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1

Heat resisting and water-soluble chocolate polyesters containing azomethine group

Temizkan K., Kaya I.

Materials Science Poland

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2017

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Vol. 35, No. 2

303--312

EN

In this study, soluble in water poly(azomethine-ester)s (PAEs) were synthesized via elimination reactions of aromatic dihydroxy compounds containing imine bonding with terephthaloyl chloride. The structures of Schiff bases (SBs) and PAEs containing different aliphatic chains were confirmed by FT-IR, 1H-NMR, 13H-NMR C-NMR and UV-Vis analyses. Physicochemical properties of the new polymers were characterized. Thermal properties of the compounds were investigated by TGA-DTA, DMA and DSC. According to TGA measurements, the starting degradation temperatures (Ton) of P-1, P-2, P-3, and P-4 poly(azomethine-ester)s were found as 255 °C, 232 °C, 222 °C, and 221 °C, respectively. The starting degradation temperatures of the poly(azomethine-ester)s were higher than their Schiff base compounds. According to dynamical mechanical analysis (DMA) measurements, glass transition temperature (Tg) of P-1, P-2, P-3, and P-4 poly(azomethine-ester)s were found as 95 °C, 138 °C, 140 °C, and 145 °C, respectively. The morphological and topographic properties of the PAEs containing azomethine linkage in the main chain were investigated by FE-SEM and AFM, respectively. The molecular mass distributions of PAEs were determined by gel permeation chromatography (GPC). Electrochemical (E′g) and optical band gap (Eoptg ) values of the prepared SBs and PAEs were calculated from cyclic voltammetry (CV) and UV-Vis analyses. The electrochemical band gap (E′g) values of P-1, P-2, P-3 and P-4 were found as 2.44 eV, 2.41 eV, 2.39 eV and 2.39 eV, respectively, from the cyclic voltammetry.

2

All-optical sensor based on nonlinear multimode interference coupler features

Tajaldini M, Jafri M Z M

Optica Applicata

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2015

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Vol. 45, nr 3

327--340

EN

In this study, we investigate the sensing applications in the presence of the nonlinear effects by proposing an all-optical sensor and considering nonlinear effects on modal propagation and output intensity based on an ultra-compact nonlinear multimode interference coupler. The sensor can be tuned to have the highest sensitivity in the wavelength and refractive index ranges and can detect water-soluble chemicals, air-pollutions, earthquake wave, blood parameters, and heart operation. The results indicate high output sensitivity to input wavelength whereas the nonlinear effects appear in the medium. This sensitivity led us to propose a wave sensor of both transverse and longitudinal waves, such as acoustic and light waves, when an external wave interacts with an input waveguide. For instance, this sensor can be implemented using a long input that is inserted in the land, and any wave could then be detected from the Earth. The visible changes in intensity at the output facet in various refractive indices of the surrounding layer show the high sensitivity to the refractive index of the surrounding layer, which is the foundation of introducing a sensor. Generally, the results show the high efficiency of nonlinear effects in all-optical sensing performances.

3

Biodegradable acrylic pressure-sensitive adhesives

Czech Z., Pełech R., Butwin A.

Czasopismo Techniczne. Chemia

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2008

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R. 105, z. 2-Ch

293-301

EN

Biodegradable water-soluble pressure-sensitive adhesives (PSA) based on acrylic are still something of a speciality. They are synthesized from typical acrylate monomers such as soft 2-ethylhexyl acrylate (2-EHA) or butyl acrylate (BA), hard monomers as methyl acrylate (MA) or ethyl acrylate (EA), hydroxylated acrylates as 2-hydroxyethyl- or 2-hydroxypropyl acrylate and vinyl carboxylic acid suitable for water solubility and crosslinking reaction, as acrylic acid (AA) or [beta]-acryloiloxypropionic acid (BCEA). After synthesis the water-soluble acrylic PSA are modified through addition of water-soluble plasticizers, water-soluble ethoxylated amines, and special soft or hard resins, and neutralized in the presence of potassium hydroxide. After this procedure the water-soluble acrylic PSA are crosslinked using different external crosslinking agents.

PL

Biodegradowalne rozpuszczalne w wodzie poliakrylanowe kleje samoprzylepne mają obecnie szerokie zastosowanie w wielu aplikacjach. Są one otrzymywane z typowych monomerów akrylanowych, takich jak: monomery obniżające temperaturę zeszklenia polimeru: akrylan 2-etyloheksylu (2-EHA) oraz akrylan butylu (BA) oraz monomery podwyższające kohezję, takie jak akrylan metylu (MA) lub akrylan etylu (EA), a także monomery funkcyjne, jak np. akrylan 2-hydroksyetylu, akrylan 2-hydroksypropylu oraz karboksylowe kwasy winylowe, jak np. kwas akrylowy (AA) lub kwas [beta]-akryloilooksypropionowy (BCEA). Po syntezie rozpuszczalne w wodzie akrylanowe (PSA) są modyfikowane przez dodatek wodorozcieńczalnych plastyfikatorów, etanoloamin, specyficznych żywic zmiękczających i utwardzających oraz związków neutralizujących (KOH). Zmodyfikowane są sieciowane przez zastosowanie odpowiednich czynników sieciujących.