Abstract: The present invention provides a continuous process for the epoxidation of an olefinic compound with an oxidant, which process comprises reaction of an olefinic compound with an oxidant in the presence of a catalyst in an apparatus that comprises a reactive distillation column, which column comprises (i) a reactive section, which comprises the catalyst (ii) a rectifying section situated above the reactive section and adapted to allow separation of reagents and/or by-products from products (vii) a stripping section situated below the reactive section and adapted to allow separation of product from reagents and/or by-products (viii) a vessel situated below the stripping section and adapted to provide a source of heat for the column and in which initial vaporization of one or more of the reagents can occur, wherein the temperature in the reactive section (i) is a temperature at which the reaction between the olefinic compound and the oxidant takes place and the temperature in the stripping section (iii) is hi

Abstract: The present invention provides a continuous process for the epoxidation of an olefinic compound with an oxidant, which process comprises reaction of an olefinic compound with an oxidant in the presence of a catalyst in an apparatus that comprises a reactive distillation column, which column comprises (i) a reactive section, which comprises the catalyst (ii) a rectifying section situated above the reactive section and adapted to allow separation of reagents and/or by-products from products (vii) a stripping section situated below the reactive section and adapted to allow separation of product from reagents and/or by-products (viii) a vessel situated below the stripping section and adapted to provide a source of heat for the column and in which initial vaporisation of one or more of the reagents can occur, wherein the temperature in the reactive section (i) is a temperature at which the reaction between the olefinic compound and the oxidant takes place and the temperature in the stripping section (iii)

Abstract: The present invention provides a continuous process for the epoxidation of an olefinic compound with an oxidant, which process comprises reaction of an olefinic compound with an oxidant in the presence of a catalyst in an apparatus that comprises a reactive distillation column, which column comprises (i) a reactive section, which comprises the catalyst (ii) a rectifying section situated above the reactive section and adapted to allow separation of reagents and/or by-products from products (ix) a stripping section situated below the reactive section and adapted to allow separation of product from reagents and/or by-products (x) a vessel situated below the stripping section and adapted to provide a source of heat for the column and in which initial vaporization of one or more of the reagents can occur, wherein the temperature in the reactive section (i) is a temperature at which the reaction between the olefinic compound and the oxidant takes place and the temperature in the stripping section (iii) is higher

Abstract: The present invention provides a continuous process for the epoxidation of an olefinic compound with an oxidant, which process comprises reaction of an olefinic compound with an oxidant in the presence of a catalyst in an apparatus that comprises a reactive distillation column, which column comprises (i) a reactive section, which comprises the catalyst (ii) a rectifying section situated above the reactive section and adapted to allow separation of reagents and/or by-products from products (ix) a stripping section situated below the reactive section and adapted to allow separation of product from reagents and/or by-products (x) a vessel situated below the stripping section and adapted to provide a source of heat for the column and in which initial vaporisation of one or more of the reagents can occur, wherein the temperature in the reactive section (i) is a temperature at which the reaction between the olefinic compound and the oxidant takes place and the temperature in the stripping section (iii) is higher

Abstract: The present invention relates to a method of preparing a separation medium starting with an aqueous solution of spherical and preferably functionalised primary particles of defined size, comprising the following steps: a) inverse suspension dispersing said aqueous solution of primary particles as droplets in oil; b) evaporation to remove said aqueous solution and fusion between particles to form spherical aggregates; c) size fractionation of aggregates from step b); and optionally d) repeating steps a) to c) an optional number of times to form progressively larger spherical aggregates. The invention also relates to a separation medium produced by this method. The present separation medium can be used in chromatography in the form of essentially spherical aggregates in packed or expanded bed columns or in the form of assembled aggregates on a support for filtration purposes.

Abstract: The present invention relates to a heterogeneous polyimide-supported transition metal complex catalyst for epoxidation of olefin, which is prepared by impregnating a heat- and acid-resistant polyimide resin with a homogeneous metal catalyst of molybdenum, vanadium, tungsten or titanium, and a process for preparing epoxy compounds using the same. The heterogeneous polyimide-supported transition metal complex catalyst of the invention provides superior catalytic activity, selectivity and stability in the epoxidation of higher olefin. Further, the catalyst of the invention has strong resistance against heat and acid. Besides, the catalyst of the invention may provide the following advantages which are critical in industrial use: it permits relatively high yield of epoxy compounds; and, it can be easily separated from the reaction product, which eases recycling of the catalyst.

Abstract: A catalyst composition having high epoxidation activity and resistant to leaching of its metal comprises molybdenum, vanadium, tungsten and/or titanium complexed to an organic or inorganic support through the intermediacy of an imidazole ligand. The catalyst may be used in epoxidation of olefinic compounds.

Abstract: A substrate comprises a porous polymeric material having a porosity of at least 75% and comprising pores having a diameter within the range 1 to 100 .mu.m and being interconnected by a plurality of holes, and a gel or material adapted in use to form a gel which gel or pre-gel materials is contained and retained within the pores of the polymeric material and is adapted in use to interact with a reactive species and can be made by depositing and retaining the gel or a material adapted in use to form the gel within the pores of the porous polymeric material. The high porosity of the porous polymeric material in combination with the retention of the gel within the pores permit high loading capacities, particularly in the area of peptide synthesis to be achieved. The substrate can be employed in chemical synthesis, chromatography techniques, ion exchange and separation techniques.

Abstract: A porous polymeric material has cell sizes within the range 100 to 0.5 .mu.m and total pore volume with respect to the overall volume of the material in the range 75 to 98% and includes cross-linked polycondensation polymeric material. The material can be made from a high internal phase emulsion in which the cross-linked polycondensation polymer is formed in the continuous phase. The materials are preferably open interconnected cellular structures. They can be made of a wide range of polycondensation materials. The materials are thus highly porous and light weight and have a range of properties depending primarily on their constituent polycondensation materials.

Abstract: A porous polymeric material has cell sizes within the range 100 to 0.5 .mu.m and total pore volume with respect to the overall volume of the material in the range 75 to 98% and includes cross-linked polycondensation polymeric material. The material can be made from a high internal phase emulsion in which the cross-linked polycondensation polymer is formed in the continuous phase. The materials are preferably open interconnected cellular structures. They can be made of a wide range of polycondensation materials. The materials are thus highly porous and light weight and have a range of properties depending primarily on their constituent polycondensation materials.

Abstract: A substrate comprises a porous polymeric material having a porosity of at least 75% and comprising pores having a diameter within the range 1 to 100 .mu.m and being interconnected by a plurality of holes, and a gel or material adapted in use to form a gel which gel or pre-gel materials is contained and retained within the pores of the polymeric material and is adapted in use to interact with a reactive species and can be made by depositing and retaining the gel or a material adapted in use to form the gel within the pores of the porous polymeric material. The high porosity of the porous polymeric material in combination with the retention of the gel within the pores permit high loading capacities, particularly in the area of peptide synthesis to be achieved. The substrate can be employed in chemical synthesis, chromatography techniques, ion exchange and separation techniques.

Abstract: Polymeric materials useful as positive resists comprise a backbone formed from an addition polymer which is degradable by radiation and at least 3 pendant polymeric groups which show no appreciable positive resist characteristics. Preferably these materials comprise a backbone which is a polymethacrylate ester and from 3 to 5 pendant polystyrene groups. These polymers exhibit increased sensitivity and resistance to plasma processing and provide resists which are useful as components of integrated circuits.