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Novel trisubstituted ethylenes, ring-disubstituted propyl 2-cyano-3-phenyl-2-propenoates, RPhCH˭C(CN)CO2C3H7 (where R is 2-fluoro-5-methoxy, 2-fluoro-6-methoxy, 3-fluoro-4-methoxy, 4-fluoro-3-methoxy, 5-fluoro-2-methoxy, 2-fluoro-6-methyl, 3-fluoro-2-methyl, 4-fluoro-2-methyl, 4-fluoro-3-methyl, 5-fluoro-2-methyl) were prepared and copolymerized with styrene. The monomers were synthesized by the piperidine catalyzed Knoevenagel condensation of ring-substituted benzaldehydes and propyl cyanoacetate and characterized by CHN elemental analysis, IR, 1H- and 13C-NMR. All the ethylenes were copolymerized with styrene (M1) in solution with radical initiation (ABCN) at 70°C. The composition of the copolymers was calculated from nitrogen analysis, and the structures were analyzed by IR, 1H and 13C-NMR, GPC, DSC, and TGA. Decomposition of the copolymers in nitrogen occurred in two steps, first in the 200–500°C range with residue (1.4–3.0% wt.), which then decomposed in the 500–800°C range.

This report describes the results obtained by application of three methods (i.e., visual iodate, potentiometric bromate, and colorimetric molybdenum blue) to the determination of hydrazine and its methyl derivatives. In addition, the validity of continuous sampling techniques for vapor concentrations in air was determined by estimating the stability of acidified aqueous solutions of the hydrazines toward prolonged aeration.