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Barwniki polimetinowe jako sensybilizatory w układach fotoinicjujących polimeryzację wolnorodnikową monomerów wielofunkcyjnych

Kabatc J., Szynwelska E.

Prace Instytutu Elektrotechniki

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2010

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Z. 244

229-238

PL

W pracy opisano dwu- i trójskładnikowe układy fotoinicjujące, zawierające absorbujący światło barwnik cyjaninowy, donor elektronu (sól n-butylotrifenyloboranową) oraz trzeci składnik (sól N-alkoksypirydyniową, pochodną 1,3,5-triazyny, ester N-metylopikoliny, cykliczny acetal lub heteroaromatyczny merkaptan) jako bardzo efektywne inicjatory polimeryzacji wolnorodnikowej w zakresie światła widzialnego. Ustalono mechanizm reakcji zachodzących w trójskładnikowych układach fotoinicjujących. Otrzymany rodnik boranylowy ulega szybkiej dekompozycji, dając rodniki alkilowe, które inicjują proces polimeryzacji. Pierwotnym procesem fotochemicznym jest przeniesienie elektronu z anionu boranowego na barwnik w stanie wzbudzonym. Proces przeniesienia elektronu z rodnika barwnika cyjaninowego na drugi koinicjator, prowadzi do otrzymania kationu barwnika cyjaninowego oraz drugiego rodnika, który może zainicjować łańcuchową reakcję polimeryzacji.

EN

In this paper, the two- and three-component photoinitiating systems composed of cyanine dyes as a primary absorber of the light, electron donor (n-butyltriphenylborate salt) and third component (N-alkoxypyridinium salt, 1,3,5-triazyne derivative, N-methylpicolinium ester, cyclic acetal or heteroaromatic thiol) as very efficient photoinitiators of free radical polymerization in the visible light region. The mechanism of photochemical reactions occuring in the three-component photoinitiating systems after irradiation with visible light was proposed based on the results of laser flash photolysis. In these systems, the electron transfer from borane anion on the excited singlet state of cyanine dye is the primary photochemical process. The decomposition of boranyl radical leads to the generation of butyl radical which can start the polymerization chain reaction. In the next step, the electron transfer from cyanine dye radical on the third component occurs and second initiating radical is formed.

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Związki magnezu z ligandami aryloksanowymi : inicjatory polimeryzacji laktydów

Ejfler J.

Wiadomości Chemiczne

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2008

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[Z] 62, 9-10

875-899

EN

Magnesium alkoxides and aryloxides are systematically explored in various kinds of chemical processes and among other, their use as reagents in organic transformations [1-5], supports or catalyst components in polyolefin industry [6, 7], chemical precursors for advanced materials [8-10], as well as initiators for the polymerization of cyclic esters [11, 12] are worth mentioning. Over the past few years we have witnessed an increasing research on the use of magnesium aryloxides in the synthesis of new, biodegradable polymers, which have been preferential candidates for applications in medicine, pharmacy and production of eco-friendly bulk packing materials [13-15, 54-56]. Ready availability of monomers from inexpensive, renewable resources and the fact that resulted materials do not degrade the environment are an additional asset. Biodegradable polymers for the biomedical applications are preferably obtained using initiators containing non-toxic metals, and aryloxides of metals such as magnesium are especially interesting in this context. Despite the high utility limited number of magnesium alkoxides and aryloxides reported in the literature have a well-defined structure proved by X-ray analysis, which is required to design "single-site" catalysts. However, it is possible to identify and characterise certain types of frameworks. Homoleptic magnesium bis-aryloxides depending on synthesis procedures and ligand structure can crystallise as monomers [12, 40, 44], dimers [47, 48], trimers [47, 48] and tetramers [47, 48] with the coordination number ranging from three to six. Among them candidates of primary importance for the application in the ring-opening polymerization (ROP) of cyclic esters are monomeric compounds. Up to now, however, only few examples of such species displaying the certain activity in living polymerization have been published [60-63]. Extremely important are homoleptic compounds able to act as initiators for ROP in presence of exterior alcohols which form end-groups in the resulting polymer [12, 50]. This constitutes a chance for the polymer chain modyfication achieved by simple introduction of functional groups and enable to obtain new drug-polymer complex.

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Wpływ inicjatora niszczenia na wartość energii absorbowanej

Gieleta R., Niezgoda T., Ochelski S.

Prace Naukowe Politechniki Warszawskiej. Mechanika

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2007

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z. 219

89--102

PL

W pracy opisano wyniki badań wpływu inicjatora niszczenia, elementów energochłonnych zastosowanych na rdzenie konstrukcji przekładkowych, na zdolność pochłaniania energii uderzenia. Wykazano, że inicjatory zapewniają niszczenie progresywne elementu podczas ściskania, co wpływa na wartość pochłanianej energii. Przedstawiono różne rodzaje inicjatorów dla różnych kształtów elementów oraz określono, że elementy w postaci sfer, konstrukcji przekładkowej i stożków ściętych o kącie wierzchołkowym większym o 20° nie wymagają inicjatora niszczenia.

EN

The paper presents experimental results of the crush initiator influence on the energy absorption capability in the energy absorbing elements used in sandwich structure cores. It was proved in the carried out compression tests that crush initiators assure progressive crush, which impacts on the absorbed energy. Many kinds of initiators with different element shapes are investigated. It is found that spherical elements, sandwich structures and truncated cones with the vertex angle greater than 20° require no crush initiators.

4

Obtaining of petroleum resins using pyrolysis by-products 9. Petroleum resins with epoxy groups modified simultaneously with maleic anhydride and styrene

Bratychak M., Romasho I., Shyshchak O., Wacławek W.

Chemia i Inżynieria Ekologiczna

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2006

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Vol. 13, nr S1

25-33

EN

Petroleum resins modified simultaneously with maleic anhydride and styrene have been synthesized on the basis of C9 fraction, whieh is a by-product of ethylene production. The effect of temperature and process time on the yield and main characteristics of the resins has been studied with the following amounts of eomponents (mass %): C9 fraction - 70, styrene - 30, maleic anhydride - 1 and an initiator - 5. The structure of the product is con-firmed by chemical and IR-speetral methods. The conversion of unsaturated compounds presented in the C9 fraction during cooligomerization and material balance of the production process have been calculated. Hydrocarbon composition of strippants has been determined.

PL

Z frakcji C9, produktu odpadowego pirolizy oleju napędowego (dieslowego), otrzymano żywice petrochemiczne z grupami epoksydowymi, modyfikowane jednocześnie bezwodnikiem maleinowym i styrenem (PRESM). Badano wpływ temperatury i ilości bezwodnika maleinowego na wydajność reakcji i właściwości otrzymanych żywic; ich budowę badano za pomocą widm IR. Wyznaczono bilans materiałowy produkcji ww. żywic, jak również skład chemiczny nieprzereagowanej części surowca, tj. frakcji C9.

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The new initiators for free-radical polymerization of unsaturated polyester resins

Matynia T., Worzakowska-Żak M.

Polish Journal of Chemical Technology

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2004

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Vol. 6, nr 3

25-28

EN

The new free-radical initiators were prepared from the commercially available substrates: 60% hydrogen peroxide, ethyl methyl ketone, 1,2-propanodiol and high-molecular compounds containing hydroxylic groups such as hydroxypolyethers D 1002, D 2002, F3600T. 1,2-propanodiol and hydroxypolyethers were used as solvents of the hydroperoxide compounds. Such physical properties as density, viscosity, concentration of active oxygen and temperature of decomposition were determined for the synthesized initiators and Luperox using the differential scanning calorimeter. The unsaturated polyester resin Polimal 109 was used to determine the efficiency of the new initiatiors in the curing procedure at room temperature. The properties of the resin in the process of crosslinking and after curing were compared with the new initiators and the typical curing system containing ethyl methyl ketone hydroperoxide (Luperox) and cobalt (II) octoate.

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H2O2 as an initiator of free-radical polymerization

Gawdzik B., Matynia T., Worzakowska M.

Polish Journal of Chemical Technology

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2003

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Vol. 5, nr 3

103-105

EN

Synthesis and properties of new initiating systems formed from commercially available methyl ethyl ketone, hydroxypolyethers G 1000 and G 1002, and hydrogen peroxide (60%) are presented. Reaction was carried out in 1,2-propanodiol as a solvent. The obtained initiators with cobalt octoate as a promotor were applied for crosslinking of the commercially available unsaturated polyester resin. Properties of the resin were compared with those obtained while it was hardened by the typical curing system containing methyl ethyl ketone hydroperoxide (Luperox) and cobalt octoate.