Formation of chlorinated hydrocarbons and polycyclic aromatic hydrocarbons (PAHs) were determined using a laboratory-scale incinerator when combusting materials at different temperatures, different concentrations of hydrochloric acid (HCl), and when combusting various types of polymers/newspaper. Polychlorobenzenes (PCBz), polychlorophenols (PCPhs), polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs) and their toxic equivalency (TEQ) and PAHs were highlighted and reported. Our results imply maximum formation of chlorinated hydrocarbons at 400 degrees C in the following order; PCBz>or=PCPhs>>PCDFs>PCDDs>TEQ on a parts-per-billion level. Similarly, a maximum concentration of chlorinated hydrocarbons was noticed with an HCl concentration at 1000 ppm with the presence of paraffin powder in the following order; PAHs>PCBz>or=PCPhs>>PCDFs>PCDDs>TEQ an a parts-per-billion level. PAHs were not measured at different temperatures. Elevated PAHs were noticed with different HCl concentrations and paraffin powder combustion (range: 27-32 microg/g). While, different polymers and newspaper combusted, nylon and acrylonitrile butadiene styrene (ABS) produced the maximum hydrogen cyanide (HCN) concentration, concentrations of PCDD/FS, dioxin-like polychlorinated biphenyls (DL-PCBs), and TEQ were in a decreasing order: polyvinylchloride (PVC)
ABSTRACT:Anionic copolymerizations of trans-stilbene (M2) with butadiene (M1), isoprene (M1), and 2,3-dimethylbutadiene (M1) were studied in tetrahydrofuran (THF) at 0°C and in benzene at 40°C by means of n-butyllithium (n-BuLi) as an initiator. All the copolymerizations in THF gave alternating copolymers, and the rate of the consumption of M1 decreased as follows: butadiene > isoprene > 2,3-dimethylbutadiene. The co polymerizations with isoprene and 2,3-dimethylbutadiene in THF spontaneously stopped, and the unchanged M1 monomers remained when the concentration of n-BuLi was low, where the final yields were lower in the copolymerization with 2,3-dimethylbutadiene with the same concentration of n-BuLi. The final yields increased with an increase in n-BuLi and decreased with increasing [M2]0/[Mi]o ratio. The copolymerization with butadiene was completed without the remaining M1 monomer. In all cases the electronic spectra of the reaction mixtures in THF showed no peak near 540 mµ in the initial stage of the reactions, but a new peak appeared near 540 mµ in time. The order of the optical densities of the peak after a prolonged time was 2,3-dimethylbutadiene > isoprene > butadiene. The microstructures of the dienes in the homopolymers and alternating copolymers which were polymerized in THF were determined by NMR spectroscopy. The alternating copolymers had more 1,4-structure than the corresponding homopolymers, and the 1,4-content in the formers decreased in the following order: 2,3-dimethylbutadiene > isoprene > butadiene. The dienes, however, were completely consumed in the copolymerizations in benzene. In the copolymerizations with butadiene and isoprene, little transstilbene was incorporated into the copolymers, but a considerable amount of trans-stilbene was copolymerized with 2,3-dimethylbutadiene.
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