Abstract: A fire retardant, impact resistant polyamide composition containing 1 to 25% of a rubbery copolymer containing functional groups derived from maleic, fumaric, norbornadiene and succinic anhydrides or an alicyclic carboxylic acid or functional derivative thereof having a cis-form double bond in the ring, 10 to 30% of a halogenated polymer having a weight average molecular weight greater than 5,000 and a synergist for the halogenated fire retardant. The composition provides a good level of impact strength in combination with a high level of fire retardancy. A particularly good balance of properties can be obtained from compositions containing fillers, especially glass fibres.

Abstract: A fire retardant polyamide composition comprising at least 35% by weight of polyamide having a molecular weight of at least 3000, at least 3.5% but preferably not more than 10% by weight of the condensation product of 2 moles perchlorocyclopentadiene and 1 mole of 1,5-cyclooctadiene, at least 2%, preferably at least 4% desirably not more than 10% by weight of melamine, a salt of melamine or an organic derivative of melamine and at least 0.5%, but preferably not more than 5.0% of at least one oxide selected from iron oxide and tin oxide, wherein the weight ratio of chlorinated compound to oxide is between 1:1 and 10:1 preferably between 2:1 and 6:1 and the constituents of the composition total 100%. The composition provides improved burning performance in the UL94 test in that dripping is prevented. The composition also provides acceptable burning performance at a lower concentration of total additives than when halogenated fire retardant/synergistic oxide combinations are used.

Abstract: A glass-reinforced, fire-retardant, arc-track resistant polyamide composition characterized in that it contains:(a) at least 35% by weight of a fibre-forming polyamide,(b) 15% to 30% by weight of glass fibres or particulate fillers,(c) 17.5 to 27.5% by weight of melamine or melamine cyanurate,(d) 1 to 10% by weight of brominated fire retardants selected from a brominated polyphenylene oxide or a brominated epoxy resin, and(e) a synergist selected from zinc oxide, zinc borate, a mixture of zinc oxide and zinc borate and a mixture of antimony oxide and zinc borate, wherein the concentration of oxide present in the synergist is between 0 and 5%, the concentration of borate present is between 0 and 25% by weight, and the total weight of synergist is at least 1%, the weight percentages of the constituents (a), (b), (c), (d) and (e) totalling 100%.

Abstract: A reinforced, fire retardant, polyamide composition containing(a) at least 35% by weight of a fibre-forming polyamide,(b) 15 to 30%, by weight of glass fibres or particulate fillers,(c) 15 to 30%, by weight of melamine demi-sulphate,(d) at least 2.5%, by weight of a halogenated compound selected from the condensation product of 2 moles chlorocylopentadiene and 1 mole of 1,5-cyclooctadiene, brominated polystyrene, brominated polyphenylene oxide or a brominated epoxy resin, and(e) a synergist selected from at least one of zinc borate, zinc oxide and mixtures of antimony oxide and zinc borate, wherein the concentration of oxide present is between 0 and 5%, the concentration of zinc borate is between 0 and 25%, preferably between 2 and 15% by weight and the total weight of synergist is at least 1% by weight and wherein the weight percentages of the constituents total 100%.

Abstract: A glass-reinforced, fire-retardant, arc-track resistant composition characterized in that it contains:(a) at least 35% by weight of a fibre-forming polyamide,(b) 15 to 25% by weight of glass fibres,(c) 16-30% by weight of melamine cyanurate,(d) 2 to 7% by weight of the condensation product of 2 moles of chlorocyclopentadiene and 1 mole of 1,5-cyclooctadiene, and an amount of(e) a fire retardant synergist selected from antimony oxide, iron oxide and stannic oxide,to give a weight ratio of (d) to (e) between 1:1 and 5:1, and wherein the constituents of the composition total 100%.

Abstract: A solid compound of a transition metal is ground in the presence of aluminium chloride, titanium tetrachloride and at least one organo-Lewis Base compound. The transition metal compound is typically titanium trichloride. The Lewis Base compound is an organo-phosphorus compound, preferably one which also contains nitrogen, such as 2-dimethylamino-1,3-dimethyl-1,3,2-diazaphospholidine-2-oxide or an organo-sulphur compound such as diphenyl sulphone. The solid compound of the transition metal may include aluminium chloride and if the amount of this aluminium chloride is at least 50% molar, there is no need to make a separate addition of aluminium chloride to the mixture which is ground. The ground product can be used as a component of an olefine polymerization catalyst.

Abstract: A solid compound of a transition metal is ground in the presence of aluminum chloride; titanium tetrachloride and at least one specified organic sulphur-containing compound are added, the whole mixture is ground and the ground product is then washed with an aromatic liquid. The transition metal compound is typically titanium trichloride. The organic sulphur-containing compound can be a sulphone, a sulphonamide or a condensed ring system containing at least one heterocyclic sulphur atom. The organic sulphur-containing compound can be diphenylsulphone. The solid compound of the transition metal may be one which also includes aluminum chloride. The quantities of materials added to the transition metal compound are, for each mole of the transition metal compound, 0.10 up to 2.50 moles of the organic sulphur-containing compound, 0.01 up to 0.50 mole of titanium tetrachloride and 0.01 up to 2.50 moles of aluminum chloride.

Abstract: A titanium trihalide is ground with an organic Lewis Base compound which contains at least one phosphorus atom, and optionally at least one nitrogen atom, and a titanium tetrahalide, the Lewis Base and the titanium tetrahalide being used in amounts of 5 to 75, preferably 5 to 50%, molar and 1 to 50, preferably 5 to 30% molar respectively relative to the titanium trihalide. The materials are conveniently milled together and the milled product can be used as a component of an olefine polymerization catalyst and when such catalysts are used to polymerize propylene a high activity is achieved together with satisfactory stereospecificity.

Abstract: A solid compound of a transition metal is ground in the presence of aluminium chloride; titanium tetrachloride and at least one specified organic sulphur-containing compound are added, the whole mixture is ground and the ground product is then washed with an aromatic liquid. The transition metal compound is typically titanium trichloride. The organic sulphur-containing compound can be a sulphone, a sulphonamide or a condensed ring system containing at least one heterocyclic sulphur atom. The organic sulphur-containing compound can be diphenylsulphone. The solid compound of the transition metal may be one which also includes aluminium chloride. The quantities of materials added to the transition metal compound are, for each mole of the transition metal compound, 0.10 up to 2.50 moles of the organic sulphur-containing compound, 0.01 up to 0.50 mole of titanium tetrachloride and 0.01 up to 2.50 moles of aluminium chloride.