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Wpływ nowego fotoinicjatora na przebieg reakcji fotochemicznych w poli(chlorku winylu)

Kaczmarek H., Gałka P., Wrzyszczyński A., Olszewski K., Janota H.

Polimery

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2009

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T. 54, nr 3

202-208

PL

Przedstawiono dwuetapową syntezę nowego fotoinicjatora degradacji polimerów, mianowicie 4-metoksybenzoesanu S-4-benzoilofenylu, którego użyto do modyfikacji fizycznej poli(chlorku winylu) (PVC). Przebieg procesów fotochemicznych przebiegających w tym modyfikatorze oraz w cienkich błonach samego PVC i PVC z 2-proc. zawartością inicjatora badano metodami spektroskopii absorpcyjnej (UV-Vis i FT-IR). Stwierdzono przyspieszające działanie dodanego związku w procesie dehydrochlorowania i utleniania PVC pod wpływem promieniowania UV o długości fali ?=254nm. Zaproponowano mechanizm reakcji fotochemicznych zainicjowanych w PVC przez omawiany fotoinicjator.

EN

A two-stage synthesis of new photoinitiator of polymer degradation, namely S-(4-benzoylphenyl)-4-methoxythiobenzoate, is presented [equation (1) and (2)]. The initiator was used for physical modification of poly(vinyl chloride) (PVC). The courses of photochemical processes going in thin films made of PVC itself or with addition of 2% of initiator were investigated by absorption spectroscopy (UV-Vis and FTIR, Fig. 1-7). It has been found that the initiator accelerated the processes of dehydrochlorination and oxidation of PVC under the influence of UV radiation of wavelength ?=254nm. The mechanism of photochemical reactions initiated in PVC by the initiator discussed was proposed.

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Stability of 1-Phenacylpyridinium and 1-(2-Hydroxy-2-phenylvinyl)pyridinium Cations

Ośmiałowski B., Janota H., Gawinecki R.

Polish Journal of Chemistry

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2003

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Vol. 77 / nr 2

169-177

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1H, 13C and 15N NMR Spectral and X-ray Structural Studies of 2-Arylsulfonylamino-5-chlorobenzophenones

Kolehmainen E., Nissinen M., Janota H., Gawinecki R., Ośmiałowski B.

Polish Journal of Chemistry

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2003

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Vol. 77 / nr 7

889-894

EN

Six 2-(4-R-phenylsulfonylamino)-5-chlorobenzophenones were prepared and their 1H, 13Cand 15NNMRspectra recorded and assigned. The dependence between the chemical shift of the amide proton and Hammett _ substituent constants is of the V type. Substituent effect on the chemical shift of the amide nitrogen atom was found insignificant. X-ray analysis shows that the terminal benzene rings in 2-(4-nitrophenylsulfonylamino)-5-chlorobenzophenone are located close to each other. They are not, however, parallel, dihedral angle between them being equal to 10.86 deg (MP2/6-31G**//HF/6-31G** ab initio calculations show this to be 20.44 deg). This shows that the mutual orientation of two benzene rings in the molecule of this compound is caused by the _-_ stacking. It is additionally reinforced by the intramolecular NH…O=C hydrogen bond. Except the dihedral angle between the benzene rings, X-ray determined structure of 2-(4-nitrophenylsulfonylamino)-5-chlorobenzophenone is very similar to this optimized by the ab initio calculations.