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1

Polyurethane elastomers based on carbonic and tartaric acid derivatives as renewable resources

Rokicki G., Mazurek M., Tomczyk K.

Polimery

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2015

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T. 60, nr 9

541--550

EN

In the present study, three methods of introduction of the tartaric acid derivative into poly(carbonate-urethane)s chemical structure are presented and discussed. Tartaric acid derivative containing two free and two protected OH groups was introduced according to polycondensation, ring opening polymerization (in oligocarbonate synthesis step) and polyaddition (in prepolymer synthesis step as a chain extender) reactions. The prepared poly(carbonate-urethane)s were characterized by NMR and FT-IR spectroscopies, DSC and TGA thermal analyses, and mechanical properties measurements. The influence of the introduced tartaric acid derivative on properties of oligocarbonates and polyurethanes was investigated.

PL

Opisano trzy sposoby wbudowania do struktury poli(węglano-uretanów) pochodnej kwasu winowego, zawierającej dwie wolne i dwie zablokowane grupy OH, z wykorzystaniem polikondensacji, polimeryzacji z otwarciem pierścienia (na etapie syntezy oligowęglanodioli) i poliaddycji stopniowej (na etapie syntezy prepolimeru jako przedłużacza łańcucha). Otrzymane poli(węglano-uretany) scharakteryzowano metodami spektroskopii NMR i FT-IR, analizy termicznej DSC i TGA oraz za pomocą pomiarów wytrzymałości mechanicznej. Oceniono wpływ zawartości pochodnej kwasu winowego na właściwości oligowęglanów i poliuretanów.

2

Kwas winowy i jego pochodne we współczesnej chemii organicznej

Grajewski J.

Wiadomości Chemiczne

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2013

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[Z] 67, 5-6

495--519

EN

The tartaric acid and its salts have been present in chemistry for almost 350 years, since Pierre Seignette isolated Rochelle salt in 1675. Since that time tartaric acid and its derivatives have been often used in chemistry due to their accessibility, enantiopurity, relatively low cost and presence of different functional groups which easily allow to modify the molecule. Many tartaric acid derivatives serve as catalysts in important stereoselective transformations such as Sharpless asymmetric epoxidation or asymmetric Rousch aryloboronation. In many others reactions tartaric acid have been employed as a chiral building block for natural products synthesis, highly functionalized molecules or ligand design such as well known TADDOL or its analogues. Its polar functional groups allow to form crystals with amines and aminoalcohols what is widely used for their enantiopurification and resolution. The relatively new subdiscipline is the use of tartaric acid in chiral recognition and chiral discrimination in nanochemistry and enantioselective chromatography. The other, recent applications of tartaric acid include functionalization of metal layers, antibacterial and antifungal activity among many others. The significance of tartaric acid is evident – since 2000, words “tartaric acid” or “tartrates” can be found in databases over four thousand times. Taking that into account this short review is concentrated on selected applications of tartaric acid and its derivatives in organic chemistry in recent several years.

3

Characterization of nanocrystalline LiNi1-xCoxVO4 prepared by the polymerized complex method

Thongtem W. T., Phuruangrat A., Thongtem S.

Materials Science Poland

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2009

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Vol. 27, No. 1

43--49

EN

Nanocrystalline LiNi1-xCoxVO4 (x = 0.00, 0.25, 0.50, 0.75 and 1.00) was prepared from Li2CO3, Ni(NO3)2.6H2O, Co(NO3)2.6H2O and NH4VO3, using tartaric acid as a complexing agent, followed by 450 °C calcination for 12 h. TGA results show that nanocrystallites started to form at 450-550 °C. Inverse spinel LiNi1-xCoxVO4 was detected using the XRD and SAED methods. The calculated lattice parameter increased upon increasing Co concentration. It was in accordance with the increase in the particle size determined using TEM images. A stretching band of VO4 tetrahedra was detected at 651-820 cm-1 using FTIR. V-O vibrational bands analyzed with a Raman spectrometer were shifted to the lower wavenumbers, due to the increase of Co concentration. The selected elements were also analyzed using EDX and AAS to determine the stoichiometric values (x) of the oxides.

4

Tartaronitriles – the Derivatives of Tartaric Acid with a Bent Conformation

Gawroński J., Gawrońska K., Waścinska N., Plutecka A., Rychlewska U.

Polish Journal of Chemistry

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2007

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Vol. 81, nr 11

1917-1925

EN

Conformational preferences of dinitrile derivatives of (R,R)-tartaric acid were studied by means of NMR, CD and X-ray diffraction techniques. Where as other derivatives of (R,R)-tartaric acid exist predom i nantly in an extended (T) or bent (G–) conformation, (R,R)-tartarodinitriles show pronounced tendency to ward bent G+ conformation. This is rationalized by the presence of the “gauche effect” in volving maximum number of stabilizing in teractions between the polar groups within the tartarodinitrile molecule.

5

Kompleksowanie jonów żelaza(III) kwasem d,1-winowym w środowisku kwaśnym

Bukowski W.

Zeszyty Naukowe Politechniki Rzeszowskiej. Chemia

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1999

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z. 16 [173]

57-65

PL

Metodą spektrofotometryczną przebadano kompleksowanie jonów żelaza(III) kwasem d,1-winowym (H2T) w środowisku kwaśnym (pH = 1,2). Metodą Asmusa ustalono tworzenie się dwóch monomerycznych kompleksów o składzie Fe3+ : H2T równym 1:1. Obliczono stałe równowagi tworzenia tych kompleksów oraz ich stałe trwałości.

EN

Complexes of iron(III) ions with d,1-tartaric acid (H2T) in acidic medium (pH = 1,2) were studied by UV -VIS spectrometry. The formation of two monomeric complexes with the ratio Fe3+ : H2T equal 1:1 has been established by using the Asmus method. The equilibrium and stability constants of the complexes have been calculated.