It was demonstrated by infrared spectroscopic results that polyethylene can be oxidized a t low-temperatures under the influence of the gas discharge orland inorganic oxidizing agents. The extent of oxidation depends on the reaction temperature, the oxidation agent, and the structure of the polyethylene. The reaction is slower at lower density of branching and a t higher degree of crystallinity. By formation of polar groups, the free surface energy and consequently, the adhesion strength is considerably increased. According t o the experimental results many possible reactions are presented for the oxidation of polyethylene. Zur Oxidation uon PolyethyZen Lei niedrigen TemperaturenDurch infrarotspektroskopische Messungen wird gezeigt, daB Polyethylen bei niedrigen Temperaturen unter Einwirkung von Gasentladungen und/oder anorganischen Oxidationsmitteln oxidiert werden kann. Das AusmaD der Oxidation hangt von der Reaktionstemperatur, dem Oxidationsmittel und der Struktur des Polyethylens ab. Die Oxidation verlauft langsamer bei kleinerem Verzweigungsgrad und gr6Berer Kristallinitat. Durch die Bildung polarer Gruppen nehmen die freie Oberflachenenergie und infolgedessen die Adhasionsfestigkeit betrachtlich zu. Auf Grund der experimentellen Ergebnisse werden eine Reihe moglicher Reaktionen fur die Oxidation des Polyethylens vorgeschlagen. IE eonpoy oxuc.wnwt nonwmunena npu HUBIEUX me.mepamypax IIOA ~o s~e i c~s u e~ r a a o~~x p a a p s~o~ u/um HeopraHmecmx oKm.naTexe8. OKwcrenHe ~~B H C E I T OT TeMnepaTypu p e a q m , OKncnuTem u C T~Y K T Y~M nomaTmeHa. Omcneme IIPOHCXOAHT MeAJrenHee npu Memmei cTenenH pas-HK-CneKTpOCKOnuYeCKElMEl H3MepeHHRMU IIOKa3aH0,qTO IIOnW3TWJIeH MOXeT OKHCJIRTbCH IlpH HHBKMX TeMIIepaTypaX BeTBJIeIiHR EI 60nbmei KpHCTaJIJIHYHOCTJI. BCieACTBHe 0 6 p a s o a a~~~ IIOJIRPHMX FpylIII 3Ha9EITeJIbHO YBeJIE' XHBaIOTCR CBO6OAHtlf3 IIOBepXHOCTHaR 3HeprHR EI CJIeAOBaTeJIbHO aXre3HOHHacI UpOqHOCTb. Ha OCHOBe 3KCIIepMMeHTaJIbHMXp e a y n b~a~o~ npeanonomen I)RA BO~MOXHMX p e a q a i i ~J I K o m c n e n m nomaminena.

SynopsisKinetics of the uptake of polypropylene by the cellulose were studied. According to the experimental results, the reaction begins with an induction period which cannot be explained on the basis of the reaction mechanism of Ziegler-Natta catalysts. Most probable reason of this period may be the initial unsaturation of the system.Studies on the effect of concentration of the catalyst (TiCL) showed that, above the order of magnitude of 10-2 mole/l, uptake of polypropylene by the cellulose is directly proportional to the concentration of Tic,. The maximum catalytic activity was observed at the molar ratio of ALEta to TiCL equal to 1.5.Concentration of propylene supported by the cellulose can be increased by elevation of the temperature.By increasing the concentration or the specific surface area of the cellulose a t a constant concentration of the cellulose a t a constant concentration of the catalyst, a kind of saturation appears on the cellulose fibers with respect to the adsorption of the metal chloride. Thus, increasing the specific surface area does not involve an increase in the uptake of polypropylene, in fact, increasing the concentration of the cellulose results in a drop in the amount of propylene to be taken up.On the basis of the infrared spectroscopical and the X-ray diffraction results, no differences were found between the mechanical mixture of the components and the cellulose fibers coated with polypropylene.Mechanical strength of paper sheets was poor compared with that of sheets from pure cellulose. Cellulose encapsulated with polypropylene can be used in the paper industry as an interlayer in laminated papers.

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SYNOPSISIt was found that an equimolar complex is formed from acrylonitrile with triethylaluminum. The complex formation was verified by infrared spectroscopy. The original bands of acrylonitrile at 2235 cm-I shifted and the new bands appeared at 2225 and 2275 cm-l. Copolymerization of acrylonitrile with propylene was proved to be possible with a Tick-AIEt3 catalyst system.Kinetic studies on copolymerization of propylene with acrylonitrile showed that composition of the starting monomer mixture markedly influenced the course of the reaction and the acrylonitrile content of the copolymer.Optimum conditions of the copolymerization reaction were as follows: temperature, 7 0 T ; reaction time, 30 min; molar ratios of acrylonitrile to the metal alkyl and Al to Ti, 1 :1 and 2;1, respectively, concentration of the total amount of monomers. Conversion is influenced by the aging time of the acrylonitrile-metal alkyl complex; the yield is a linear function of the aging time. Composition of copolymers was determined by chemical analysis. 497

This work is devoted to the infrared study of the products of the copolymerization of propylene and vinyl chloride with the modified TiCl3–Et3Al catalyst. Thus, in our view the data given demonstrates two important features of the copolymerization process of propylene and vinyl chloride on the modified Ziegler‐Natta catalyst: 1. that real copolymerization takes place in the case of this monomer pair; and 2. that copolymerization procedes on the stereospecific active sites of the heterogeneous catalyst, i.e., on the same sites which are responsible for the stereoregular polymerization of olefines. Infrared study allows one to estimate the distribution of the propylene units in the copolymers. The distribution is very typical of the random copolymers obtained with the stereospecific catalysts.