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Tribologiczne właściwości triazynowych materiałów kompozytowych

Mizerski M., Cielichowski G., Kolesińska J.

Tribologia

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2004

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nr 5

195-203

PL

W prezentowanym materiale zostały przedstawione wyniki badań mikro- i nanotribologicznych materiałów nanokomppozytowych otrzymanych w wyniku chemicznej modyfikacji powierzchni cienkich warstw amino-krzemionki na podłożu krzemowym za pomocą alkoksy- i aryloksy- pochodnych 1,3,5-triazyny. Prawidłowy przebieg syntezy tych materiałów kontrolowano metodami spektroskopii IR, a także SIMS. Tak wytworzone nieorganiczno-organiczne nanokompozyty hybrydowe charakteryzują się dobrymi własnościami tarciowymi w mikro- i nanoskali, co zostało zbadane z użyciem mikrotribometru, a także mikroskopu sił atomowych z pomiarem siły tarcia (FFM/LFM). Otrzymane rezultaty wskazały na znaczące obniżenie wartości współczynnika tarcia w stosunku do wyjściowego materiału. Generalny wniosek jest taki, iż w większości przypadków alkiloksytriazyny są lepszymi modyfikatorami powierzchni niż aryloksytriazyny. Stwierdzono także, iż modyfikacja pochodnymi triazynowymi, pozwalająca na wprowadzenie na powierzchnię długiego łańcucha węglowego, także fluorowego, daje najlepsze rezultaty.

EN

A series of composite materials based on alkoxy- or aryloxy- triazines and aminosilica, which was prepared by sol-gel method from 3-aminopropyltriethoxysilane and coated on silicon as thin film, were investigated. The effects of modification was confirmed by FT-IR spectroscopy and Secondary Ion Mass Spectrometry (SIMS). In this work was presented fusion of good features of aminosilica and triazines to obtain inorganic/organic hybrids which should present good frictional properties, significantly better than pure silica material. The microtribological tests were carried out on tribometer ball-on sample system. The friction force was measured and calculated to friction coefficient. The results showed that triazine composite materials significantly improved the frictional properties. When the triazine derivatives included long carbon chains (C8T, FCDMT) the friction coefficient decreased most in comparison to non-modified materials (APTS). The same effect were observed at nanoscale by AFM-studies. It also confirmed that in the most cases alkoxy- triazines were better modifiers than aryloxy- triazine derivatives apart from triazine derivatives included non-substituted position in triazine ring (mCF3T).

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Application of DSC and TG techniques for investigations of triazines thermal degradation

Drożdżewska K., Książczak A.

Polish Journal of Applied Chemistry

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2003

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Vol. 47, nr 3

191-201

EN

The vapour pressure of liquid substances causes difficulties and even in some cases makes the reliable interpretation of DSC and TG results in stability determinations impossibile. The efforts were made towards the reduction of evaporation process in decomposition by choice of proper measurement conditions. Triazines containing the -Cl, -OCH3 and -SCH3 substituents were chosen as the model compounds for the measurement methodology. They are mainly used as a herbicides. They are in liquids state during the thermal decomposition measurements The most advantageous conditions for high temperature chemical change detection through thermogravimetry measurements were reached with application of platinum labyrinth crucibles with constant mass loss rate Q=0,1 mg/min and boundary heating rate of 5K/min. In the case of DSC method, the most reliable results were obtained for measurements performed in hermetical alumina pans closed under vacuum. The sample pans with small lid holes of j=0.05 mm were used for determination of catalytic properties of volatile decomposition products.

PL

W pracy omówiono zastosowanie dwóch technik analizy termicznej takich jak różnicowa kalorymetria przemiatająca (DSC) i termograwimetria (TG) do badania przemian termicznych triazyn. Jako związki modelowe wybrano kilka triazyn, które znajdują zastosowanie jako herbicydy. Stwierdzono, że szczególną rolę w ustalaniu metodyki pomiarów odgrywa rodzaj i typ naczyniek stosowanych w tych metodach. W zależności od tego, czy stosuje się naczyńka bez pokrywki czy labiryntowe, obserwuje się różne przebiegi procesów. Zastosowanie naczyniek ze swobodnym lub utrudnionym odpływem fazy gazowej prowadzi do różnych warunków i temperatur zachodzących przemian chemicznych spowodowanych działaniem temperatury.

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Dinuclear polypyridine complexes of 2,4,6-tris(2-pyridyl)-1,3,5-triazine: mixed ligand Ni(II), Co(II) and Cu(II) complexes containing dithiooxamide and thiosemicarbazide

Ibrahim S. A., Hammam A. M., El-Gahami M. A., Fouad D. M.

Bulletin of the Polish Academy of Sciences. Chemistry

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2003

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Vol. 51, No. 2

93-103

EN

A series of novel dinuclear mixed-ligand complexes having the general formula [M(2)(tpt)(L)(4]Cl(4)nH(2)O where M = Ni(II), Co(II) or Cu(II); tpt = 2,4,6-tris(2-pyridyl)-l,3,5-triazine; L = dithiooxamide (dto) or thiosemicarbazide (tsc); n = 2 — 4, have been synthesized and characterized. The tpt molecule is flexidentate, where it can behave as di- or tridentate and either mono- or dinucleating ligand. The coordination mode of the tpt to the M(II) apparently occurs through pyridyl and a triazine nitrogen atoms. The binary complexes have the formulas [Co(2)(tpt)Cl4H(2)O].2H(2)O, [Ni(tpt)Cl]Cl.5.5H(2)O and [Cu(tpt)Cl(2)].3H(2)O. All the mixed-ligand complexes are dinuclear with bridging tpt molecule and having an octahedral structure. Binary Co(II) and Cu(II) complexes are probably penta coordinated. The complexes under study were characterized by chemical analysis, spectral, molar conductance and thermal studies.

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Distribution of triazine-type herbicides in the surface waters of the southern Baltic

Pazdro K., Tronczyński J., Pempkowiak J.

Oceanologia

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1999

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No. 41 (2)

255-264

EN

Triazine-type herbicides (atrazine, simazine, terbuthylazine, DEA - deethylatrazine) were analysed in the surface waters of the Baltic Sea off Poland in September 1995 and April 1997. Total concentrations varied from 14.7 to 30.0 ng dm-3 in 1995 and from 8.5 to 12.7 ng dm-3 in 1997. Concentrations in offshore samples were much smaller than in inshore ones (15.6š2.2 vs 23.5š4.8) in 1995, while no differences were found in 1997 (9.2š1.8 vs 10.1š2.3). This was attributed to the increased input of triazines to the Baltic Sea with river run-off following the summer application of these substances in agriculture. The ratios of concentrations of individual compounds indicate that terbuthylazine is present in similar proportions in the Pomeranian Bay and the Gulf of Gdansk (21% vs 20%), despite the ban on the use of atrazine and simazine in Germany imposed in the early 1990s. Similar DEA-to-atrazine indices in both the Pomeranian Bay and the Gulf of Gdansk (1.20š0.22 vs1.31š0.25) support the inference that the run-off from the rivers Vistula and Odra contributes to the distribution of triazines in the surface waters of the southern Baltic.