Abstract: A method of forming simulated marble articles from materials polymerizable within a cell or mould characterized in that the mould is filled under conditions in which the polymerizable materials are introduced as streams following the flow path into the cell or mould and the contents are polymerized with the cell or mould disposed so that the flow lines are on a height gradient relative to each other. Limited intermixing of the compositions during the initial stages of the curing process produce an attractive simulated marble effect. The mould may be filled so that the flow lines are disposed in a near vertical position and then rotated so that they are in a near horizontal position with adjacent flow lines on a near vertical height gradient.

Abstract: A component of a polymerization catalyst is prepared by reacting an organomagnesium halide with a solid, inorganic oxide, then reacting the product with a Lewis Base compound, particularly an ester and finally with titanium tetrachloride. After reacting the organo-magnesium halide with the inorganic oxide it may be treated with a halogenating agent before it is reacted with the Lewis Base compound. The product obtained is combined with an organo-aluminium compound preferably together with a Lewis Base and used to polymerize an olefin monomer particularly propylene or mixtures of ethylene and a 1-olefine containing at least 4 carbon atoms. The catalyst system has a high activity, is stereospecific and has a lower proportion of halogen than some other catalyst systems.

Abstract: A component of a polymerization catalyst is prepared by reacting an organo-magnesium halide with a solid, inorganic oxide, then reacting the product with a Lewis Base compound, particularly an ester and finally with titanium tetrachloride. After reacting the organo-magnesium halide with the inorganic oxide it may be treated with a halogenating agent before it is reacted with the Lewis Base compound. The product obtained is combined with an organo-aluminium compound preferably together with a Lewis Base and used to polymerize an olefine monomer. The catalyst has a high activity, is stereospecific and has a lower proportion of halogen than some other catalyst systems.