The use of polymer flame retardants has an important role in saving lives. The main flame retardant systems for polymers currently in use are based on halogenated, phosphorous, nitrogen, and inorganic compounds. All of these flame retardant systems basically inhibit or even suppress the combustion process by chemical or physical action in the gas or condensed phase. Conventional flame retardants, such as halogenated, phosphorous, or metallic additives, have a number of negative attributes. An ecological issue of the application of conventional flame retardants demands the search of new polymer flame retardant systems. Among the new trends of flame retardancy are intu-mescent systems, polymer nanocomposites, preceramic additives, low-melting glasses, different types of char formers, and polymer morphology modification processing. The brief explanations on the three major types of flame retardant systems (intumescent systems, polymer nanocomposites, and polymer organic char formers) are the subject of this overview.

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Stochastic programming is a typical method for addressing the uncertainties in capacity expansion planning problem. However, the corresponding deterministic equivalent model is often intractable with considerable number of uncertainty scenarios especially for stochastic integer programming (SIP) based formulations. In this article, a hybrid solution framework consisting of augmented Lagrangian optimization and scenario decomposition algorithm is proposed to solve the SIP problem. The method divides the solution procedure into two phases, where traditional linearization based decomposition strategy and global optimization technique are applied to solve the relaxation problem successively. Using the proposed solution framework, a feasible solution of the original problem can be obtained after the first solution phase whereas the optimal solution is obtained after the second solution phase. The effectiveness of the proposed strategy is verified through a numerical example of two stage stochastic integer program and the capacity expansion planning examples. © 2011 American Institute of Chemical Engineers AIChE J, 2012

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On the basis of mixes of phenolformaldehide and epoxy resins at the presence of some silicon organic compounds and fiber glasses annealed in vacuum and hydrogen media the new conductive monolithic materials have been created. Conductive, magnetic and some other properties of these materials were investigated. It was established experimentally that the obtained products are characterized by semiconductive properties, the level of conductivity and conductive type of which are regulated by selection of technological methods. The density and mobility of carriers increase at increasing of annealing temperature up to definite levels. The temperature dependence of the electrical conductivity and charge mobility were described by Mott formulas. The magnetic properties of the annealed materials were investigated by ESR method. It was established that at annealing free radicals and other paramagnetic centers are formed. On the basis of the obtained results it was proposed that formation of conducting clusters and the charge transport between them is provided by mechanism of charge jumping with alternative longevity of the jump.