We have studied the influence of nitrogen on the chemical properties of the hydrogenated carbon nitride (a-CN(x):H) film deposited by CH(4)/N(2) dielectric barrier discharge (DBD) plasma. X-ray photoelectron spectroscopy (XPS) indicates that carbon and nitrogen form an unpolarized covalent bond in these C-N(x) materials, and the observed chemical shift in the C 1s and N 1s binding energy is explained with respect to N 1s incorporation. Furthermore, the average nitrogen content (N/C approximately 0.76) in the films was systematically varied by changing the nitrogen partial pressure (CH(4)/N(2) approximately from 5:1 to 1:7) which is well supported by the elemental analysis. Fourier transform infrared (FTIR) absorption spectra exhibit significant changes in different C-N, C identical withN, and NH/OH molecular bands at higher nitrogen concentration in the film. The isonitrile and nitrile groups (-NC and -CN) are increased with the increase of deposition time. In addition, the elemental analysis, proton NMR, and thermolysis mass spectrum show that the composition of the film with the ratio CH(4)/N(2) approximately 1:1 is C, 67.68; H, 9.88; N, 16.53 (in wt %) and that the film is composed of polymers, probably containing linear chains which are cleaved off on heating in vacuum.

The 2-phosphinophenolate nickel catalyzed oligo- or polymerization of ethylene in the presence of olefins usually leads to improved conversion or copolymerization. The outcome depends strongly on the nature of the P-substituents and olefins. The diphenylphosphinophenolate ligand (PPHH) favors improved yields of waxy linear ethylene oligomers, whereas the more P-basic dicyclohexylphosphinophenolate (CCHH) induces incorporation of alkyl-, aryl-, and ester-substituted α-olefins into a growing ethylene polymer chain and larger molar masses of the polymers. Depending on the nature of the olefin, the reaction rate and the conversion are lowered by olefin incorporation. Ester groups are tolerated if distant to the CC bond but block the catalyst if close to the olefinic group. A remarkable increase of activity accompanied by small branching was observed in the copolymerization with ethyl undecenoate by the nickel diphenylphosphinophenolate catalyst. 13C and 1H NMR spectra give evidence that ethylene copolymers with isolated side groups, imbedded into linear polyethylene blocks with vinyl end groups, are formed.

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