsorption of Hg2+ ions with a maximum capacity of 952 mg g–1. The value is higher than most reported adsorbents for Hg2+ ions, typically thiol and/or thioether functional materials, indicating its promise as an efficient adsorbent for the selective removal of Hg2+ ions from industrial wastewater. This work may open up new horizons for the exploration of selenium-containing functional POSS.

Liquid crystalline polyureas with oligo(ethylene glycol) sequences

e-Polymers ◽  
2010 ◽  
Vol 10 (1) ◽  
Author(s):  
Shahram Mehdipour-Ataei ◽  
Leila Akbarian-Feizi
Keyword(s):  
Liquid Crystalline ◽  
Spectroscopic Method ◽  
Polymerization Reaction ◽  
X Ray Diffraction ◽  
Subsequent Reaction ◽  
Scanning Calorimetry ◽  
Polar Solvents ◽  
X Ray ◽  
H Nmr ◽  
Ft Ir

AbstractA diamine monomer containing ester, amide and ether functional groups was prepared and its polymerization reaction with different diisocyanates to give main chain poly(ester amide ether urea)s was investigated. The monomer was synthesized via reaction of terephthaloyl chloride with 4-hydroxybenzoic acid and subsequent reaction of the resulted diacid with 1,8-diamino-3,6-dioxaoctane. The polymers were characterized by FT-IR and 1H-NMR spectroscopic method and elemental analysis. The resulting polymers exhibited excellent solubility in polar solvents. Crystallinity of the resulted polymers was evaluated by wide-angle X-ray diffraction (WXRD) method, and they exhibited semi-crystalline patterns. The glass transition temperatures (Tg) of the polymers determined by differential scanning calorimetry (DSC) and dynamic mechanical thermal analysis (DMTA) were in the range of 88-112 °C. The temperatures for 10% weight loss (T10) from their thermogravimetric analysis (TGA) curves were found to be in the range of 297-312 °C in air. Also the prepared polyureas showed liquid crystalline character.

scholarly journals Preparation and characterization of polyhedral oligomeric silsesquioxane/polystyrene nanocomposites

e-Polymers ◽  
2012 ◽  
Vol 12 (1) ◽  
Author(s):  
Benhong Yang ◽  
Meng Li ◽  
Yun Wu ◽  
Kang Wang
Keyword(s):  
Thermal Stability ◽  
Thermal Property ◽  
Polyhedral Oligomeric Silsesquioxane ◽  
29Si Nmr ◽  
Solution Blending ◽  
Oligomeric Silsesquioxane ◽  
Tga And Dsc ◽  
Thermal Stability Of

AbstractSeveral inorganic/organic nanocomposites were prepared via solution-blending of cage-like octahexyl-polyhedral oligomeric silsesquioxane (Oh-POSS) with polystyrene (PS) in THF solvent. FTIR and 29Si-NMR were employed to characterize the structures of the nanocomposites. SEM pictures showed that the sample films were smooth and no POSS aggregation was observed when POSS content was lower than 1.0 wt%. TGA and DSC were used to investigate the thermal property. The results showed that the incorporation of nanosized Oh-POSS enhanced the thermal stability of PS with low POSS content. When 1.0 wt% of Oh-POSS was incorporated into PS matrix, the Tg and Td increased by 7.7 °C and 8.2 °C, respectively. However, higher POSS contents (>1.0 wt%) would deteriorate the thermal property of the nanocomposites due to the severe congregation of POSS..

FT-IR and 29Si-NMR for evaluating aluminium–silicate precursors for geopolymers

2014 ◽  
Vol 48 (3) ◽  
pp. 557-569 ◽  
Author(s):  
Siska L. A. Valcke ◽  
Panagiota Pipilikaki ◽  
Hartmut R. Fischer ◽  
Margriet H. W. Verkuijlen ◽  
Ernst R. H. van Eck
Keyword(s):  
29Si Nmr ◽  
Ft Ir ◽  
Aluminium Silicate

Preparation and Characterization of Corn Starch-Nanodiamond Composite Films

2013 ◽  
Vol 469 ◽  
pp. 156-161 ◽  
Author(s):  
Hong Pan ◽  
Dan Xu ◽  
Qin Liu ◽  
Hui Qing Ren ◽  
Min Zhou
Keyword(s):  
Water Vapor ◽  
Food Packaging ◽  
Corn Starch ◽  
Composite Films ◽  
Water Vapor Permeability ◽  
Nanocomposite Films ◽  
Vapor Permeability ◽  
Ft Ir ◽  
Loading Amount ◽  
Physical Blending

Starch-based nanocomposite films were fabricated by the incorporation of different amounts of nanodiamond (ND) particles. These films were characterized by SEM, FT-IR, TGA, tensile testing and water vapor permeability measurement. It was observed that at low loadings, ND dispersed well in starch matrix. However, as the loading amount increased, aggregates as large as several micrometers appeared. The physical blending of ND with starch didnt change the thermal degradation mechanisms of starch films, only increased the char residues. As the ND loading increased, the tensile strength of composite films increased but the elongation at break decreased. However, the water vapor permeability increased as the loading of ND increased due to the increased microspores in films. With further modifications, ND may be considered as a novel of biocompatible nanofillers for reinforcement of biopolymers for food packaging applications.

Synthesis and characterization of O- and S-bridged perfluoroalkylated metal-free and zinc phthalocyanines

2013 ◽  
Vol 17 (06n07) ◽  
pp. 555-563 ◽  
Author(s):  
İlke Gürol ◽  
Gülay Gümüş ◽  
Emel Musluoğlu ◽  
Yadigar Arslan ◽  
Vefa Ahsen
Keyword(s):  
Nucleophilic Substitution ◽  
Elemental Analysis ◽  
Synthesis And Characterization ◽  
Polar Solvents ◽  
Metal Free ◽  
Zinc Phthalocyanines ◽  
Ft Ir

The synthesis of tetra and octa perfluoroalkyl substituted zinc and metal free phthalocyanines ( ZnPc and H 2 Pc ) are reported. The compounds 1–5 have been prepared by nucleophilic substitution of 4-nitrophthalonitrile with 1H,1H,2H,2H-perfluorooctanethiol, 1H,1H,2H,2H-perfluorodecan-1-ol, 1H,1H-perfluorodecan-1-ol, 1H,1H-perfluorotetradecan-1-ol and 1H,1H-perfluoro-3,6,9-trioxatridecan-1-ol, respectively. The compounds 6–8 have been prepared by the reaction of 1H,1H,2H,2H-perfluorodecan-1-ol, 1H,1H-perfluorodecan-1-ol and 1H,1H-perfluoro-3,6,9-trioxatridecan-1-ol with 4,5-dichlororphthalonitrile, respectively. The compound 9 with thia-bridge has been synthesized from 4,5-dichlororphthalonitrile. Zinc and metal free phthalocyanines were obtained from the corresponding phthalonitrile derivatives. All compounds were characterized by using mass, 1 H , 19 F NMR, UV-vis and FT-IR as well as elemental analysis. Tetra substituted Zn ( II ) phthalocyanines are slightly soluble only in THF (Compound 4a and 7a are insoluble) but metal free phthalocyanines are not soluble. Octa substituted Zn ( II ) and metal free phthalocyanine are soluble in polar solvents such as THF and DMSO.

Effects of Solvent Polarity on the Urethane Reaction of 1,2-Propanediol

2012 ◽  
Vol 450-451 ◽  
pp. 38-41
Author(s):  
Peng Fei Yang
Keyword(s):  
Rate Constant ◽  
Solvent Polarity ◽  
Reaction Rates ◽  
Phenyl Isocyanate ◽  
Second Order Reaction ◽  
Polar Solvents ◽  
Initial Stage ◽  
Ft Ir ◽  
Kinetics Of

The urethane reaction kinetics of 1,2-propanediol with phenyl isocyanate are investigated in different solvents, such as xylene, toluene and dimethylformamide. In-situ FT-IR is used to monitor the reaction to work out rate constant. It showsthat the urethane reaction has been found to be a second order reaction, solvents largely affects reaction rates. The reaction is largely accelerated in polar solvents, following the order of dimethylformamide > toluene > xylene. Further more, when dimethylformamide is used as solvent, the rate constants are different between initial stage and final stage, which belongs to different hydroxyls in 1,2-propanediol. However, when toluene or xylene is used as solvent, the rate constant is the same. That is, there is no reactivity difference for hydroxyls in 1,2-propanediol.

scholarly journals Extraction and Determination of Nicotine in Tobacco from Selected Local Cigarettes Brands in Iraq

2021 ◽  
Vol 11 (1) ◽  
pp. 3278-3290
Keyword(s):  
Alkaline Solution ◽  
Mercuric Chloride ◽  
Tobacco Plant ◽  
Health Hazard ◽  
Spectrometric Analysis ◽  
Polar Solvents ◽  
Tobacco Leaves ◽  
Tobacco Production ◽  
Ft Ir ◽  
Potential Risks

Tobacco smoke contains more than 3,800 different compounds, where all could harm the exposed humans to different degrees. Among them, nicotine (3-(1-methyl-2-pyrrolidinyl) pyridine) is considered the most toxic compound. In many countries, tobacco smoking is considered a severe health hazard and a significant factor in death and several common diseases. Because of that, knowing the toxicity of nicotine is important to help understand tobacco-induced human diseases and identify the potential risks associated with the therapeutic use of nicotine as an aid in smoking cessation. Thereby, estimating the nicotine amount is very crucial in tobacco production. As this work aims to extract and determine nicotine, which is the highest toxic component in tobacco plant leaves, several methods were carried out to extract the nicotine. All extracting methods were based on water extraction as a polar solvent and the other non-polar solvents. Water shows a limited extraction activity for nicotine from tobacco leaves. Since nicotine is a dibasic compound, an alkaline solution (40% NaOH) was used to extract nicotine from tobacco leaves for the selected samples. Further, solvent extraction by non-polar solvents was conducted to extract nicotine from the alkaline solution and prepare it for the spectrometric analysis. FT-IR and UV analysis show that the oily substance, which was extracted from tobacco leaves, is nicotine. Results were confirmed by microscopic examination for the extracted nicotine after the addition of mercuric chloride, where flowery shape crystals of nicotine liganded with mercuric chloride complex were formed.

scholarly journals Tailored Crosslinking Process and Protective Efficiency of Epoxy Coatings Containing Glycidyl-POSS

Polymers ◽  
2020 ◽  
Vol 12 (3) ◽  
pp. 591 ◽  
Author(s):  
Mirjana Rodošek ◽  
Mohor Mihelčič ◽  
Marija Čolović ◽  
Ervin Šest ◽  
Matic Šobak ◽  
...  
Keyword(s):  
Ring Opening ◽  
Protective Coatings ◽  
Diglycidyl Ether ◽  
Scanning Calorimetry ◽  
Protective Efficiency ◽  
Crosslinking Process ◽  
Operational Temperature ◽  
Epoxy Ring Opening ◽  
Ft Ir ◽  
Oligomeric Silsesquioxane

Versatile product protective coatings that deliver faster drying times and shorter minimum overcoat intervals that enable curing at faster line speeds and though lower energy consumption are often desired by coating manufacturers. Product protective coatings, based on silsesquioxane-modified diglycidyl ether of bisphenol-A (DGEBA) epoxy resin, are prepared through a glycidyl ring-opening polymerization using dicyandiamide (DICY) as a curing agent. As silsesquioxane modifier serves the octaglycidyl-polyhedral oligomeric silsesquioxane (GlyPOSS). To decrease the operational temperature of the curing processes, three different accelerators for crosslinking are tested, i.e., N,N-benzyl dimethylamine, 2-methylimidazole, and commercial Curezol 2MZ-A. Differential scanning calorimetry, temperature-dependent FT-IR spectroscopy, and rheology allow differentiation among accelerators’ effectiveness according to their structure. The former only contributed to epoxy ring-opening, while the latter two, besides participate in crosslinking. The surface roughness of the protective coatings on aluminum alloy substrate decreases when the accelerators are applied. The scanning electron microscopy (SEM) confirms that coatings with accelerators are more homogeneous. The protective efficiency is tested with a potentiodynamic polarization technique in 0.5 M NaCl electrolyte. All coatings containing GlyPOSS, either without or with accelerators, reveal superior protective efficiency compared to neat DGEBA/DICY coating.

scholarly journals Mechanical Properties, Microstructure, and Chloride Content of Alkali-Activated Fly Ash Paste Made with Sea Water

Materials ◽  
2020 ◽  
Vol 13 (6) ◽  
pp. 1467
Author(s):  
Salman Siddique ◽  
Jeong Gook Jang
Keyword(s):  
Compressive Strength ◽  
Fly Ash ◽  
Sea Water ◽  
Tap Water ◽  
Pure Water ◽  
Degree Of Polymerization ◽  
29Si Nmr ◽  
Water Based ◽  
Ft Ir ◽  
Alkali Activated

The aim of the present study is to investigate the potential of sea water as a feasible alternative to produce alkali-activated fly ash material. The alkali-activated fly ash binder was fabricated by employing conventional pure water, tap water, and sea water based alkali activating solution. The characteristics of alkali-activated materials were examined by employing compressive strength, mercury intrusion porosimetry, XRD, FT-IR, and 29Si NMR along with ion chromatography for chloride immobilization. The results provided new insights demonstrating that sea water can be effectively used to produce alkali activated fly ash material. The presence of chloride in sea water contributed to increase compressive strength, refine microstructure, and mineralogical characteristics. Furthermore, a higher degree of polymerization on the sea water-based sample was observed by FT-IR and 29Si NMR analysis. However, the higher amount of free chloride ion even after immobilization in sea water-based alkali-activated material, should be considered before application in reinforced structural elements.

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