Synergistic agent

N-Nitroso-N-cyclohexylhydroxylamine is a synergistic agent for insecticides [94] it increases the insecticidal activity ofchlordane. Certain N-alkylphenylnitrosamines [95] and alkyl N-alkyl-N-nitrosocarbamates [96] are insecticides and fungicides, and may also be used for the impregnation of fabrics, etc. They have larvicidal action against Drosophila melanogaster and can also kill all moth larvae and weevils. 

Most of the studies carried out on cesium extraction conclude that the most efficient crown ethers for extraction of this cation are benzo-21-crown-7 derivatives. Like dicarbollides, these compounds need a synergistic agent or polar diluent modifier to allow cesium to be extracted from very acidic solutions. The resulting selectivity for cesium over sodium is low. Only dialkoxy-calix[4]arene-crown-6 and calix[4]arene bis(crown-6) compounds allow objectives to be fulfilled extraction of cesium at low-level concentration from acidic media.19... 

Bourbigot, S., Le Bras, M., Delobel, R., Breant, P., and Tremillon, J.-M. 1996. 4A Zeolite synergistic agent in new flame retardant intumescent formulations of polyethylenic polymers—Study of the constituent monomers. Polym. Deg. Stab. 54 275-283. 

It has been shown that the required loading levels of metal hydroxides to flame retard polyolefins can be reduced by the addition of transition metal oxides as synergistic agents. For example, a combination of 47.6% MH modified with nickel oxide in PP gave a UL94 V-0 flammability rating, which would require -55% of unmodified MH.4 These systems, however, can only be used where the color of the product is not important. 

Le Bras, M. and Bourbigot, S. 1998. Fire retarded intumescent thermoplastics formulations, synergy and synergistic agents-a review. In Fire Retardancy of Polymers—The Use of Intumescence, Le Bras, M., Camino, G., Bourbigot, S., and Delobel, R. (Eds.), Cambridge, London The Royal Society of Chemistry, pp. 64—75. 

Z.L. Ma, W.Y. Zhang, and X.Y. Liu, Using PA6 as a charring agent in intumescent polypropylene formulations based on carboxylated polypropylene compatibilizer and nano-montmorillonite synergistic agent, J. Appl. Polym. Sci., 2006, 101 739-746. 

Bourbigot, S. Le Bras, M. Breant, P. et al. Zeolites New synergistic agents for intumescent fire retardant thermoplastic formulations—criteria for the choice of the zeolite. Fire Mater. 1996, 20, 145-154. 

Ramakumar, J., Nayak, S.K., and Maiti, B., Transport of uranyl ion across a bulk liquid membrane using calixarene and synergistic agents as carriers. J. Membr. Sci., 2002, 196 203-210. 

Dithizone (in the presence of pyridine or phen as synergistic agents) forms an extractable (CCI4) complex with manganese (e = 5.7-10 at 510 nm) [39 2]. Manganese can also be determined with HTTA (e = 6.1-10 at 420 nm) [43,44] and 8-hydroxyquinoline (extraction in the presence of quaternary bases) [45]. 

As a matter of fact, various tetraalkylammonium salts, the most famous one being the commercial Aliquat 336 (a 2 1 mixture of methyl trioctyl and methyl tridecylammonium chloride), are used as synergistic agents for Ln (III) extraction in traditional solvents (Atanassova, 2009 Atanassova and Dukov, 2010), and we would like to recall that many tetraalkylammonium salts are, in fact, ILs for example, tetraoctylammonium bromide melts at ca. 95 °C. On the other hand, new routes for the synthesis of ammonium-type ILs have been proposed (Mikkola et al., 2006 Sun et al., 1998). However, it is out of the scope of this work to review all literature involving Aliquat salts, especially because, being commercial mixtures, their chemical and physical properties are difficult to determine. Therefore, we will restrict ourselves to systems in which the additive was clearly considered by the authors as an IL. 

Synergistic agents may be added to the three additive components. They may play different parts they increase the amount of stable carbon formed (dextrine derivatives), increase the amount of stable high temperature acidic species (clays, zeolite or functionalized co-polymers) or increase the number of polymer chains trapped in the intumescent shield (aluminosilicates). 

Acidic agent Carbonization agent Spumific Synergistic agent LOI volume (%) WI--94 rhr (kW/m ) ... 

Shamsipur, M., Davarkhah, R. Khanchi, A.R. (2010) Facilitated transport of uranium(Vl) across a bulk liquid membrane containing thenoy Itrifluoroacetone in the presence of crown ethers as synergistic agents. Separation and Purification Technology, 71 (1), 63-69. 

Le Bras, M. Bourbigot, S. Fire retarded intumescent thermoplastic formnlations, synergy and synergistic agents review, in M. Le Bras, G. Camino, S. Bonrbigot, and R. Delobel, Eds., Fire Retardancy of Polymers The Use of Intumescence. Royal Society of Chemistry, London, 1998, pp. 64-75. 

---