Abstract: An expandable polystyrene composition in the form of beads is disclosed, comprising: (1) 100 parts by weight of a styrene polymer having in particular a weight-average molecular weight Mw ranging from 150 000 to 400 000 daltons, (2) from 3 to 20 parts by weight of a blowing agent, which is water or a mixture of water with at least one other blowing agent for example a hydrocarbon (3) from 0.1 to 12 parts by weight of at least one modified clay with an at least partially lipophilic nature. Also disclosed is a process for making the compositions.

Abstract: The present invention relates to a process for the synthesis of isocyanates and of isocyanate derivatives. Isocyanates are obtained by reacting an organic halide with a metal cyanate in an organic medium in the presence of a catalyst consisting of a complex of nickel with at least one organic ligand, in which complex the nickel is in the zero oxidation state.A carbamate or a urea, respectively, are obtained by a subsequent reaction with a hydroxy compound or a primary or secondary amine.Isocyanates and their derivatives are used especially either as refined synthesis agents for the production of pesticides and medications, or as monomers or comonomers for the preparation of many macromolecular compounds.

Abstract: The present invention relates to a process for the synthesis of isocyanates and of isocyanate derivatives. Isocyanates are obtained by reacting an organic halide with a metal cyanate in an organic medium in the presence of a catalyst consisting of a complex of nickel with at least one organic ligand, in which complex the nickel is in the zero oxidation state.A carbamate or a urea, respectively, are obtained by a subsequent reaction with a hydroxy compound or a primary or secondary amine.Isocyanates and their derivatives are used especially either as refined synthesis agents for the production of pesticides and medications, or as monomers or comonomers for the preparation of many macromolecular compounds.